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diff --git a/doc/manuals/Makefile b/doc/manuals/Makefile new file mode 100644 index 00000000..092856d8 --- /dev/null +++ b/doc/manuals/Makefile @@ -0,0 +1,14 @@ +TOPDIR := .. +ASCIIDOCS := osmobts-usermanual osmobts-abis + +include $(TOPDIR)/build/Makefile.asciidoc.inc + +# for the upload target +include $(TOPDIR)/build/Makefile.inc + +# dependencies +osmobts-abis.pdf: abis/*.adoc abis/*.msc +osmobts-usermanual.pdf: chapters/*.adoc + +clean: + rm -rf $(cleanfiles) diff --git a/doc/manuals/abis/abis-startup.msc b/doc/manuals/abis/abis-startup.msc new file mode 100644 index 00000000..d30fe41d --- /dev/null +++ b/doc/manuals/abis/abis-startup.msc @@ -0,0 +1,23 @@ +msc { + bts [label="BTS"], bsc [label="BSC"]; + + bts => bsc [label="TCP Connect (Port 3002, OML)"]; + bts box bsc [label="IPA CCM Identification (Port 3002)"]; + bts <= bsc [label="OML Configuration of BTS via OML"]; + ...; + bts <= bsc [label="OML (TRX=0) IPA RSL CONNECT"]; + bts => bsc [label="TCP Connect (Port 3003, RSL, TRX 0)"]; + bts box bsc [label="IPA CCM Identification Port 3003"]; + bts <= bsc [label="RSL BCCH filling (System Information)"]; + bts <= bsc [label="RSL SACCH filling (SI 5/6)"]; + ...; + bts <= bsc [label="OML (TRX=1) IPA RSL CONNECT"]; + bts => bsc [label="TCP Connect (Port 3003, RSL, TRX 1)"]; + bts box bsc [label="IPA CCM Identification (Port 3003)"]; + bts <= bsc [label="RSL SACCH filling (SI 5/6)"]; + ...; + bts <= bsc [label="OML (TRX=N) IPA RSL CONNECT"]; + bts => bsc [label="TCP Connect (Port 3003, RSL, TRX N)"]; + bts box bsc [label="IPA CCM Identification (Port 3003)"]; + bts <= bsc [label="RSL SACCH filling (SI 5/6)"]; +} diff --git a/doc/manuals/abis/ipa.adoc b/doc/manuals/abis/ipa.adoc new file mode 100644 index 00000000..9768cdd6 --- /dev/null +++ b/doc/manuals/abis/ipa.adoc @@ -0,0 +1,106 @@ +== IPA Multiplex + +The ETSI/3GPP specifications for A-bis transport (ETSI/3GPP TS 08.56) +specify the transmission of RSL and OML messages over a LAPD based +framing on top of 64kBit/s signalling times slots (B-channels) on E1 +lines. + +OsmoBTS does not implement this LAPD based transport, but instead +implements A-bis over IP in a flavor first observed by ip.access nanoBTS +products. The OsmoBTS implementation is a clean-room re-implementation +based on the observation and dissection of protocol traces. + +LAPD as used in E1 signalling channels provides in-order transmission +and reliable delivery. This is why TCP was chosen as Layer 4 transport +protocol on top of IP. TCP however, is a stream based transport +protocol, which doesn't preserve the boundaries of messages. + +To work around this shortcoming, an additional framing layer called the +IPA multiplex was introduced between TCP and the RSL and OML messages. + +.Protocol Stacking +[width="30%"] +|=== +|RSL + OML (this document) +|IPA (this document) +|TCP (IETF RFC 793) +|IP (IETF RFC 791) +|Ethernet (IEEE 802.3) +|=== + +=== IPA Header + +Each higher-layer PDU is encapsulated by a three-byte IPA header with +the following structure: + +.IPA Header Structure +[options="header",cols="10%,15%,15%,60%"] +|=== +|Offset (Octets)|Length|Name|Description +|0|2|Length|Length of the variable-length payload section in network +byte order (excluding the length of the IPA Header) +|2|1|Stream Identifier|Identifies the stream of the payload +|3|Variable|Payload|higher-layer PDU (i.e. RSL or OML message) +|=== + +=== IPA Stream Identifiers + +The IPA Stream Identifier serves to differentiate different streams +within the multiplex. In the context of A-bis, it can be seen as +analogous to the LAPD TEI on classic A-bis over E1. + +The following IPA stream identifiers are being used in A-bis/IP: + +.IPA Stream Identifiers +[options="header",width="70%",cols="20%,20%,60%"] +|=== +|Value (Hex)|Name|Description +|0x00|RSL|A-bis RSL according to this document, TRX 0 +|0x01|RSL|A-bis RSL according to this document, TRX 1 +|0x0n|RSL|A-bis RSL according to this document, TRX n +|0xfe|CCM|IPA Connection Management +|0xff|OML|A-bis OML according to this document +|=== + + +=== IPA Connection Management (CCM) + +The IPA Connection Management is a sub-layer underneath the IPA +multiplex which is used to manage the connection itself. It supports +functions like Identity Management and Keep-Alive. + +==== Identity Management + +When a BTS connects to the BSC, the BSC must identify the connected BTS +somehow. In ETSI/3GPP A-bis, the E1 multiplex + signalling timeslot +number is used for this. In IP, there is no similar usable identity. +Hence, the Unit ID is used for this purpose. + +.Procedure for IPA peer identification is as follows +[options="header",cols="20%,80%"] +|=== +|Direction|Operation +|BTS -> BSC|BTS connects the TCP connection to be used with IPA +|BTS <- BSC|BSC requests BTS identity with ID_GET +|BTS -> BSC|BTS responds BTS Unit ID with ID_RESP +|BTS <- BSC|BSC responds with ID_ACK, if the Unit ID is known to the BSC +|=== + +Following the above peer identification procedure, transfer of +higher-level messages such as OML or RSL commences. + +==== IPA CCM Messages + +IPA CCM supports the following messages + +.IPA CCM Messages +[options="header"] +[cols="10%,15%,75%"] +|=== +|Value|Name|Purpose +|0x00|PING|Request a PONG from the peer +|0x01|PONG|Response to a PING +|0x04|ID_GET|Request Identity from peer +|0x05|ID_RESP|Response to ID_GET +|0x06|ID_ACK|Identity Acknowledged +|=== diff --git a/doc/manuals/abis/oml-mo-bts.msc b/doc/manuals/abis/oml-mo-bts.msc new file mode 100644 index 00000000..75c283fb --- /dev/null +++ b/doc/manuals/abis/oml-mo-bts.msc @@ -0,0 +1,26 @@ +msc { + bts [label="BTS"], bsc [label="BSC"]; + # this is for the BTS Object + --- [label="Initial state after establishing OML"]; + bts => bsc [label="STATE CHG REP (Disabled/Notinstalled/Locked)"]; + --- [label="MO requests software activation"]; + bts => bsc [label="SW Activate Req"]; + bts <= bsc [label="SW Activate Req Ack"]; + --- [label="BTS instructs BTS to activate software"]; + bts <= bsc [label="Activate SW"]; + bts => bsc [label="Activate SW Ack"]; + --- [label="MO reports new state after SW activation"]; + bts => bsc [label="STATE CHG REP (Disabled/Dependency)"]; + bts => bsc [label="SW Activated Report"]; + --- [label="Configure the MO with its attributes"]; + bts <= bsc [label="Set BTS Attributes"]; + bts => bsc [label="Set BTS Attributes Ack"]; + bts <= bsc [label="OPSTART"]; + bts => bsc [label="OPSTART ACK"]; + --- [label="As this object is locked, we need to unlock it"]; + bts <= bsc [label="Change Adm State (Unlocked)"]; + bts => bsc [label="Change Adm State Ack (Unlocked)"]; + bts => bsc [label="STATE CHG REP (Disabled/Dependency/Unlocked)"]; + --- [label="Initialize Radio Transceiver, Radio Carrier, Channels"]; + bts => bsc [label="STATE CHG REP (Enabled/OK)"]; +} diff --git a/doc/manuals/abis/oml-mo-carrier.msc b/doc/manuals/abis/oml-mo-carrier.msc new file mode 100644 index 00000000..fc5070f6 --- /dev/null +++ b/doc/manuals/abis/oml-mo-carrier.msc @@ -0,0 +1,24 @@ +msc { + bts [label="Radio Carrier"], bsc [label="BSC"]; + --- [label="Initial state after establishing OML"]; + bts => bsc [label="STATE CHG REP (Disabled/Notinstalled/Locked)"]; + --- [label="MO requests software activation"]; + bts => bsc [label="SW Activate Req"]; + bts <= bsc [label="SW Activate Req Ack"]; + --- [label="BTS instructs BTS to activate software"]; + bts <= bsc [label="Activate SW"]; + bts => bsc [label="Activate SW Ack"]; + --- [label="MO reports new state after SW activation"]; + bts => bsc [label="STATE CHG REP (Disabled/Offline)"]; + bts => bsc [label="SW Activated Report"]; + --- [label="Configure the MO with its attributes"]; + bts <= bsc [label="Set Radio Carrier Attributes"]; + bts => bsc [label="Set Radio Carrier Attributes Ack"]; + bts <= bsc [label="OPSTART"]; + bts => bsc [label="OPSTART ACK"]; + --- [label="As this object is locked, we need to unlock it"]; + bts <= bsc [label="Change Adm State (Unlocked)"]; + bts => bsc [label="Change Adm State Ack (Unlocked)"]; + bts => bsc [label="STATE CHG REP (Disabled/OK/Unlocked)"]; + bts => bsc [label="STATE CHG REP (Enabled)"]; +} diff --git a/doc/manuals/abis/oml-mo-channel.msc b/doc/manuals/abis/oml-mo-channel.msc new file mode 100644 index 00000000..624ae724 --- /dev/null +++ b/doc/manuals/abis/oml-mo-channel.msc @@ -0,0 +1,20 @@ +msc { + bts [label="Channel"], bsc [label="BSC"]; + --- [label="Initial state after establishing OML"]; + bts => bsc [label="STATE CHG REP (Disabled/Notinstalled/Locked)"]; + --- [label="MO reports new state after SW activation of Baseband Transceiver"]; + bts => bsc [label="STATE CHG REP (Disabled/Dependency)"]; + bts => bsc [label="SW Activated Report"]; + --- [label="Configure the MO with its attributes"]; + bts <= bsc [label="Set Channel Attributes"]; + bts => bsc [label="Set Channel Attributes Ack"]; + bts <= bsc [label="OPSTART"]; + bts => bsc [label="OPSTART ACK"]; + --- [label="As this object is locked, we need to unlock it"]; + bts <= bsc [label="Change Adm State (Unlocked)"]; + bts => bsc [label="Change Adm State Ack (Unlocked)"]; + bts => bsc [label="STATE CHG REP (Disabled/Dependency/Unlocked)"]; + --- [label="Initialize Radio Carrier / Baseband Transceiver"]; + bts => bsc [label="STATE CHG REP (Disabled/Offline)"]; + bts => bsc [label="STATE CHG REP (Enabled/OK)"]; +} diff --git a/doc/manuals/abis/oml-mo-sitemgr.msc b/doc/manuals/abis/oml-mo-sitemgr.msc new file mode 100644 index 00000000..39e4d159 --- /dev/null +++ b/doc/manuals/abis/oml-mo-sitemgr.msc @@ -0,0 +1,17 @@ +msc { + bts [label="Site Manager"], bsc [label="BSC"]; + # this is for the Site Manager Object + --- [label="Initial state after establishing OML"]; + bts => bsc [label="STATE CHG REP (Disabled/Notinstalled)"]; + --- [label="MO requests software activation"]; + bts => bsc [label="SW Activate Req"]; + bts <= bsc [label="SW Activate Req Ack"]; + --- [label="BTS instructs BTS to activate software"]; + bts <= bsc [label="Activate SW"]; + bts => bsc [label="Activate SW Ack"]; + --- [label="MO reports new state after SW activation"]; + bts => bsc [label="STATE CHG REP (Enabled)"]; + bts => bsc [label="SW Activated Report"]; + bts <= bsc [label="OPSTART"]; + bts => bsc [label="OPSTART ACK"]; +} diff --git a/doc/manuals/abis/oml-mo-transceiver.msc b/doc/manuals/abis/oml-mo-transceiver.msc new file mode 100644 index 00000000..d40e7cc0 --- /dev/null +++ b/doc/manuals/abis/oml-mo-transceiver.msc @@ -0,0 +1,23 @@ +msc { + bts [label="Baseband Transceiver"], bsc [label="BSC"]; + --- [label="Initial state after establishing OML"]; + bts => bsc [label="STATE CHG REP (Disabled/Notinstalled/Locked)"]; + --- [label="MO requests software activation"]; + bts => bsc [label="SW Activate Req"]; + bts <= bsc [label="SW Activate Req Ack"]; + --- [label="BTS instructs BTS to activate software"]; + bts <= bsc [label="Activate SW"]; + bts => bsc [label="Activate SW Ack"]; + --- [label="MO reports new state after SW activation"]; + bts => bsc [label="STATE CHG REP (Disabled/Dependency)"]; + bts => bsc [label="SW Activated Report"]; + --- [label="BSC requests RSL establishment"]; + bts <= bsc [label="IPA RSL Connect"]; + bts => bsc [label="IPA RSL Connect ACK"]; + bts <= bsc [label="OPSTART"]; + bts => bsc [label="OPSTART ACK"]; + --- [label="As this object is locked, we need to unlock it"]; + bts <= bsc [label="Change Adm State (Unlocked)"]; + bts => bsc [label="Change Adm State Ack (Unlocked)"]; + bts => bsc [label="STATE CHG REP (Disabled/Dependency/Unlocked)"]; +} diff --git a/doc/manuals/abis/oml-startup.msc b/doc/manuals/abis/oml-startup.msc new file mode 100644 index 00000000..de5d0392 --- /dev/null +++ b/doc/manuals/abis/oml-startup.msc @@ -0,0 +1,34 @@ +msc { + hscale = 2; + + chan [label="Channel"], rc [label="Radio Carrier"], smg [label="Site Manager"], bts [label="BTS"], bsc [label="BSC"]; + + bts => bsc [label="TCP Connect (Port 3003, OML)"]; + bts box bsc [label="IPA CCM Identification (Port 3003)"]; + |||; + smg => bsc [label="(Site Mgr) STATE CHG REP (Disabled/NotInstalled)"]; + bts => bsc [label="(BTS) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + rc => bsc [label="(TRANSC) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 0) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 1) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 2) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 3) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 4) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 5) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 6) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + chan => bsc [label="(Ch 7) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + rc => bsc [label="(RC) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + bts => bsc [label="(GPRS-NSE) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + bts => bsc [label="(GPRS-CELL) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + bts => bsc [label="(GPRS-NSVC0) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + bts => bsc [label="(GPRS-NSVC1) STATE CHG REP (Disabled/NotInstalled/Locked)"]; + |||; + smg => bsc [label="(Site Mgr) SW Activate Req"]; + smg <= bsc [label="(Site Mgr) SW Activate Req Ack"]; + smg <= bsc [label="(Site Mgr) Activate SW"]; + smg => bsc [label="(Site Mgr) Activate SW Ack"]; + smg => bsc [label="(Site Mgr) STATE CHG REP (Enabled)"]; + smg => bsc [label="(Site Mgr) SW Activated Report"]; + smg <= bsc [label="(Site Mgr) OPSTART"]; + smg => bsc [label="(Site Mgr) OPSTART ACK"]; +} diff --git a/doc/manuals/abis/oml-startup2.msc b/doc/manuals/abis/oml-startup2.msc new file mode 100644 index 00000000..8a97e124 --- /dev/null +++ b/doc/manuals/abis/oml-startup2.msc @@ -0,0 +1,50 @@ +msc { + hscale = 2; + + chan [label="Channel"], rc [label="Radio Carrier"], bts [label="BTS"], bsc [label="BSC"]; + + bts box bsc [label="OML Connect + Site Manager Init"]; + ...; + bts => bsc [label="(BTS) SW Activate Req"]; + bts <= bsc [label="(BTS) SW Activate Req Ack"]; + bts <= bsc [label="(BTS) Activate SW"]; + bts => bsc [label="(BTS) Activate SW Ack"]; + bts => bsc [label="(BTS) STATE CHG REP (Disabled/Dependency)"]; + bts => bsc [label="(BTS) SW Activated Report"]; + |||; + rc => bsc [label="(TRANSC) SW Activate Req"]; + rc => bsc [label="(RC) SW Activated Req"]; + |||; + bts <= bsc [label="(BTS) Set BTS Attributes"]; + bts => bsc [label="(BTS) Set BTS Attributes Ack"]; + bts <= bsc [label="(BTS) OPSTART"]; + bts => bsc [label="(BTS) OPSTART Ack"]; + |||; + bts <= bsc [label="(BTS) Change Adm State (Unlocked)"]; + bts => bsc [label="(BTS) Change Adm State ACK (Unlocked)"]; + bts => bsc [label="(BTS) STATE CHG REP (Disabled/Dependency/Unlcoked)"]; + |||; + rc <= bsc [label="(TRANSC) SW Activate Req Ack"]; + rc <= bsc [label="(TRANSC) Activate SW"]; + rc => bsc [label="(TRANSC) Activate SW Ack"]; + rc => bsc [label="(TRANSC) STATE CHG REP (Disabled/Dependency)"]; + rc => bsc [label="(TRANSC) SW Activated Report"]; + + chan => bsc [label="(CHAN 0) STATE CHG REP (Disabled/Dependency)"]; + chan => bsc [label="(CHAN 1) STATE CHG REP (Disabled/Dependency)"]; + chan => bsc [label="(CHAN 2) STATE CHG REP (Disabled/Dependency)"]; + chan => bsc [label="(CHAN 3) STATE CHG REP (Disabled/Dependency)"]; + chan => bsc [label="(CHAN 4) STATE CHG REP (Disabled/Dependency)"]; + chan => bsc [label="(CHAN 5) STATE CHG REP (Disabled/Dependency)"]; + chan => bsc [label="(CHAN 6) STATE CHG REP (Disabled/Dependency)"]; + chan => bsc [label="(CHAN 7) STATE CHG REP (Disabled/Dependency)"]; + |||; + chan => bsc [label="(CHAN 0) SW Activated Report"]; + chan => bsc [label="(CHAN 1) SW Activated Report"]; + chan => bsc [label="(CHAN 2) SW Activated Report"]; + chan => bsc [label="(CHAN 3) SW Activated Report"]; + chan => bsc [label="(CHAN 4) SW Activated Report"]; + chan => bsc [label="(CHAN 5) SW Activated Report"]; + chan => bsc [label="(CHAN 6) SW Activated Report"]; + chan => bsc [label="(CHAN 7) SW Activated Report"]; +} diff --git a/doc/manuals/abis/oml-startup3.msc b/doc/manuals/abis/oml-startup3.msc new file mode 100644 index 00000000..c1fffd2c --- /dev/null +++ b/doc/manuals/abis/oml-startup3.msc @@ -0,0 +1,51 @@ +msc { + hscale = 2; + + chan [label="Channel"], rc [label="Radio Carrier"], bts [label="BTS"], bsc [label="BSC"]; + + ...; + rc <= bsc [label="(RC) SW Activate Req Ack"]; + rc <= bsc [label="(RC) Activate SW"]; + rc => bsc [label="(RC) Activate SW Ack"]; + rc => bsc [label="(RC) STATE CHG REP (Disabled/Offline)"]; + rc => bsc [label="(RC) SW Activated Report"]; + rc <= bsc [label="(TRANSC) IPA RSL Connect"]; + rc => bsc [label="(TRANSC) IPA RSL Connect Ack"]; + rc <= bsc [label="(TRANSC) OPSTART"]; + rc => bsc [label="(TRANSC) OPSTART Ack"]; + rc <= bsc [label="(TRANSC) Change Adm State (Unlocked)"]; + rc => bsc [label="(TRANSC) Change Adm State Ack (Unlocked)"]; + rc => bsc [label="(TRANSC) STATE CHG REP (Disabled/Dependency/Unlocked)"]; + |||; + chan <= bsc [label="(CHAN 0) Set Channel Attributes"]; + chan => bsc [label="(CHAN 0) Set Channel Attributes Ack"]; + chan <= bsc [label="(CHAN 0) OPSTART"]; + chan => bsc [label="(CHAN 0) OPSTART Ack"]; + chan <= bsc [label="(CHAN 0) Change Adm State (Unlocked)"]; + chan => bsc [label="(CHAN 0) Change Adm State Ack (Unlocked)"]; + chan => bsc [label="(CHAN 0) STATE CHG REP (Disabled/Dependency/Unlocked)"]; + ...; + chan <= bsc [label="(CHAN 7) Set Channel Attributes"]; + chan => bsc [label="(CHAN 7) Set Channel Attributes Ack"]; + chan <= bsc [label="(CHAN 7) OPSTART"]; + chan => bsc [label="(CHAN 7) OPSTART Ack"]; + chan <= bsc [label="(CHAN 7) Change Adm State (Unlocked)"]; + chan => bsc [label="(CHAN 7) Change Adm State Ack (Unlocked)"]; + chan => bsc [label="(CHAN 7) STATE CHG REP (Disabled/Dependency/Unlocked)"]; + |||; + rc <= bsc [label="(RC) Set Radio Carrier Attributes"]; + rc => bsc [label="(RC) Set Radio Carrier Attributes Ack"]; + rc <= bsc [label="(RC) OPSTART"]; + rc => bsc [label="(RC) OPSTART Ack"]; + rc <= bsc [label="(RC) Change Adm State (Unlocked)"]; + rc => bsc [label="(RC) Change Adm State Ack (Unlocked)"]; + rc => bsc [label="(RC) STATE CHG REP (Disabled/OK/Unlocked)"]; + rc => bsc [label="(RC) STATE CHG REP (Enabled)"]; + rc => bsc [label="(TRANSC) STATE CHG REP (Disabled/Offline)"]; + rc => bsc [label="(TRANSC) STATE CHG REP (Enabled/OK)"]; + |||; + chan => bsc [label="(CHAN 0) STATE CHG REP (Disabled/Offline)"]; + chan => bsc [label="(CHAN 0) STATE CHG REP (Enabled/OK)"]; + |||; + bts => bsc [label="(BTS) STATE CHG REP (Enabled/OK)"]; +} diff --git a/doc/manuals/abis/oml.adoc b/doc/manuals/abis/oml.adoc new file mode 100644 index 00000000..778a084b --- /dev/null +++ b/doc/manuals/abis/oml.adoc @@ -0,0 +1,937 @@ +== Organization & Maintenance Link (OML) + +=== List of Messages + +The following tables list the OML messages used by OsmoBTS, grouped by their +level of compliance with 3GPP TS 12.21. + +==== Messages Compliant With TS 12.21 + +Specific limitations apply, see the linked sections. + +.Messages compliant with TS 12.21 +[options="header",cols="10%,10%,20%,35%,5%,20%"] +|=== +| TS 12.21 § | type code (hex) | This document § | Message | <-/-> | Received/Sent by OsmoBTS +6+<| *SW Download Management Messages:* +| 8.3.7 | 0x10 | <<sw_act_rep>> | SW Activated Report | -> | Sent +6+<| *Air Interface Management Messages:* +.3+.| 8.6.1 | 0x41 .3+.| <<set_bts_attr>> | Set BTS Attributes | <- | Received + | 0x42 | Set BTS Attributes Ack | -> | Sent + | 0x43 | Set BTS Attributes Nack | -> | Sent +.3+.| 8.6.2 | 0x44 .3+.| <<set_radio_attr>> | Set Radio Carrier Attributes | <- | Received + | 0x45 | Set Radio Carrier Attributes Ack | -> | Sent + | 0x46 | Set Radio Carrier Attributes Nack | -> | Sent +.3+.| 8.6.3 | 0x47 .3+.| <<set_chan_attr>> | Set Channel Attributes | <- | Received + | 0x48 | Set Channel Attributes Ack | -> | Sent + | 0x49 | Set Channel Attributes Nack | -> | Sent +6+<| *State Management and Event Report Messages:* + | 8.8.1 | 0x61 | <<state_changed_rep>> | State Changed Event Report | -> | Sent +.3+.| 8.8.5 | 0x69 .3+.| <<chg_adm_state>> | Change Administrative State | <- | Received + | 0x6A | Change Administrative State Ack | -> | Sent + | 0x6B | Change Administrative State Nack | -> | Sent +6+<| *Equipment Management Messages:* +.3+.| 8.9.2 | 0x74 .3+.| <<opstart>> | Opstart | <- | Received + | 0x75 | Opstart Ack | -> | Sent + | 0x76 | Opstart Nack | -> | Sent +|=== + + +==== Messages Specific to OsmoBTS + +.Messages specific to OsmoBTS, not found in 3GPP TS 12.21 +[options="header"] +[options="header",cols="20%,55%,5%,20%"] +|=== +| This document § | Message | <-/-> | Received/Sent by OsmoBTS +| <<ipacc_set_attr>> | Set Attribute | <- | Received +|=== + + +==== Messages Not Implemented by OsmoBTS +.3GPP TS 12.21 messages not implemented by OsmoBTS +[options="header",cols="10%,10%,80%"] +|=== +| TS 12.21 § | type code (hex) | Message +3+<| *SW Download Management Messages:* +.3+.| 8.3.1 | 0x01 | Load Data Initiate + | 0x02 | Load Data Initiate Ack + | 0x03 | Load Data Initiate Nack +.2+.| 8.3.2 | 0x04 | Load Data Segment + | 0x05 | Load Data Segment Ack + | 8.3.3 | 0x06 | Load Data Abort +.3+.| 8.3.4 | 0x07 | Load Data End + | 0x08 | Load Data End Ack + | 0x09 | Load Data End Nack +.3+.| 8.3.5 | 0x0A | SW Activate Request + | 0x0B | SW Activate Request Ack + | 0x0C | SW Activate Request Nack +.3+.| 8.3.6 | 0x0D | Activate SW + | 0x0E | Activate SW Ack + | 0x0F | Activate SW Nack +3+<| *A-bis Interface Management Messages:* +.3+.| 8.4.1 | 0x21 | Establish TEI + | 0x22 | Establish TEI Ack + | 0x23 | Establish TEI Nack +.3+.| 8.4.2 | 0x24 | Connect Terrestrial Signalling + | 0x25 | Connect Terrestrial Signalling Ack + | 0x26 | Connect Terrestrial Signalling Nack +.3+.| 8.4.3 | 0x27 | Disconnect Terrestrial Signalling + | 0x28 | Disconnect Terrestrial Signalling Ack + | 0x29 | Disconnect Terrestrial Signalling Nack +.3+.| 8.4.4 | 0x2A | Connect Terrestrial Traffic + | 0x2B | Connect Terrestrial Traffic Ack + | 0x2C | Connect Terrestrial Traffic Nack +.3+.| 8.4.5 | 0x2D | Disconnect Terrestrial Traffic + | 0x2E | Disconnect Terrestrial Traffic Ack + | 0x2F | Disconnect Terrestrial Traffic Nack +3+<| *Transmission Management Messages:* +.3+.| 8.5.1 | 0x31 | Connect Multi-Drop Link + | 0x32 | Connect Multi-Drop Link Ack + | 0x33 | Connect Multi-Drop Link Nack +.3+.| 8.5.2 | 0x34 | Disconnect Multi-Drop Link + | 0x35 | Disconnect Multi-Drop Link Ack + | 0x36 | Disconnect Multi-Drop Link Nack +3+<| *Test Management Messages:* +.3+.| 8.7.1 | 0x51 | Perform Test + | 0x52 | Perform Test Ack + | 0x53 | Perform Test Nack +.3+.| 8.7.2 | 0x54 | Test Report + | 0x55 | Send Test Report + | 0x56 | Send Test Report Ack + | 8.7.3 | 0x57 | Send Test Report Nack +.3+.| 8.7.4 | 0x58 | Stop Test + | 0x59 | Stop Test Ack + | 0x5A | Stop Test Nack +3+<| *State Management and Event Report Messages:* + | 8.8.2 | 0x62 | Failure Event Report +.3+.| 8.8.3 | 0x63 | Stop Sending Event Reports + | 0x64 | Stop Sending Event Reports Ack + | 0x65 | Stop Sending Event Reports Nack +.3+.| 8.8.4 | 0x66 | Restart Sending Event Reports + | 0x67 | Restart Sending Event Reports Ack + | 0x68 | Restart Sending Event Reports Nack +.3+.| 8.8.6 | 0x6C | Change Administrative State Request + | 0x6D | Change Administrative State Request Ack + | 0x6E | Change Administrative State Request Nack +.3+.| 8.8.7 | 0x93 | Report Outstanding Alarms + | 0x94 | Report Outstanding Alarms Ack + | 0x95 | Report Outstanding Alarms Nack +3+<| *Equipment Management Messages:* +.3+.| 8.9.1 | 0x71 | Changeover + | 0x72 | Changeover Ack + | 0x73 | Changeover Nack +.3+.| 8.9.3 | 0x87 | Reinitialize + | 0x88 | Reinitialize Ack + | 0x89 | Reinitialize Nack +.3+.| 8.9.4 | 0x77 | Set Site Outputs + | 0x78 | Set Site Outputs Ack + | 0x79 | Set Site Outputs Nack +.3+.| 8.9.5 | 0x90 | Change HW Configuration + | 0x91 | Change HW Configuration Ack + | 0x92 | Change HW Configuration Nack +3+<| *Measurement Management Messages:* + | 8.10.1 | 0x8A | Measurement Result Request + | 8.10.2 | 0x8B | Measurement Result Response + | 8.10.3 | 0x8C | Stop Measurement + | 8.10.4 | 0x8D | Start Measurement +3+<| *Other Messages:* + | 8.11.1 | 0x81 | Get Attributes + | 8.11.3 | 0x82 | Get Attribute(s) Response + | 8.11.1 | 0x83 | Get Attributes Nack +.3+.| 8.11.2 | 0x84 | Set Alarm Threshold + | 0x85 | Set Alarm Threshold Ack + | 0x86 | Set Alarm Threshold Nack +|=== + + +=== Details on Compliant OML Messages + +[[sw_act_rep]] +==== SW Activated Report + +OsmoBTS will send an _SW Activated Report_ when RF has been activated +successfully. The message is compliant with 3GPP TS 12.21 § 8.3.7. + +Upon RF activation, two _SW Activated Report_ messages will be sent, for the Object Classes + +- Radio Carrier (0x02) +- Baseband Transceiver (0x04) + +[[set_bts_attr]] +==== Set BTS Attributes + +OsmoBTS will receive a _Set BTS Attributes_ message and reply with a +corresponding ACK message on success. IE handling is fully compliant to TS +12.21, except that a change of BCCH ARFCN or BSIC while in operation is not +supported, and hence the _Starting Time_ IE is rejected. + +._Set BTS Attributes_ IEs not handled by OsmoBTS +[options="header",cols="10%,30%,60%"] +|=== +| TS 12.21 § | IE Name | Handling +| 9.4.52 | Starting Time | not supported (provokes NACK cause 0x10) +|=== + + +[[set_radio_attr]] +==== Set Radio Carrier Attributes + +This message conforms to 3GPP TS 12.21, with the following limitation, +as frequency hopping is not supported by OsmoBTS: + +._Set Radio Carrier Attributes_ IE limitations +[options="header",cols="10%,30%,60%"] +|=== +| TS 12.21 § | IE Name | Handling +| 9.4.5 | ARFCN List | ignored +|=== + + +[[set_chan_attr]] +==== Set Channel Attributes + +This message conforms to 3GPP TS 12.21, with the following limitation: OpenBTS +does not support frequency hopping, and the following 3GPP TS 12.21 IEs provoke +a NACK response when sent to OsmoBTS, as frequency hopping is not +supported: + +._Set Channel Attributes_ IE limitations +[options="header",cols="10%,30%,60%"] +|=== +| TS 12.21 § | IE Name | Handling +| 9.4.21 | HSN | not supported (provokes NACK cause 0x10) +| 9.4.27 | MAIO | not supported (provokes NACK cause 0x10) +| 9.4.52 | Starting Time | not supported (provokes NACK cause 0x10) +|=== + +[[state_changed_rep]] +==== State Changed Event Report + +This message is compliant with 3GPP TS 12.21. Exactly these IEs are sent by +OsmoBTS: + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message Type (0xf5) | 3GPP TS 12.21 9.1 | M | V | 1 +| Object Class | 3GPP TS 12.21 9.2 | M | V | 1 +| Object Instance | 3GPP TS 12.21 9.3 | M | V | 3 +| Operational State | 3GPP TS 12.21 9.4.38 | O | TV | 2 +| Availability Status | 3GPP TS 12.21 9.4.7 | O | TL16V (with length of 1) | 3 +|=== + +[[chg_adm_state]] +==== Change Administrative State + +This message is compliant with 3GPP TS 12.21 § 8.8.5. It applies to all of the +Objects Classes defined in 3GPP TS 12.21 § 9.2 as well as +<<addnl_obj_classes>>. + +[[opstart]] +==== Opstart + +This message is compliant with 3GPP TS 12.21 § 8.9.2. It applies to all of the +Objects Classes defined in 3GPP TS 12.21 § 9.2 as well as +<<addnl_obj_classes>>. + + +=== Details on OsmoBTS Specific Messages + +[[ipacc_set_attr]] +==== Set Attribute + +The message type is 0xf5. This message is sent to OsmoBTS to set +attributes on instances of managed objects of the non-standard +additional Object Classes (see <<addnl_obj_classes>>). + +The message specifics depend on the Object Class and are detailed in +<<addnl_obj_classes>>. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message Type (0xf5) | 3GPP TS 12.21 9.1 | M | V | 1 +| Object Class | 3GPP TS 12.21 9.2 | M | V | 1 +| Object Instance | 3GPP TS 12.21 9.3 | M | V | 3 +5+<| _Object Class specific IEs follow, see <<addnl_obj_classes>>..._ +|=== + + +[[addnl_obj_classes]] +=== Additional Object Classes + +In addition to 3GPP TS 12.21 Chapter 9.2, the following managed objects +are supported: + +.Additional Managed Object Classes +[options="header"] +[cols="20%,20%,60%"] +|=== +| Value | Name | Description +| 0xf0 | GPRS NSE | GPRS-NS Entity +| 0xf1 | GPRS CELL | GPRS Cell Entity +| 0xf2 | GPRS NSVC | GPRS NS Virtual Circuit +|=== + +==== GPRS-NSE Managed Object + +There is one NS Entity per BTS. It supports the *Set Attribute* message +with the following Information Elements: + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message Type | 3GPP TS 12.21 9.1 | M | V | 1 +| Object Class | 3GPP TS 12.21 9.2 | M | V | 1 +| Object Instance | 3GPP TS 12.21 9.3 | M | V | 3 +| GPRS NSEI | <<NM_ATT_IPACC_NSEI>> | O | TL16V | >= 5 +| GPRS NS Configuration | <<NM_ATT_IPACC_NS_LINK_CFG>> | O | TL16V | >= 10 +| GPRS BSSGP Configuration | <<NM_ATT_IPACC_BSSGP_CFG>> | O | TL16V | >= 14 +|=== + +==== GPRS Cell Managed Object + +There is one GPRS Cell entity per BTS. It supports the *Set Attribute* +message with the following Information Elements: + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message Type | 3GPP TS 12.21 9.1 | M | V | 1 +| Object Class | 3GPP TS 12.21 9.2 | M | V | 1 +| Object Instance | 3GPP TS 12.21 9.3 | M | V | 3 +| GPRS Routing Area Code | <<NM_ATT_IPACC_RAC>> | O | TL16V | >= 4 +| GPRS Paging Configuration | <<NM_ATT_IPACC_GPRS_PAGING_CFG>> | O | TL16V | >= 5 +| GPRS RLC Configuration | <<NM_ATT_IPACC_RLC_CFG>> | O | TL16V | >= 12 +| GPRS Coding Schemes | <<NM_ATT_IPACC_CODING_SCHEMES>> | O | TL16V | >= 5 +| GPRS RLC Configuration 2 | <<NM_ATT_IPACC_RLC_CFG_2>> | O | TL16V | >= 8 +| GPRS RLC Configuration 3 | <<NM_ATT_IPACC_RLC_CFG_3>> | O | TL16V | >= 4 +|=== + +==== GPRS NS-VC Managed Object + +There are two GPRS NS-VC instances per BTS. It supports the *Set +Attribute* message with the following Information Elements: + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message Type | 3GPP TS 12.21 9.1 | M | V | 1 +| Object Class | 3GPP TS 12.21 9.2 | M | V | 1 +| Object Instance | 3GPP TS 12.21 9.3 | M | V | 3 +| GPRS NSVCI | <<NM_ATT_IPACC_NSVCI>> | O | TL16V | >= 5 +| GPRS NS Link Configuration | <<NM_ATT_IPACC_NS_LINK_CFG>> | O | TL16V | >= 11 +|=== + + +=== Information Elements Overview + +All of the IEs handled by OsmoBTS are listed below, with limitations and +additions to TS 12.21 specified in more detail. + +==== IEs Conforming to TS 12.21 + +The following Information Elements are accepted by OsmoBTS. Not all IEs are +actually evaluated. + +.IEs conforming to TS 12.21 +[options="header",cols="5%,10%,40%,5%,40%"] +|=== +| tag (hex) | TS 12.21 § | IE name | <-/-> | Received/Sent by OsmoBTS +| 0x00 | 9.4.1 | Abis Channel | | _ignored_ +| 0x01 | 9.4.2 | Additional Info | | _ignored_ +| 0x02 | 9.4.3 | Additional Text | | _ignored_ +| 0x03 | 9.4.4 | Administrative State | <- -> | Received & Sent +| 0x04 | 9.4.5 | ARFCN List | <- | Received, with exactly 1 ARFCN: see <<NM_ATT_ARFCN_LIST>>; + ignored by _Set Radio Attribute_ message (<<set_radio_attr>>) +| 0x05 | 9.4.6 | Autonomously Report | | _ignored_ +| 0x06 | 9.4.7 | Availability Status | -> | Sent +| 0x07 | 9.4.8 | BCCH ARFCN | <- | Received +| 0x08 | 9.4.9 | BSIC | <- | Received +| 0x09 | 9.4.10 | BTS Air Timer | <- | Received +| 0x0a | 9.4.11 | CCCH Load Indication Period | <- | Received +| 0x0b | 9.4.12 | CCCH Load Threshold | <- | Received +| 0x0c | 9.4.13 | Channel Combination | <- | Received, with additional channel combinations: see <<ie_chan_comb>> +| 0x0d | 9.4.14 | Connection Failure Criterion | <- | Received, with limitations see <<ie_conn_fail_crit>> +| 0x0e | 9.4.15 | Destination | | _ignored_ +| 0x0f | 9.4.16 | Event Type | | _ignored_ +| 0x11 | 9.4.17 | File Data | | _ignored_ +| 0x12 | 9.4.18 | File Id | | _ignored_ +| 0x13 | 9.4.19 | File Version | | _ignored_ +| 0x14 | 9.4.20 | GSM Time | | _ignored_ +| 0x16 | 9.4.22 | HW Configuration | | _ignored_ +| 0x18 | 9.4.24 | Intave Parameter | <- | _ignored_ +| 0x19 | 9.4.25 | Interference level Boundaries | <- | _ignored_ +| 0x1a | 9.4.26 | List of Required Attributes | | _ignored_ +| 0x1c | 9.4.28 | Manufacturer Dependent State | | _ignored_ +| 0x1d | 9.4.29 | Manufacturer Dependent Thresholds | | _ignored_ +| 0x1e | 9.4.30 | Manufacturer Id | | _ignored_ +| 0x1f | 9.4.31 | Max Timing Advance | <- | Received +| 0x20 | 9.4.34 | Multi-drop BSC Link | | _ignored_ +| 0x21 | 9.4.35 | Multi-drop next BTS Link | | _ignored_ +| 0x22 | 9.4.36 | Nack Causes | -> | Sent +| 0x23 | 9.4.37 | Ny1 | <- | Received +| 0x24 | 9.4.38 | Operational State | -> | Sent +| 0x25 | 9.4.39 | Overload Period | <- | _ignored_ +| 0x26 | 9.4.40 | Physical Config | | _ignored_ +| 0x27 | 9.4.41 | Power Class | | _ignored_ +| 0x28 | 9.4.42 | Power Output Thresholds | | _ignored_ +| 0x29 | 9.4.43 | Probable Cause | | _ignored_ +| 0x2a | 9.4.44 | RACH Busy Threshold | <- | Received +| 0x2b | 9.4.45 | RACH Load Averaging Slots | <- | _ignored_ +| 0x2c | 9.4.46 | Radio Sub Channel | | _ignored_ +| 0x2d | 9.4.47 | RF Max Power Reduction | <- | Received +| 0x2e | 9.4.48 | Site Inputs | | _ignored_ +| 0x2f | 9.4.49 | Site Outputs | | _ignored_ +| 0x30 | 9.4.50 | Source | | _ignored_ +| 0x31 | 9.4.51 | Specific Problems | | _ignored_ +| 0x33 | 9.4.53 | T200 | <- | _ignored_ (1s on DCCH, 2s on ACCH) +| 0x34 | 9.4.54 | TEI | | _ignored_ +| 0x35 | 9.4.55 | Test Duration | | _ignored_ +| 0x36 | 9.4.56 | Test No | | _ignored_ +| 0x37 | 9.4.57 | Test Report Info | | _ignored_ +| 0x38 | 9.4.58 | VSWR Thresholds | | _ignored_ +| 0x39 | 9.4.59 | Window Size | | _ignored_ +| 0x40 | 9.4.60 | TSC | <- | Received, with limitations: see <<NM_ATT_TSC>> +| 0x41 | 9.4.61 | SW Configuration | | _ignored_ +| 0x43 | 9.4.63 | Perceived Severity | | _ignored_ +| 0x44 | 9.4.64 | Get Attribute Response Info | | _ignored_ +| 0x45 | 9.4.65 | Outstanding Alarm Sequence | | _ignored_ +| 0x46 | 9.4.66 | HW Conf Change Info | | _ignored_ +| 0x47 | 9.4.32 | Measurement Result | | _ignored_ +|=== + +==== IEs Not Conforming to TS 12.21 + +.IEs not conforming to TS 12.21 +[options="header",cols="5%,10%,30%,55%"] +|=== +| tag (hex) | TS 12.21 § | IE name | Description +| 0x15 | 9.4.21 | HSN | presence causes NACK response +| 0x17 | 9.4.23 | HW Description | _ignored_ by OsmoBTS, but coding may differ, see <<ie_hw_desc>> +| 0x1b | 9.4.27 | MAIO | presence causes NACK response +| 0x32 | 9.4.52 | Starting Time | presence causes NACK response +| 0x42 | 9.4.62 | SW Description | not supported +| 0x48 | 9.4.33 | Measurement Type | not supported +|=== + + +==== Additional Attributes and Parameters + +The following Information Elements are defined in addition to those +specified in 3GPP TS 12.21 Chapter 9.4. + +All of these additional IEs are _received_ by OsmoBTS. + +The content of these attributes is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + +.Additional IEs handled by OsmoBTS but not defined in TS 12.21 +[options="header",cols="5%,50%,45%"] +|=== +| tag (hex) | IE name | Description +| 0x80 | RSL Destination IP Address | <<NM_ATT_IPACC_DST_IP>> +| 0x81 | RSL Destination TCP Port | <<NM_ATT_IPACC_DST_IP_PORT>> +| 0x85 | RSL IPA Stream ID | <<NM_ATT_IPACC_STREAM_ID>> +| 0x9a | GPRS Routing Area Code | <<NM_ATT_IPACC_RAC>> +| 0x9c | GPRS Paging Configuration | <<NM_ATT_IPACC_GPRS_PAGING_CFG>> +| 0x9d | GPRS NSEI | <<NM_ATT_IPACC_NSEI>> +| 0x9e | GPRS BVCI | <<NM_ATT_IPACC_BVCI>> +| 0x9f | GPRS NSVCI | <<NM_ATT_IPACC_NSVCI>> +| 0xa0 | GPRS NS Configuration | <<NM_ATT_IPACC_NS_CFG>> +| 0xa1 | GPRS BSSGP Configuration | <<NM_ATT_IPACC_BSSGP_CFG>> +| 0xa2 | GPRS NS Link Configuration | <<NM_ATT_IPACC_NS_LINK_CFG>> +| 0xa3 | GPRS RLC Configuration | <<NM_ATT_IPACC_RLC_CFG>> +| 0xa8 | GPRS Coding Schemes | <<NM_ATT_IPACC_CODING_SCHEMES>> +| 0xa9 | GPRS RLC Configuration 2 | <<NM_ATT_IPACC_RLC_CFG_2>> +| 0xac | GPRS RLC Configuration 3 | <<NM_ATT_IPACC_RLC_CFG_3>> +|=== + + +=== Details on IEs + +[[ie_hw_desc]] +==== HW Description + +TS 12.21 suggests a series of 5 length-value pairs for the _HW Description_ IE. +Instead, OsmoBTS interprets it as a single TL16V. The value of this IE is +ignored by OsmoBTS, yet the coding may affect message parsing. + +[width="40%",cols="90%,10%"] +[grid="none"] +|=== +| Attribute Identifier (0x17) | 1 +| Length | 2-3 +| Ignored | N +|=== + + +[[NM_ATT_ARFCN_LIST]] +==== ARFCN List + +Since OsmoBTS does not support frequency hopping, the _ARFCN List_ must contain +exactly one ARFCN. + +[[ie_chan_comb]] +==== Additional Channel Combinations + +In addition to 3GPP TS 12.21 Chapter 9.4.13, the following channel +combinations are supported: + +.Additional Channel Combinations +[options="header"] +[cols="10%,90%"] +|=== +| Value | Description +| 0x0b | Reserved for PBCCH + PCCCH + PDTCH/F + PACCH/F + PTCCH/F +| 0x0c | Reserved for PBCCH + PDTCH/F + PACCH/F + PTCCH/F +| 0x0d | PDTCH/F + PACCH/F + PTCCH/F +| 0x80 | Reserved for Dynamic TCH/F / PDCH +| 0x81 | Reserved for Dynamic TCH/F / TCH/H +|=== + +[[ie_conn_fail_crit]] +==== Connection Fail Criterion + +3GPP TS 12.21 Chapter 9.4.14 specifies two different options for the +_Connection Failure Criterion_. OsmoBTS only implements the option +coded as 0x01, i.e. based upon uplink SACCH error rate +(RADIO_LINK_TIMEOUT). + +[[NM_ATT_TSC]] +==== TSC + +Due to limitations in the currently supported PHY implementations, +OsmoBTS supports only one global TSC for all channels on one TRX, rather +than a separate TSC for each timeslot, as expected by 3GPP TS 12.21. + + +[[NM_ATT_IPACC_DST_IP]] +==== RSL Destination IP Address + +The value part of this attribute has a length of 4 octets and is encoded +as IPv4 address in network byte order. + +[width="40%",cols="90%,10%"] +[grid="none"] +|=== +| Attribute Identifier (0x80) | 1 +| IPv4 Address (MSB first) | 2-5 +|=== + + +[[NM_ATT_IPACC_DST_IP_PORT]] +==== RSL Destination TCP Port + +The value part of this attribute has a length of 2 octets and contains +the TCP destination port for the RSL connection, encoded in network byte +order. + +[width="40%",cols="90%,10%"] +[grid="none"] +|=== +| Attribute Identifier (0x81) | 1 +| Port number (MSB first) | 2-3 +|=== + + +[[NM_ATT_IPACC_STREAM_ID]] +==== RSL IPA Stream ID + +The value part of this attribute has a length of one octet and specifies +the IPA stream ID to be used for the RSL connection of this TRX. + +[width="40%",cols="90%,10%"] +[grid="none"] +|=== +| Attribute Identifier (0x85) | 1 +| Stream ID | 2 +|=== + + +[[NM_ATT_IPACC_RAC]] +==== GPRS Routing Area Code + +The value part of the GPRS Routing Area code consist of a single octet +encoding the GPRS Routing Area Code. + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_GPRS_PAGING_CFG]] +==== GPRS Paging Configuration + +The value part of this attribute consists of two octets encoded as +follows: + +[options="header"] +[cols="10%,90%"] +|=== +| Offset | Description +| 0 | GPRS Paging repeat time in units of 50ms intervals +| 1 | GPRS Paging repeat count +|=== + + +[[NM_ATT_IPACC_NSEI]] +==== GPRS NSEI + +The value part of the GPRS NSEI is encoded as 16bit integer value in +network byte order. + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_BVCI]] +==== GPRS BVCI + +The value part of this attribute consists of two octets encoding the +BSSGP Virtual Circuit Identifier (BVCI) as unsigned 16 bit integer in +network byte order. + + +[[NM_ATT_IPACC_NSVCI]] +==== GPRS NSVCI + +The value part of the GPRS NSVCI attribute is a 16bit unsigned integer +in network byte order, encoding the GPRS NSVCI as specified in 3GPP TS +08.16. + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_NS_CFG]] +==== GPRS NS Configuration + +The value part of the GPRS NS Configuration consist of an array of 7 octets, each +describing one GPRS NS related timer: + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_BSSGP_CFG]] +==== GPRS BSSGP Configuration + +The value part of the GPRS BSSGP configuration consists of an array of +11 octets, each describing one GPRS BSSGP related timer: + +[options="header"] +[cols="10%,90%"] +|=== +| Offset | Description +| 0 | Blocking Timer (T1) +| 1 | Blocking Retries +| 2 | Unblocking Retries +| 3 | Reset Timer (T2) +| 4 | Reset Retries +| 5 | Suspend Timer (T3) in units of 100ms +| 6 | Suspend Retries +| 7 | Resume Timer (T4) in units of 100ms +| 8 | Resume Retries +| 9 | Capability Update Timer (T5) +| 10 | Capability Update Retries +|=== + +The detailed description of the meaning of those timers is given in the +GPRS BSSGP specification 3GPP TS 08.18. + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_NS_LINK_CFG]] +==== GPRS NS Link Configuration + +The content of this attribute is 8 octets long and encoded as follows: +[options="header"] +[cols="10%,10%,80%"] +|=== +| Offset | Length | Description +| 0 | 2 | GPRS-NS Remote UDP Port Number (SGSN side) +| 2 | 4 | GPRS-NS Remote IPv4 Address (SGSN side) +| 6 | 2 | GPRS-NS Local UDP Port Number (BTS side) +|=== + +All values are encoded in network byte order. + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_RLC_CFG]] +==== GPRS RLC Configuration + +The value part of the GPRS RLC Configuration consists of an array of 9 +octets, each describing a RLC timer: + +[options="header"] +[width="60%",cols="10%,80%,10%"] +|=== +| Offset | Description | Unit +| 0 | GPRS RLC Timer T3142 | s +| 1 | GPRS RLC Timer T3169 | s +| 2 | GPRS RLC Timer T3191 | s +| 3 | GPRS RLC Timer T3193 | 10ms +| 4 | GPRS RLC Timer T3195 | s +| 5 | GPRS RLC Timer T3101 | s +| 6 | GPRS RLC Timer T3103 | s +| 7 | GPRS RLC Timer T3105 | s +| 8 | GPRS RLC CV Countdown | - +|=== + +The meaning of the RLC timers are specified in 3GPP TS 04.60. + +The countdown value specifies the RLC CV value from which the countdown +procedure is started. + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_CODING_SCHEMES]] +==== GPRS Coding Schemes + +The value part of the GPRS Coding Schemes consists of two octets +encoding the available GPRS and EDGE coding schemes. + +[options="header"] +|=== +| *bit* | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 +| byte at offset 0 | MCS9 | x | x | x | CS4 | CS3 | CS2 | CS1 +| byte at offset 1 | MCS8 | MCS7| MCS6 | MCS5 | MCS4| MCS3 | MCS2 | MCS1 +|=== + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_RLC_CFG_2]] +==== GPRS RLC Configuration 2 + +The value part of this attribute is 8 octets long and encoded as +follows: +[options="header"] +[width="60%",cols="10%,10%,70%,10%"] +|=== +| Offset | Length | Description | Unit +| 0 | 2 | Downlink TBF Extension Timer | 10ms +| 2 | 2 | Uplink TBF Extension Timer | 10ms +| 4 | 2 | Initial GPRS Coding Scheme | - +|=== + +The Initial GPRS Coding Scheme is encoded as follows: +[options="header"] +[width="40%",cols="50%,50%"] +|=== +| Value | Description +| 1 | CS 1 +| 2 | CS 2 +| 3 | CS 3 +| 4 | CS 4 +|=== + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + + +[[NM_ATT_IPACC_RLC_CFG_3]] +==== GPRS RLC Configuration 3 + +The content of this attribute contains information about the initial MCS +used for new EDGE TBFs. + +It is encoded as follows: +[options="header"] +[width="40%",cols="50%,50%"] +|=== +| Value | Description +| 1 | MCS 1 +| 2 | MCS 2 +| 3 | MCS 3 +| 4 | MCS 4 +| 5 | MCS 5 +| 6 | MCS 6 +| 7 | MCS 7 +| 8 | MCS 8 +| 9 | MCS 9 +|=== + +The content of this attribute is not used by OsmoBTS, but +simply passed to OsmoPCU connected to the PCU socket. + +=== A-bis OML Initialization / BTS bring-up + +At the time an Abis/IP BTS connects to via OML to the BSC, it is +initialized according to the procedures described in 3GPP TS 12.21 as +amended in this document. + +Each Managed Object (MO) is separately initialized. The initialization +sequence and parameters differ slightly depending on the MO involved. + +Some parts of the sequences described below are optional, such as the +Software activation. In the OsmoBTS case, the software is nod modular +and thus all MOs start with the software fully activated. Thus, no +__Software Activate Request__ is being sent by the MO to the BSC, nor +does the BSC need to initialize the __Activate Software__ procedure. + +Still, the full sequences are shown in order to explain the Abis/IP +protocol. + +Also, the initial state of the MOs at time of OML connection +initialization is not always guaranteed to be Disabled/Notinstalled. +Rather, the BSC implementation has to deal with the initial state as +reported by the MOs at time of re-connection. + +==== Site Manager MO Initialization + +.A-bis OML Initialization of Site Manager MO +["mscgen"] +---- +include::oml-mo-sitemgr.msc[] +---- + +As the Site Manager MO does not depend on other MOs, nor does it have an +Administrative state (__Locked/Unlocked__), it immediately ends up in the +__Enabled__ state. + +==== BTS MO Initialization + +.A-bis OML Initialization of BTS MO +["mscgen"] +---- +include::oml-mo-bts.msc[] +---- + +As can be seen in the BTS MO, its state is + +* Availability state __Dependency__, meaning it depends on other MOs to + be initialized before becoming enabled. +* Administrative state __Locked__, as the object is first waiting to + receive attributes in the __Locked__ state, before the __Change + Administrative State (Unlocked)__ procedure is used to request + transitioning into Unlocked state. + +==== Baseband Transceiver MO Initialization + +.A-bis OML Initialization of Baseband Transceiver MO +["mscgen"] +---- +include::oml-mo-transceiver.msc[] +---- + +There is one Baseband Transceiver MO per TRX in the BTS. For a +multi-TRX BTS, the above procedure must be repeated for each TRX. + + +==== Radio Carrier MO Initialization + +.A-bis OML Initialization of Radio Carrier MO +["mscgen"] +---- +include::oml-mo-carrier.msc[] +---- + +There is one Radio Carrier MO per TRX in the BTS. For a multi-TRX BTS, +the above procedure must be repeated for each TRX. + + +==== Channel MO Initialization + +.A-bis OML Initialization of Radio Carrier MO +["mscgen"] +---- +include::oml-mo-channel.msc[] +---- + +There are 8 Timeslots in each TRX, and correspondingly 8 Channel MOs in +every TRX. The above procedure must thus be repeated for each timeslot +in each transceiver of the BTS. + + +==== Full Initialization of entire BTS + +Some of the steps are optional, as is their detailed ordering. In +reality, the procedures for different MOs may overlap. The message +sequence charts in this document have been hand-crafted to avoid such +overlap for the sake of clarity. + +[[oml-msc-1]] +.A-bis OML BTS bring-up (1/3) +["mscgen"] +---- +include::oml-startup.msc[] +---- + +As can be seen in <<oml-msc-1>>, after the OML TCP connection is +established + +. the identity is exchanged via IPA CCM, +. the BTS sends an 'OML EVENT STATE CHANGED REPORT' for every + Managed Object +. the BTS subsequently requests the activation of its 'Site Manager' Object + which the BSC performs by the 'Activate SW' command. +. After successful activation of the software in the Site Manager, +.. the state changes to 'Enabled', and an event report is generated + accordingly +.. the BSC is notified about the SW activation in an associated report +. Finally, the BSC requests the start of the Site Manager +.. using the 'OPSTART' command, +.. which is subsequently acknowledged by the Site Manager. + +[[oml-msc-2]] +.A-bis OML BTS bring-up (2/3) +["mscgen"] +---- +include::oml-startup2.msc[] +---- + +[[oml-msc-3]] +.A-bis OML BTS bring-up (3/3) +["mscgen"] +---- +include::oml-startup3.msc[] +---- + +In <<oml-msc-2>>, we can see + +. Software Activation and associated state transitions of the BTS MO +. Setting of the BTS Attributes followed by OPSTART +. Software Activation and associated state transitions of the 'Baseband + Transceiver' MO +. Software Activation and associated state transitions of the 'Radio + Carrier' MO +. Once the 'Baseband Transceiver' MO has its software activated, the + 'Channel' MOs (one for each timeslot) indicate their state change and + software activation, too. + +In <<oml-msc-3>>, we can see + +. The 'Radio Carrier' MO Software Activation +. The Request to the 'Baseband Transceiver' MO to establish the RSL + signalling connection to the BSC. +. Subsequent OPSTART and Change of Administrative State on the 'Baseband + Transceiver' MO +. The following procedure for each of the 'Channel' MOs: +.. Setting the Channel Attributes (such as channel combination) +.. OPSTART +.. Changing the Administrative State to Unlocked +.. Subsequent State Change Event Report with the new state +. After all 'Channel' MOs are initialized, the Radio Carrier goes through + a similar procedure of +.. Setting its attributes +.. OPSTART +.. Changing its Administrative State to Unlocked +.. Subsequent State Change Event Report with the new State (Enabled/OK) +. All 'Channel' MOs now also report their state as Enabled/OK +. Finally, the BTS reports its state as Enabled/OK + diff --git a/doc/manuals/abis/rsl-startup-pri.msc b/doc/manuals/abis/rsl-startup-pri.msc new file mode 100644 index 00000000..a4798df9 --- /dev/null +++ b/doc/manuals/abis/rsl-startup-pri.msc @@ -0,0 +1,22 @@ +msc { + bts [label="TRX"], bsc [label="BSC"]; + + bts => bsc [label="TCP Connect (Port 3003, RSL)"]; + bts box bsc [label="IPA CCM Identification (Port 3003)"]; + |||; + + bts <= bsc [label="BCCH Information (SI1)"]; + bts <= bsc [label="BCCH Information (SI2)"]; + ...; + bts <= bsc [label="BCCH Information (SI3)"]; + bts <= bsc [label="BCCH Information (SI4)"]; + |||; + bts <= bsc [label="SACCH FILLING (SI5)"]; + ...; + bts <= bsc [label="SACCH FILLING (SI6)"]; + |||; + bts => bsc [label="RF Resource Indication"]; + ...; + bts => bsc [label="RF Resource Indication"]; + ...; +} diff --git a/doc/manuals/abis/rsl-startup-sec.msc b/doc/manuals/abis/rsl-startup-sec.msc new file mode 100644 index 00000000..d961412b --- /dev/null +++ b/doc/manuals/abis/rsl-startup-sec.msc @@ -0,0 +1,16 @@ +msc { + bts [label="TRX"], bsc [label="BSC"]; + + bts => bsc [label="TCP Connect (Port 3003, RSL)"]; + bts box bsc [label="IPA CCM Identification (Port 3003)"]; + |||; + + bts <= bsc [label="SACCH FILLING (SI5)"]; + ...; + bts <= bsc [label="SACCH FILLING (SI6)"]; + |||; + bts => bsc [label="RF Resource Indication"]; + ...; + bts => bsc [label="RF Resource Indication"]; + ...; +} diff --git a/doc/manuals/abis/rsl-tch-rtp.msc b/doc/manuals/abis/rsl-tch-rtp.msc new file mode 100644 index 00000000..55228b48 --- /dev/null +++ b/doc/manuals/abis/rsl-tch-rtp.msc @@ -0,0 +1,56 @@ +msc { + hscale = 2; + + ms [label="MS"], bts [label="BTS"], bsc [label="BSC"], Msc [label="MSC"], mgw [label="MGW"]; + + ms => bts [label="L1 RACH burst"]; + bts => bsc [label="RSL CHAN RQD"]; + bts <= bsc [label="RSL CHAN ACT"]; + bts => bsc [label="RSL CHAN ACT ACK"]; + bts <= bsc [label="RSL IMM ASS CMD (RR IMM ASS)"]; + ms <= bts [label="RR IMMEDIATE ASSIGN"]; + ms => bts [label="LAPDm SABM (CM SERVICE REQ)"]; + ms <= bts [label="LAPDm FIXME"]; + bts => bsc [label="RSL ESTABLISH IND (CM SERVICE REQ)"]; + bsc => Msc [label="CR (BSSAP COMPLETE L3 (CM SERVICE REQ))"]; + ...; + ms box Msc [label="MM Common Procedures (INFO, ID, AUTH, CIPH)"]; + ...; + ms => bts [label="CC SETUP"]; + bts => bsc [label="RSL DATA IND (CC SETUP)"]; + bsc => Msc [label="DT1 (DTAP (CC SETUP))"]; + ...; + ms box Msc [label="CC Signalling"]; + ...; + bsc <= Msc [label="BSSAP ASSIGNMENT CMD (TCH)"]; + bts <= bsc [label="RSL IPA CRCX", id="1"]; + bts => bsc [label="RSL IPA CRCX ACK (IP/Port @ BTS)"]; + bsc => Msc [label="FIXME"]; + Msc => mgw [label="FIXME"]; + bts <- mgw [label="Start RTP + RTCP UDP Flows"]; + + bts <= bsc [label="RSL DATA REQ (RR CHAN MOD MODIFY)"]; + ms <= bts [label="RR CHAN MOD MODIFY"]; + ms => bts [label="RR CHAN MOD MODIFY ACK"]; + bts => bsc [label="RSL DATA IND (RR CHAN MOD MODIFY ACK)"]; + |||; + bts <= bsc [label="RSL MODE MODIFY REQ"]; + bts => bsc [label="RSL MODE MODIFY ACK"]; + + Msc <= mgw [label="FIXME"]; + bsc <= Msc [label="FIXME"]; + bts <= bsc [label="RSL IPA MDCX (IP/Port @ MGW)", id="2"]; + bts => bsc [label="RSL IPA MDCX ACK"]; + + bts -> mgw [label="Start RTP + RTCP UDP Flows"]; + ms box mgw [label="Active Voice Call"]; + bts => bsc [label="RSL MEAS RES"]; + ...; + + bts <= bsc [label="RSL IPA DLCX"]; + bts => bsc [label="RSL IPA DLCX ACK"]; + bts -x mgw [label="Stop RTP + RTCP UDP Flows"]; + + bts <= bsc [label="RSL RF CHAN REL"]; + bts => bsc [label="RSL RF CHAN REL ACK"]; +} diff --git a/doc/manuals/abis/rsl.adoc b/doc/manuals/abis/rsl.adoc new file mode 100644 index 00000000..e157b25e --- /dev/null +++ b/doc/manuals/abis/rsl.adoc @@ -0,0 +1,681 @@ +== Radio Signalling Link (RSL) + +=== List of Messages + +The following tables list the RSL messages used by OsmoBTS A-bis/IP, +grouped by their level of compliance with 3GPP TS 08.58. + +==== Messages Compliant With TS 08.58 + +Specific limitations apply, see the linked sections. + +.Messages compliant with TS 08.58 +[options="header",cols="10%,20%,45%,5%,20%"] +|=== +| TS 08.58 § | This document § | Message | <-/-> | Received/Sent by OsmoBTS +5+<| *Radio link layer management messages* +| 8.3.1 | - | DATA REQUEST | <- | Received +| 8.3.2 | - | DATA INDICATION | -> | Sent +| 8.3.3 | - | ERROR INDICATION | -> | Sent +| 8.3.4 | - | ESTABLISH REQUEST | <- | Received +| 8.3.5 | - | ESTABLISH CONFIRM | -> | Sent +| 8.3.6 | - | ESTABLISH INDICATION | -> | Sent +| 8.3.7 | - | RELEASE REQUEST | <- | Received +| 8.3.8 | - | RELEASE CONFIRM | -> | Sent +| 8.3.9 | - | RELEASE INDICATION | -> | Sent +| 8.3.10 | - | UNIT DATA REQUEST | <- | Received +| 8.3.11 | - | UNIT DATA INDICATION | -> | Sent +5+<| *DEDICATED CHANNEL MANAGEMENT MESSAGES* +| 8.4.1 | - | CHANNEL ACTIVATION | <- | Received +| 8.4.2 | - | CHANNEL ACTIVATION ACKNOWLEDGE | -> | Sent +| 8.4.3 | - | CHANNEL ACTIVATION NEGATIVE ACKNOWLEDGE | -> | Sent +| 8.4.4 | - | CONNECTION FAILURE INDICATION | -> | Sent +| 8.4.5 | - | DEACTIVATE SACCH | <- | Received +| 8.4.6 | - | ENCRYPTION COMMAND | <- | Received +| 8.4.7 | - | HANDOVER DETECTION | -> | Sent +| 8.4.8 | <<MEASUREMENT_RESULT>> | MEASUREMENT RESULT | -> | Sent +| 8.4.9 | <<MODE_MODIFY>> | MODE MODIFY | <- | Received +| 8.4.10 | - | MODE MODIFY ACKNOWLEDGE | -> | Sent +| 8.4.11 | - | MODE MODIFY NEGATIVE ACKNOWLEDGE | -> | Sent +| 8.4.14 | - | RF CHANNEL RELEASE | <- | Received +| 8.4.15 | <<MS_POWER_CONTROL>> | MS POWER CONTROL | <- | Received +| 8.4.19 | - | RF CHANNEL RELEASE ACKNOWLEDGE | -> | Sent +| 8.4.20 | <<SACCH_INFO_MODIFY>> | SACCH INFO MODIFY | <- | Received +5+<| *COMMON CHANNEL MANAGEMENT MESSAGES* +| 8.5.1 | <<BCCH_INFORMATION>> | BCCH INFORMATION | <- | Received +| 8.5.2 | - | CCCH LOAD INDICATION | -> | Sent +| 8.5.3 | <<CHANNEL_REQUIRED>> | CHANNEL REQUIRED | -> | Sent +| 8.5.5 | <<PAGING_COMMAND>> | PAGING COMMAND | <- | Received +| 8.5.6 | - | IMMEDIATE ASSIGN COMMAND | <- | Received +| 8.5.8 | <<SMS_BROADCAST_COMMAND>> | SMS BROADCAST COMMAND | <- | Received +5+<| *TRX MANAGEMENT MESSAGES* +| 8.6.1 | <<RF_RESOURCE_INDICATION>> | RF RESOURCE INDICATION | -> | Sent +| 8.6.2 | <<SACCH_FILLING>> | SACCH FILLING | <- | Received +| 8.6.4 | - | ERROR REPORT | -> | Sent +|=== + +==== Messages Specific to OsmoBTS + +.Messages specific to OsmoBTS, not found in 3GPP TS 08.58 +[options="header",cols="15%,15%,45%,5%,20%"] +|=== +2+| This document § | Message | <-/-> | Received/Sent by OsmoBTS +5+<| *User Plane Transport Management* (<<user_plane_txp_mgmt>>) +.3+.| <<rsl_crcx>> | <<rsl_crcx_msg>> | RSL Create Connection (CRCX) | <- | Received + | <<rsl_crcx_msg_ack>> | RSL Create Connection (CRCX) ACK | -> | Sent + | <<rsl_crcx_msg_nack>> | RSL Create Connection (CRCX) NACK | -> | Sent +.3+.| <<rsl_mdcx>> | <<rsl_mdcx_msg>> | RSL Modify Connection (MDCX) | <- | Received + | <<rsl_mdcx_msg_ack>> | RSL Modify Connection (MDCX) ACK | -> | Sent + | <<rsl_mdcx_msg_nack>> | RSL Modify Connection (MDCX) NACK | -> | Sent +.3+.| <<rsl_dlcx>> | <<rsl_dlcx_msg>> | RSL Delete Connection (DLCX) | <- | Received + | <<rsl_dlcx_msg_ack>> | RSL Delete Connection (DLCX) ACK | -> | Sent + | <<rsl_dlcx_msg_nack>> | RSL Delete Connection (DLCX) NACK | -> | Sent + | <<rsl_dlcx_ind>> | <<rsl_dlcx_ind_msg>> | RSL Delete Connection (DLCX) Indication | -> | Sent +|=== + +==== Messages Not Implemented by OsmoBTS + +.3GPP TS 08.58 messages not implemented by OsmoBTS +[options="header",cols="10%,90%"] +|=== +| TS 08.58 § | Message +2+<| *DEDICATED CHANNEL MANAGEMENT MESSAGES* +| 8.4.12 | PHYSICAL CONTEXT REQUEST +| 8.4.13 | PHYSICAL CONTEXT CONFIRM +| 8.4.16 | BS POWER CONTROL +| 8.4.17 | PREPROCESS CONFIGURE +| 8.4.18 | PREPROCESSED MEASUREMENT RESULT +| 8.4.21 | TALKER DETECTION +| 8.4.22 | LISTENER DETECTION +| 8.4.23 | REMOTE CODEC CONFIGURATION REPORT +| 8.4.24 | ROUND TRIP DELAY REPORT +| 8.4.25 | PRE-HANDOVER NOTIFICATION +| 8.4.26 | MULTIRATE CODEC MODIFICATION REQUEST +| 8.4.27 | MULTIRATE CODEC MODIFICATION ACKNOLEWDGE +| 8.4.28 | MULTIRATE CODEC MODIFICATION NEGATIVE ACKNOWLEDGE +| 8.4.29 | MULTIRATE CODEC MODIFICATION PERFORMED +| 8.4.30 | TFO REPORT +| 8.4.31 | TFO MODIFICATION REQUEST +2+<| *COMMON CHANNEL MANAGEMENT MESSAGES* +| 8.5.4 | DELETE INDICATION +| 8.5.7 | SMS BROADCAST REQUEST +| 8.5.9 | CBCH LOAD INDICATION +| 8.5.10 | NOTIFICATION COMMAND +2+<| *TRX MANAGEMENT MESSAGES* +| 8.6.3 | OVERLOAD +2+<| *LOCATION SERVICES MESSAGES* +| 8.7.1 | LOCATION INFORMATION +|=== + + +=== Message Limitation Details + +[[MEASUREMENT_RESULT]] +==== Measurement Result + +Conforms to 3GPP TS 08.58 § 8.4.8 with this limitation: + +._Measuremet Result_ IE limitations +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.37 | MS Timing Offset | never sent by OsmoBTS +|=== + +[[MODE_MODIFY]] +==== Mode Modify + +Conforms to 3GPP TS 08.58 § 8.4.9 with these limitations: + +._Mode Modify_ IE limitations +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.45 | Main channel reference | _ignored_ +| 9.3.53 | MultiRate Control | _ignored_ +| 9.3.54 | Supported Codec Types | _ignored_ +|=== + +[[MS_POWER_CONTROL]] +==== MS Power Control + +Conforms to 3GPP TS 08.58 § 8.4.15 with these limitations: + +._MS Power Control_ IE limitations +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.31 | MS Power Parameters | _ignored_ +|=== + + +[[SACCH_INFO_MODIFY]] +==== SACCH Info Modify + +Conforms to 3GPP TS 08.58 § 8.4.20, with these exceptions: + +._SACCH Info Modify_ IE limitations +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.30 | System Info Type | See below for available types +| 9.3.23 | Starting Time | not supported, provokes an _Error Report_ response +|=== + +._System Info Type_ values that can occur on the SACCH +[options="header",width="50%",cols="20%,80%"] +|=== +| Value | Name +| 0x05 | RSL_SYSTEM_INFO_5 +| 0x06 | RSL_SYSTEM_INFO_6 +| 0x0d | RSL_SYSTEM_INFO_5bis +| 0x0e | RSL_SYSTEM_INFO_5ter +| 0x47 | RSL_EXT_MEAS_ORDER +| 0x48 | RSL_MEAS_INFO +|=== + +[[BCCH_INFORMATION]] +==== BCCH Information + +Conforms to 3GPP TS 08.58 § 8.5.1, with these limitations and extensions: + +._BCCH Information_ IE details +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.30 | System Info Type | See <<SACCH_INFO_MODIFY>> for available types +| 9.3.11 | L3 Info | This IE may be included instead of a 9.3.39 _Full BCCH Info_ IE. + The _Full BCCH Info_ takes precedence over _L3 Info_. + To stop SI transmission, both of these IEs must be omitted. +|=== + + +[[CHANNEL_REQUIRED]] +==== Channel Required + +Conforms to 3GPP TS 08.58 § 8.5.3, with these limitations: + +._Channel Required_ message IE details +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.16 | Physical Context | never sent by OsmoBTS +|=== + + +[[PAGING_COMMAND]] +==== Paging Command + +Conforms to 3GPP TS 08.58 § 8.5.5, with these limitations: + +._Paging Command_ message IE details +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.49 | eMLPP Priority | _ignored_ +|=== + +NOTE: If adding the identity to the paging queue fails, the BSC is not notified +in any way. + +[[SMS_BROADCAST_COMMAND]] +=== SMS Broadcast Command + +Conforms to 3GPP TS 08.58 § 8.5.8, with these limitations: + +._Broadcast Command_ message IE details +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.44 | SMSCB Channel Indicator | _ignored_ +|=== + + +[[RF_RESOURCE_INDICATION]] +==== RF Resource Indication + +This message does not conform to 3GPP TS 08.58 § 8.6.1, in that it omits the +_Resource Information_ IE that would contain the actual payload data, which +renders this message void. + +._RF Resource Indication_ message IE exceptions +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.21 | Resource Information | OsmoBTS omits this IE, though TS 08.58 + specifies it as mandatory. +|=== + + +[[SACCH_FILLING]] +==== SACCH Filling + +Conforms to 3GPP TS 08.58 § 8.6.2, with these limitations: + +._SACCH Filling_ message IE limitations +[options="header",cols="10%,30%,60%"] +|=== +| TS 08.58 § | IE Name | Handling +| 9.3.30 | System Info Type | See <<SACCH_INFO_MODIFY>> for available types +| 9.3.23 | Starting Time | _ignored_ +|=== + + +[[user_plane_txp_mgmt]] +=== User Plane Transport Management + +This chapter defines the A-bis/IP specific RSL procedures that are +introduced in addition to the 3GPP TS 08.58 standard procedures. + +In classic A-bis over E1, user plane traffic is carried over 16kBps +sub-slots of 64kBps E1 time-slots according to ETSI/3GPP TS 08.60. As +the E1 line is a dedicated line between BTS and BSC, no further +addressing information is required. + +In A-bis/IP as described by the present document, new RSL procedures +have been introduced in order to deal with the different properties of +the underlying IP based transport medium. + +[[rsl_crcx]] +==== RSL Create Connection (CRCX) + +This procedure is used by the BSC to request the BTS to allocate + bind +to a BTS-local UDP port for the subsequent transmission of user-plane +data via RTP. + +To do so, the BSC sends the *Create Connection (CRCX)* message. In case of +successful outcome, the BTS responds with *Create Connection (CRCX) +ACK*. In case of any error, the BTS responds with *Create Connection +(CRCX) NACK*. + +See <<rsl_crcx_msg>>, <<rsl_crcx_msg_ack>>, <<rsl_crcx_msg_nack>> + +[[rsl_mdcx]] +==== RSL Modify Connection (MDCX) + +This procedure is used by the BSC to request the BTS to modify an +already-bound BTS-local UDP port for user-plane RTP. It is used in +particular to configure the remote IP address and UDP port to which the +BTS shall send user-plane RTP traffic. This remote address is normally +either a Media Gateway (MGW) of some sort, but could also be the RTP +socket of the corresponding other leg of a mobile-to-mobile call. + +To modify a user-plane connection, the BSC sends the *Modify Connection* +message. In case of successful outcome, the BTS responds with +*Modify Connection (MDCX) ACK*. In case of any error, the BTS responds +with *Modify Connection (MDCX) NACK*. + +See <<rsl_mdcx_msg>>, <<rsl_mdcx_msg_ack>>, <<rsl_mdcx_msg_nack>> + +[[rsl_dlcx]] +==== RSL Delete Connection (DLCX) + +This procedure is used by the BSC to request the BTS to delete an +already-existing BTS-local UDP port for user-plane RTP. + +To delete a user-plane connection, the BSC sends the *Delete Connection +(DLCX)* message. In case of successful outcome, the BTS responds with +*Delete Connection (DLCX) ACK*. In case of any error, the BTS responds +with *Delete Connection (DLCX) NACK*. + +See <<rsl_dlcx_msg>>, <<rsl_dlcx_msg_ack>>, <<rsl_dlcx_msg_nack>> + +[[rsl_dlcx_ind]] +==== RSL Delete Connection (DLCX) Indication + +When a BTS-local UDP connection for user-plane RTP is automatically +released at the time of RF CHANNEL RELEASE, the BTS sends a unilateral, +non-acknowledged *RSL Delete Connection (DLCX) Indication* to the BSC. + +See <<rsl_dlcx_ind_msg>> + + +=== Message Formats and Contents + +[[rsl_crcx_msg]] +==== Create Connection (CRCX) + +This message is sent by the BSC to the BTS in order to request the +creation of a user-plane RTP connection for the specified *Channel +number*. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Destination IP Address | <<RSL_IE_IPAC_REMOTE_IP>> | O | TV | 5 +| Destination IP Port | <<RSL_IE_IPAC_REMOTE_PORT>> | O | TV | 3 +| IP Speech Mode | <<RSL_IE_IPAC_SPEECH_MODE>> | O | TV | 2 +| RTP Payload Type 2 | <<RSL_IE_IPAC_RTP_PAYLOAD2>> | O | TV | 2 +|=== + +[[rsl_crcx_msg_ack]] +==== Create Connection (CRCX) ACK + +This message is sent by the BTS to the BSC in order to acknowledge the +successful outcome of creating a user-plane RTP connection. It is sent +in response to the *Create Connection (CRCX)*. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Connection Id | <<RSL_IE_IPAC_CONN_ID>> | M | TV | 3 +| Source IP Address | <<RSL_IE_IPAC_LOCAL_IP>> | O | TV | 5 +| Source IP Port | <<RSL_IE_IPAC_LOCAL_PORT>> | O | TV | 3 +| RTP Payload Type 2 | <<RSL_IE_IPAC_RTP_PAYLOAD2>> | O | TV | 2 +|=== + +[[rsl_crcx_msg_nack]] +==== Create Connection (CRCX) NACK + +This message is sent by the BTS to the BSC in order to signal the +unsuccessful outcome of creating a user-plane RTP connection. It is +sent in response to the *Create Connection (CRCX)*. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Destination IP Address | <<RSL_IE_IPAC_REMOTE_IP>> | O | TV | 5 +| Destination IP Port | <<RSL_IE_IPAC_REMOTE_PORT>> | O | TV | 3 +| Cause | 08.58 9.3.26 | O | TLV | >= 3 +|=== + + +[[rsl_mdcx_msg]] +==== Modify Connection (MDCX) + +This message is sent by the BSC to the BTS in order to modify the +properties of a user-plane RTP connection. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Connection Id | <<RSL_IE_IPAC_CONN_ID>> | O | TV | 3 +| Destination IP Address | <<RSL_IE_IPAC_REMOTE_IP>> | O | TV | 5 +| Destination IP Port | <<RSL_IE_IPAC_REMOTE_PORT>> | O | TV | 3 +| IP Speech Mode | <<RSL_IE_IPAC_SPEECH_MODE>> | O | TV | 2 +| RTP Payload Type 2 | <<RSL_IE_IPAC_RTP_PAYLOAD2>> | O | TV | 2 +|=== + +[[rsl_mdcx_msg_ack]] +==== Modify Connection (MDCX) ACK + +This message is sent by the BTS to the BSC in order to acknowledge the +successful modification of a user-plane RTP connection. It is sent in +response to a *Modify Connection (MDCX)* + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Connection Id | <<RSL_IE_IPAC_CONN_ID>> | O | TV | 3 +| Source IP Address | <<RSL_IE_IPAC_LOCAL_IP>> | C | TV | 5 +| Source IP Port | <<RSL_IE_IPAC_LOCAL_PORT>> | C | TV | 3 +| RTP Payload Type 2 | <<RSL_IE_IPAC_RTP_PAYLOAD2>> | O | TV | 2 +|=== + +[[rsl_mdcx_msg_nack]] +==== Modify Connection (MDCX) NACK + +This message is sent by the BTS to the BSC in order to signal the +unsuccessful outcome of modifying the user-plane RTP connection for the +specified Channel number. It is sent in response to the *Modify +Connection (MDCX)*. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Cause | 08.58 9.3.26 | M | TLV | >= 3 +|=== + +[[rsl_dlcx_ind_msg]] +==== Delete Connection (DLCX) Indication + +This message is sent by the BTS in order to indicate the automatic +deletion of a BTS-local UDP connection for user-plane RTP traffic at the +time of RF Channel release. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Connection Id | <<RSL_IE_IPAC_CONN_ID>> | M | TV | 3 +| Connection Id | <<RSL_IE_IPAC_CONN_STAT>> | M | TV | 3 +| Cause | 08.58 9.3.26 | M | TLV | >= 3 +|=== + +[[rsl_dlcx_msg]] +==== Delete Connection (DLCX) + +This message is sent by the BSC to the BTS in order to request the +disconnection of a user-plane RTP connection for the specified Channel +number. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Connection Id | <<RSL_IE_IPAC_CONN_ID>> | O | TV | 3 +|=== + +[[rsl_dlcx_msg_ack]] +==== Delete Connection (DLCX) ACK + +This message is sent by the BTS in order to signal the successful +outcome of deleting the user-plane RTP connection for the specified +Channel number. It is sent in response to the *Delete Connection +(DLCX)*. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Connection Id | <<RSL_IE_IPAC_CONN_ID>> | O | TV | 3 +| Connection Statistics | <<RSL_IE_IPAC_CONN_STAT>> | C | TV | 29 +|=== + +[[rsl_dlcx_msg_nack]] +==== Delete Connection (DLCX) NACK + +This message is sent by the BTS in order to signal the unsuccessful +outcome of deleting the user-plane RTP connection for the specified +Channel number. It is sent in response to the *Delete Connection +(DLCX)*. + +[options="header"] +[cols="30%,25%,15%,15%,15%"] +|=== +| INFORMATION ELEMENT | REFERENCE | PRESENCE | FORMAT | LENGTH +| Message discriminator | 08.58 9.1 | M | V | 1 +| Message type | <<own_msg_types>> | M | V | 1 +| Channel number | 08.58 9.3.1 | M | TV | 2 +| Connection Id | <<RSL_IE_IPAC_CONN_ID>> | O | TV | 3 +| Cause | 08.58 9.3.26 | M | TLV | >= 3 +|=== + + +=== Information Element Codings + +[[own_msg_types]] +==== A-bis/IP specific RSL Message discriminators + +The following message descriminators are used in addition to those +indicated in 3GPP TS 08.58 Section 9.1: + +.OsmoBTS specific new message discriminators +[options="header",cols="10%,50%,40%"] +|=== +| Message Type | Message | This document § +| 0x70 | Create Connection (CRCX) | <<rsl_crcx_msg>> +| 0x71 | Create Connection (CRCX) ACK | <<rsl_crcx_msg_ack>> +| 0x72 | Create Connection (CRCX) NACK | <<rsl_crcx_msg_nack>> +| 0x73 | Modify Connection (MDCX) | <<rsl_mdcx_msg>> +| 0x74 | Modify Connection (MDCX) ACK | <<rsl_mdcx_msg_ack>> +| 0x75 | Modify Connection (MDCX) NACK | <<rsl_mdcx_msg_nack>> +| 0x76 | Delete Connection (DLCX) Indication | <<rsl_dlcx_ind_msg>> +| 0x77 | Delete Connection (DLCX) | <<rsl_dlcx_msg>> +| 0x78 | Delete Connection (DLCX) ACK | <<rsl_dlcx_msg_ack>> +| 0x79 | Delete Connection (DLCX) NACK | <<rsl_dlcx_msg_nack>> +|=== + +==== A-bis/IP specific RSL IEIs + +The following Information Element Identifiers (IEIs) are used in +addition to those indicated in 3GPP TS 08.58 Section 9.3.1: + +.A-bis/IP specific information elements +[options="header",cols="10%,50%,40%"] +|=== +| IEI | Name | This document § +| 0xf0 | RSL_IE_IPAC_REMOTE_IP | <<RSL_IE_IPAC_REMOTE_IP>> +| 0xf1 | RSL_IE_IPAC_REMOTE_PORT | <<RSL_IE_IPAC_REMOTE_PORT>> +| 0xf3 | RSL_IE_IPAC_LOCAL_PORT | <<RSL_IE_IPAC_LOCAL_PORT>> +| 0xf4 | RSL_IE_IPAC_SPEECH_MODE | <<RSL_IE_IPAC_SPEECH_MODE>> +| 0xf5 | RSL_IE_IPAC_LOCAL_IP | <<RSL_IE_IPAC_LOCAL_IP>> +| 0xf6 | RSL_IE_IPAC_CONN_STAT | <<RSL_IE_IPAC_CONN_STAT>> +| 0xf8 | RSL_IE_IPAC_CONN_ID | <<RSL_IE_IPAC_CONN_ID>> +| 0xfc | RSL_IE_IPAC_RTP_PAYLOAD2 | <<RSL_IE_IPAC_RTP_PAYLOAD2>> +|=== + +[[RSL_IE_IPAC_REMOTE_IP]] +==== RSL_IE_IPAC_REMOTE_IP + +This information element contains the remote (MGW side) IPv4 address in +network byte order. It is encoded as fixed-size element with one byte +IEI followed by four bytes IPv4 address. + +[[RSL_IE_IPAC_REMOTE_PORT]] +==== RSL_IE_IPAC_REMOTE_PORT + +This information element contains the remote (MGW side) UDP port in +network byte order. It is encoded as fixed-size element with one byte +IEI followed by two bytes UDP port number. + +[[RSL_IE_IPAC_LOCAL_PORT]] +==== RSL_IE_IPAC_LOCAL_PORT + +This information element contains the local (BTS side) IPv4 address in +network byte order. It is encoded as fixed-size element with one byte +IEI followed by two bytes UDP port number. + +[[RSL_IE_IPAC_SPEECH_MODE]] +==== RSL_IE_IPAC_SPEECH_MODE + +This information element encodes the speech mode. It is set according +to the voice codec used on the connection. It is encoded as a fixed-size +element of two bytes, with one byte IEI followed by one byte Speech mode +indicator. + +.A-bis/IP Speech Mode Indicator Values +[options="header",width="40%",cols="20%,80%"] +|=== +| Value | Description +| 0x00 | TCH/F with FR codec +| 0x01 | TCH/F with EFR codec +| 0x02 | TCH/F with AMR codec +| 0x03 | TCH/H with HR codec +| 0x05 | TCH/H with AMR codec +|=== + +[[RSL_IE_IPAC_LOCAL_IP]] +==== RSL_IE_IPAC_LOCAL_IP + +This information element contains the local (BTS side) IPv4 address in +network byte order. It is encoded as fixed-size element with one byte +IEI followed by four bytes IPv4 address. + +[[RSL_IE_IPAC_CONN_STAT]] +==== RSL_IE_IPAC_CONN_STAT + +This information element contains statistics about the RTP connection. + +It is encoded as 29 bytes, with the first byte as IEI and 28 bytes +fixed-length payload encoded as follows: + +.A-bis/IP Connection Statistics +[options="header",width="60%",cols="15%,15%,70%"] +|=== +| Offset | Size | Description +| 0 | 4 | Total number of RTP packets sent +| 4 | 4 | Total number of octets sent +| 8 | 4 | Total number of RTP packets received +| 12 | 4 | Total number of octets received +| 16 | 4 | Total number of lost packets in Rx direction +| 20 | 4 | Inter-arrival Jitter +| 24 | 4 | Average transmission delay +|=== + +All the above values are each encoded in network byte order. + +A detailed definition of the individual values is given in RFC 1889. + +[[RSL_IE_IPAC_CONN_ID]] +==== RSL_IE_IPAC_CONN_ID + +This IE is a TV with a value length of two bytes. The value is a 16 bit +connection ID in network byte order. + + +[[RSL_IE_IPAC_RTP_PAYLOAD2]] +==== RSL_IE_IPAC_RTP_PAYLOAD2 + +This information element contains the RTP payload identifier, which is +used in the PT (Payload Type) field of the RTP header in subsequent +transmissions of the RTP flow. + +=== A-bis RSL Initialization / BTS bring-up + +Upon receiving the 'IPA RSL CONNECT' OML message by the respective +'Baseband Transceiver' MO, the BTS proceeds with establishing a separate +TCP connection for the given TRX. + +[[rsl-msc-pri]] +.A-bis RSL BTS bring-up for primary TRX +["mscgen"] +---- +include::rsl-startup-pri.msc[] +---- + +[[rsl-msc-sec]] +.A-bis RSL BTS bring-up for secondary TRXs +["mscgen"] +---- +include::rsl-startup-sec.msc[] +---- + +As can be seen by the differences between <<rsl-msc-pri>> and +<<rsl-msc-sec>>, the initialization of the primary and secondary TRX +slightly differ. As the secondary TRX has no BCCH, it does not (need +to) receive any 'RSL BCCH INFORMATION' messages from the BSC. + diff --git a/doc/manuals/abis/rtp.adoc b/doc/manuals/abis/rtp.adoc new file mode 100644 index 00000000..e64b5c11 --- /dev/null +++ b/doc/manuals/abis/rtp.adoc @@ -0,0 +1,33 @@ +== User-Plane Traffic via RTP + +RTP (Realtime Transfer Protocol) is a protocol for streaming of audio +and video streaming data. It is specified by IETF RFC 1889. + +OsmoBTS A-bis/IP implements RTP as transport medium for circuit-switched +user-plane traffic, contrary to the E1 sub-slot based transport as +specified in 3GPP TS 08.60. + +The RTP transport endpoint parameters are configured using the RSL User +Plane Transport Management procedures described in <<user_plane_txp_mgmt>>. + +RTCP is implemented in addition to RTP, on a UDP port number of the RTP +port incremented by one. + +=== RTP Payload Formats + +The RTP payload format depends on the voice codec used on the radio +channel. The OsmoBTS is simply passing the GSM speech frames between +the Um radio interface channels and the RTP payload (and vice-versa). + +No transcoding function is implemented in the BTS! + +.RTP Payload formats +[options="header",width="60%",cols="15%,15%,70%"] +|=== +| TCH | Codec | RTP payload format specification +| TCH/F | FR | IETF RFC 3551 Section 4.5.8 +| TCH/F | EFR | IETF RFC 3551 Section 4.5.9 +| TCH/F | AMR | IETF RFC 4867 +| TCH/H | HR | IETF RFC 5993 +| TCH/H | AMR | IETF RFC 4867 +|=== diff --git a/doc/manuals/chapters/architecture.adoc b/doc/manuals/chapters/architecture.adoc new file mode 100644 index 00000000..aca5bb95 --- /dev/null +++ b/doc/manuals/chapters/architecture.adoc @@ -0,0 +1,120 @@ +== OsmoBTS software architecture + +=== OsmoBTS PHY interface abstraction + +The OsmoBTS PHY interface serves as an internal abstraction layer +between given PHY hardware (as provided by the bts_model) and the actual +logical transceivers (TRXs) of a BTS inside the OsmoBTS code base. + + +==== PHY link + +A PHY link is a physical connection / link towards a given PHY. This +might be, for example, + +* a set of file descriptors to device nodes in the /dev/ directory + (sysmobts, litecell15) +* a packet socket for sending raw Ethernet frames to an OCTPHY +* a set of UDP sockets for interacting with OsmoTRX + +Each PHY interface has a set of attribute/parameters and a list of 1 to +n PHY instances. + +PHY links are numbered 0..n globally inside OsmoBTS. + +Each PHY link is configured via the VTY using its individual top-level +vty node. Given the different bts-model / phy specific properties, the +VTY configuration options (if any) of the PHY instance differ between +BTS models. + +The PHY links and instances must be configured above the BTS/TRX nodes +in the configuration file. If the file is saved via the VTY, the code +automatically ensures this. + + +==== PHY instance + +A PHY instance is an instance of a PHY, accessed via a PHY link. + +In the case of osmo-bts-sysmo and osmo-bts-trx, there is only one +instance in every PHY link. This is due to the fact that the API inside +that PHY link does not permit for distinguishing multiple different +logical TRXs. + +Other PHY implementations like the OCTPHY however do support addressing +multiple PHY instances via a single PHY link. + +PHY instances are numbered 0..n inside each PHY link. + +Each PHY instance is configured via the VTY as a separate node beneath each +PHY link. Given the different bts-model / phy specific properties, the +VTY configuration options (if any) of the PHY instance differ between +BTS models. + + +==== Mapping PHY instances to TRXs + +Each TRX node in the VTY must use the 'phy N instance M' command in +order to specify which PHY instance is allocated to this specific TRX. + +=== Internal control flow + +==== start-up / sequencing during OsmoBTS start + +.Control flow at OsmoBTS start-up procedure +[options="header",cols="10%,35%,55%"] +|=== +| section | function | description +| bts-specific | main() | Entering main() from glibc +| common | bts_main() | initialization of talloc contexts +| common | bts_log_init() | initialization of logging +| common | handle_options() | common option parsing +| bts-specific | bts_model_handle_options() | model-specific option parsing +| common | gsm_bts_alloc() | allocation of BTS/TRX/TS data structures +| common | vty_init() | Initialziation of VTY core, libosmo-abis and osmo-bts VTY +| common | main() | Setting of scheduler RR priority (if configured) +| common | main() | Initialization of GSMTAP (if configured) +| common | bts_init() | configuration of defaults in bts/trx/s object +| bts-specific | bts_model_init | ? +| common | abis_init() | Initialization of libosmo-abis +| common | vty_read_config_file() | Reading of configuration file +| bts-specific | bts_model_phy_link_set_defaults() | Called for every PHY link created +| bts-specific | bts_model_phy_instance_set_defaults() | Called for every PHY Instance created +| common | bts_controlif_setup() | Initialization of Control Interface +| bts-specific | bts_model_ctrl_cmds_install() | Install model-specific control interface commands +| common | telnet_init() | Initialization of telnet interface +| common | pcu_sock_init() | Initializaiton of PCU socket +| common | main() | Installation of signal handlers +| common | abis_open() | Start of the A-bis connection to BSC +| common | phy_links_open() | Iterate over list of configured PHY links +| bts-specific | bts_model_phy_link_open() | Open each of the configured PHY links +| common | write_pid_file() | Generate the pid file +| common | osmo_daemonize() | Fork as daemon in background (if configured) +| common | bts_main() | Run main loop until global variable quit >= 2 +|=== + + +==== At time of OML establishment + +.Control flow at time of OML establishment +[options="header",cols="10%,35%,55%"] +|=== +| section | function | description +| bts-specific | bts_model_oml_estab() | Called by core once OML link is established +| bts-specific | bts_model_check_oml() | called each time OML sets some attributes on a MO, checks if attributes are valid +| bts-specific | bts_model_apply_oml() | called each time OML sets some attributes on a MO, stores attribute contents in data structures +| bts-specific | bts_model_opstart() | for NM_OC_BTS, NM_OC_SITE_MANAGER, NM_OC_GPRS_NSE, NM_OC_GPRS_CELL, NMO_OC_GPRS_NSVC +| bts-specific | bts_model_opstart() | for NM_OC_RADIO_CARRIER for each trx +| bts-specific | bts_model_opstart() | for NM_OC_BASEB_TRANSC for each trx +| bts-specific | bts_model_opstart() | for NM_OC_CHANNEL for each timeslot on each trx +| bts-specific | bts_model_change_power() | change transmit power for each trx (power ramp-up/ramp-down) +|=== + +==== At time of RSL connection loss + +.Control flow at time of RSL connection loss +[options="header",cols="10%,35%,55%"] +|=== +| section | function | description +| bts-specific | bts_model_abis_close() | called when either one of the RSL links or the OML link are down +|=== diff --git a/doc/manuals/chapters/bts-models.adoc b/doc/manuals/chapters/bts-models.adoc new file mode 100644 index 00000000..5a967f61 --- /dev/null +++ b/doc/manuals/chapters/bts-models.adoc @@ -0,0 +1,405 @@ +== OsmoBTS hardware support + +OsmoBTS consists of a generic part common to all BTS, and a +hardware-specific _common_ part, and a _hardware-specific_ part. The +hardware specific part is generally referred to as the _bts_model_ code. + +The common part includes the core BTS architecture as well as code for +implementing the external interfaces such Abis, control, PCU socket and +GSMTAP. + +The bts_model parts include support for driving one particular +implementation of a GSM physical layer (PHY). Such a physical layer +implementation can come in many forms. Sometimes it runs on a general +purpose CPU, sometimes on a dedicated ARM core, a dedicated DSP, a +combination of DSP and FPGA. + +Every PHY implementation offers some kind of primitives by which the PHY +can be controlled, and by which the PHY exchanges data with the higher +layers of the protocol stack in the OsmoBTS code. + +The PHY-specific primitives are encapsulated in the bts_model code, and +offered as a PHY-independent _L1SAP_ interface towards the common part of +OsmoBTS. + +In addition, each bts_model implements a set of functions that the +common part calls. Those functions are pre-fixed by bts_model_. + +Each bts_model may offer + +* model-specific VTY commands for both configuration and run-time interaction +* model-specific command line arguments +* model-specific control interface commands + +== `osmo-bts-sysmo` for sysmocom sysmoBTS + +The sysmocom sysmoBTS is a range of GSM BTSs basd around an embedded +system implementing the PHY in a combination of DSP+FPGA. The PHY is +configured by a set of primitives described by header files. Those +primitives are exchanged ove a set of message queues exposed on the +Linux-running ARM core via device nodes in `/dev/msgq/`. Internally, +the message queues map to shared memory between the Linux-running ARM +core and the DSP running the PHY implementation. + +The OsmoBTS bts_model code for the sysmoBTS can be found in the +`src/osmo-bts-sysmo` sub-directory of the OsmoBTS code base. + +`osmo-bts-sysmo` has been the primary target platform for +OsmoBTS for many years and is thus the most feature-complete and mature +platform supported by OsmoBTS at this point. + +The sysmoBTS PHY supports a direct PHY interface to OsmoPCU, reducing +the latency and amount of primitives that OsmoBTS would otherwise need +to pass through from the PHY message queues to the PCU socket and +vice-versa. + + +=== `osmo-bts-sysmo` specific command line arguments + +*--dsp-trace 'DSPMASK'*:: + Set the DSP trace flags (a single hexadecimal 32bit value). + This has been deprecated by VTY based commands, see + <<osmo-bts-sysmo-dsp-trace>> for further information. +*--pcu-direct*:: + Indicate that an external PCU (e.g. OsmoPCU) will directly + open the DSP messge queues to the PHY / PH-SAP, and only MPH + primitives are passed via OsmoBTS. + + +=== `osmo-bts-sysmo` specific VTY commands + +For a auto-generated complete syntax reference of the VTY commands, +please see the associated _OsmoBTS VTY reference manual_ +<<vty-ref-osmobts>>. The section +below only lists the most important commands. + +==== at the 'SHOW' node + +===== `show trx 0 clock-source` + +Display the currently active clock source configuration for the TRX + +[[osmo-bts-sysmo-dsp-trace]] +===== `show trx 0 dsp-trace-flags` + +Show the currently active DSP trace flags for the TRX + +===== `trx 0 dsp-trace-flag` + +Use this command to enable/disable/configure the DSP tracing flags that +define what debug messages will appear on `/dev/rtfifo/dsp_trace`. + +==== at the 'ENABLE' node + +===== `trx 0 tx-power <-110-100>` + +Change the current TRX transmit power to the given value in dBm. + +===== `trx 0 rf-clock-info reset` + +Part of the clock calibration procedure: +Reset the clock correction value. + +===== `trx 0 rf-clock-info correct` + +Part of the clock calibration procedure: +Apply the current measured correction value between the reference clock +and the local clock. + +==== at the 'PHY instance' node + +==== `clock-calibration eeprom` + +Obtain clock calibration value from EEPROM. + +==== `clock-calibration default` + +Use hardware default clock calibration value. + +==== `clock-calibration <-4095-4095>` + +Use specified clock calibration value (not EEPROM/default). + +==== `clock-source (tcxo|ocxo|ext|gps)` + +Specify the clock source for the PHY: + +tcxo:: + Use the TCXO. This is the default on sysmoBTS 2050. +ocxo:: + Use the OCXO (only valid on units equipped with OCXO). This is + the default on all sysmoBTS 1002/1020/1100 and SOB-BTS. +ext:: + Use the external clock input. +gps:: + Use the clock derived from GPS. You shouldn't use this clock + directly, but rather use the TCXO and regularly re-calibrate + against GPS. + +==== `trx-calibration-path PATH` + +Use calibration files from the given 'PATH', rather tan calibration +values from the EEPROM. + +=== `osmo-bts-sysmo` specific control interface commands + +==== trx.0.clock-info + +Obtain information on the current clock status: + +---- +bsc_control.py -d localhost -p 4238 -g trx.0.clock-info +Got message: GET_REPLY 1 trx.0.clock-info -100,ocxo,0,0,gps +---- + +which is to be interpreted as: + +* current clock correction value is -100 ppb +* current clock source is OCXO +* deviation between clock source and calibration source is 0 ppb +* resolution of clock error measurement is 0 ppt (0 means no result yet) +* current calibration source is GPS + +When this attribute is set, any value passed on is discarded, but the clock +calibration process is re-started. + +==== trx.0.clock-correction + +This attribute can get and set the current clock correction value: + +---- +bsc_control.py -d localhost -p 4238 -g trx.0.clock-correction +Got message: GET_REPLY 1 trx.0.clock-correction -100 +---- + +---- +bsc_control.py -d localhost -p 4238 -s trx.0.clock-correction -- -99 +Got message: SET_REPLY 1 trx.0.clock-correction success +---- + + +== `osmo-bts-trx` for OsmoTRX + +OsmoTRX is a C-language implementation of the GSM radio modem, +originally developed as the 'Transceiver' part of OpenBTS. This radio +modem offers an interface based on top of UDP streams. + +The OsmoBTS bts_model code for OsmoTRX is called +`osmo-bts-trx`. It implements the UDP stream interface of +OsmoTRX, so both parts can be used together to implement a complete GSM +BTS based on general-purpose computing SDR. + +As OsmoTRX is general-purpose software running on top of Linux, it is +thus not tied to any specific physical hardware. At the time of this +writing, OsmoTRX supports a variety of Ettus USRP SDRs via the UHD +driver, as well as the Fairwaves UmTRX and derived products. + +OsmoTRX is not a complete GSM PHY but 'just' the radio modem. This +means that all of the Layer 1 functionality such as scheduling, +convolutional coding, etc. is actually also implemented inside OsmoBTS. + +As such, the boundary between OsmoTRX and `osmo-bts-trx` is at +a much lower interface, which is an internal interface of other more +traditional GSM PHY implementations. + +Besides OsmoTRX, there are also other implementations (both Free +Software and proprietary) that implement the same UDP stream based radio +modem interface. + + +=== `osmo-bts-trx` specific VTY commands + +For a auto-generated complete syntax reference of the VTY commands, +pleas see the associated _OsmoBTS VTY reference manual_ +<<vty-ref-osmobts>>. The section below only lists the most important +commands. + +==== at the 'SHOW' node + +===== `show transceivers` + +Display information about configured/connected OsmoTRX transceivers in +human-readable format to current VTY session. + +==== at the 'PHY' configuration node + +===== `osmotrx ip HOST` + +Set the IP addess of the OsmoTRX transceiver to which we should connect +to. + +===== `osmotrx base-port (local|remote) <0-65535>` + +Configure the base UDP port for the OsmoTRX interface for either the +local (OsmoBTS) or remote (OsmoTRX) side of the UDP flows. + +===== `osmotrx fn-advance <0-30>` + +Set the number of frames to be transmitted to transceiver in advance of +current GSM frame number. + +===== `osmotrx rts-advance <0-30>` + +Set the number of frames to be requested from PCU in advance of current +frame number. Do not change this unless you have a good reason! + +===== `osmotrx rx-gain <0-50>` + +Set the receiver gain (configured in the hardware) in dB. + +===== `osmotrx tx-attenuation <0-50>` + +Set the transmitter attenuation (configured in the hardware) in dB. + +===== `osmotrx tx-attenuation oml` + +Use the Value in the A-bis OML Attribute `MAX_POWER_REDUCTION` as +transmitter attenuation. + +==== at the 'PHY Instance' configuration node + +===== `slotmask (1|0) (1|0) (1|0) (1|0) (1|0) (1|0) (1|0) (1|0)` + +Configure which timeslots should be active on this TRX. Normally all +timeslots are enabled, unless you are running on a cpu-constrained +deeply embedded system. + +===== `osmotrx maxdly <0-31>` + +Set the maximum delay for received symbols (in number of GSM symbols). + + +== `osmo-bts-octphy` for Octasic OCTPHY-2G + +The Octasic OCTPHY-2G is a GSM PHY implementation inside an Octasic +proprietary 24-core DSP called OCTDSP. + +This DSP has a built-in Gigabit Ethernet interface, over which it +exchanges PHY-layer primitives in raw Ethernet frames with the upper +layers running on another CPU attached to the same Ethernet. Those +primitives are described in a set of C-language header files. + +OsmoBTS implements the raw Ethernet frame based primitives as well as +the associated transport protocol (OKTPKT/OCTVC1) in the +`osmo-btso-octphy` bts_model code. + +You can run the `osmo-bts-octphy` on any system connected to the same +Ethernet as the OCTDSP running the OCTPHY. This can be either an +embedded ARM or x86 SoM part of the OCTBTS hardware, or it can be any +other Linux system attached via an Ethernet switch. + +Each OCTDSP running OCTSDR-2G offers a set of primitives part of a +OCTPKT session, which is mapped to an OsmoBTS PHY link. Depending on +the OCTSDR-2G software version, you may create multiple software TRX by +creating multiple OsmoBTS PHY instances inside that PHY link. + +Multiple DSPs may exsist in one circuit board, then each of the DSPs is +interfaced by one OsmoBTS PHY link, and each of them may have one or +more OsmoBTS PHY instances creating a Multi-TRX configuration. + + +== `osmo-bts-litecell15` for Nutaq/Nuran LiteCell 1.5 + +The Nutaq/Nuran LiteCell 1.5 implements a dual-transceiver GSM BTS based +on a mixed ARM/DSP/FPGA architecture. The PHY layer is implemented on +DSP/FPGA and similar to that of the sysmoBTS: It exchanges primitives +described in a set of C-language header files over message queues +between the ARM and the DSP. + +This interface is implemented in the `osmo-bts-litecell15` bts_model of +OsmoBTS. You would run `osmo-bts-litecell15` on the ARM/Linux processor +of the Litecell 1.5. + +The two transceivers of the Litecell 1.5 each have their own set of DSP +message queues. Each set of message queues is wrapped into one OsmoBTS +PHY link, offering one OsmoBTS PHY instance. + +The Litecell 1.5 PHY supports a direct PHY interface to OsmoPCU, +reducing the latency and amount of primitives that OsmoBTS would +otherwise need to pass through from the PHY message queues to the PCU +socket and vice-versa. + +=== `osmo-bts-trx` specific VTY commands + +For a auto-generated complete syntax reference of the VTY commands, +please see the associated _OsmoBTS VTY reference manual_ +<<vty-ref-osmobts>>. The section below only lists the most important +commands. + +==== at the 'SHOW' node + +===== `show phy <0-255> system-information` + +Show information about the hardware platform, DSP and OCTPHY-2G software +version. + +===== `show phy <0-255> rf-port-stats <0-1>` + +Show information about the RF port interfaces. + +===== `show phy <0-255> clk-sync-stats` + +Show information about the clock synchronization manager. + +==== at the 'PHY' configuration node + +===== `octphy hw-addr HWADDR` + +Specify the Ethernet hardware address (mac address) of the DSP running +the OCTPHY-2G software for this PHY link. + +===== `octphy net-device NAME` + +Specify the Ethernet network device (like `eth0`) through which the DSP +can be reached from OsmoBTS. + +===== `octphy rf-port-index <0-255>` + +Specify which RF port should be used for this PHY link. + +===== `octphy rx-gain <0-73>` + +Configure the receiver gain in dB. + +===== `octphy tx-attenuation <0-359>` + +Configure the transmitter attenuation in quarter-dB + + + + +== `osmo-bts-virtual` for Virtual Um Interface + +This is a special BTS model used for research, simulation and testing. +Rather than communicating over a wireless RF interface, the GSM Um +messages are encapsulated over GSMTAP/UDP/IP. + +At the time of writing, this functionality is not fully completed. It +is the idea to adopt the OsmocomBB MS-side GSM implementation to +interface with this virtual Um interface, so that many instances of +virtual MS can connect to some instances of OsmoBTS, testing MS, BTS, +BSC and core network functionality. + +=== `osmo-bts-trx` specific VTY commands + +For a auto-generated complete syntax reference of the VTY commands, +please see the associated _OsmoBTS VTY reference manual_ +<<vty-ref-osmobts>>. The section below only lists the most important +commands. + +==== at the 'PHY' config node + +===== `virtual-um net-device NETDEV` + +Configure the network device used for sending/receiving the virtual Um +interface messages (e.g. `eth0`). + +===== `virtual-um udp-port <0-65535>` + +Configure the UDP port used for sending/receiving the virtual Um +interface messages (default: GSMTAP 2775). + +===== `virtual-um multicast-group GROUP` + +Configure the IP multicast group used for sending/receiving the virtual +Um interface messages. diff --git a/doc/manuals/chapters/configuration.adoc b/doc/manuals/chapters/configuration.adoc new file mode 100644 index 00000000..a2d06249 --- /dev/null +++ b/doc/manuals/chapters/configuration.adoc @@ -0,0 +1,154 @@ +== BTS Configuration + +The role of the BTS is to handle the GSM radio interface. When the BTS +application is starting, the A-bis OML connection is established towards +the BSC. Almost all BTS configuration (such as ARFCN, channel +configuration, transmit power, etc.) will be sent from the BSC to the +BTS via OML messages. After OML start-up has competed, the BSC will +instruct the BTS to establish the RSL connections. + +Given that most configuration is downloaded from the BSC into the BTS at +start-up time, only some very basic settings have to be made in the +OsmoBTS software. + + +=== Command Line Options + +Ths OsmoBTS executables (`osmo-bts-sysmo`, `osmo-bts-trx`, +`osmo-bts-octphy`, `osmo-bts-litecell15`, ...) share the following +generic command line options: + +==== SYNOPSIS +*osmo-bts-sysmo* [-h|-V] [-d 'DBGMASK'] [-D] [-c 'CONFIGFILE' ] [-s] [-T] [-e 'LOGLEVEL'] [-r 'PRIO'] [-i 'GSMTAP-IP'] [-t <1-255>] + +==== OPTIONS +*-h, --help*:: + Print a short help message about the supported options +*-V, --version*:: + Print the compile-time version number of the OsmoBTS program +*-d, --debug 'DBGMASK','DBGLEVELS'*:: + Set the log subsystems and levels for logging to stderr. This + has mostly been superseded by VTY-based logging configuration, + see <<logging>> for further information. +*-D, --daemonize*:: + Fork the process as a daemon into background. +*-c, --config-file 'CONFIGFILE'*:: + Specify the file and path name of the configuration file to be + used. If none is specified, use `osmo-bts.cfg` in the current + working directory. +*-s, --disable-color*:: + Disable colors for logging to stderr. This has mostly been + deprecated by VTY based logging configuration, see <<logging>> + for further information. +*-T, --timestamp*:: + Enable time-stamping of log messages to stderr. This has mostly + been deprecated by VTY based logging configuration, see + <<logging>> for further information. +*-e, --log-level 'LOGLEVEL'*:: + Set the global log level for logging to stderr. This has mostly + been deprecated by VTY based logging configuration, see + <<logging>> for further information. +*-r, --realtime 'PRIO'*:: + Enable use of the Linux kernel realtime priority scheduler with + the specified priority. + It is recommended you use this option on low-performance + embedded systems or systems that encounter high non-GSM/GPRS + load. +*-i, --gsmtap-ip 'GSMTAP-IP'*:: + Specify the destination IP address for GSMTAP messages. +*-t, --trx-num <1-255>*:: + Specify the number of TRX supported by this BTS. + +There may be additional, hardware specific command line options by the +different bts_model implementations. + + +=== Configuration using the VTY + +Most configuration as well as run-time monitoring and system +introspection is implemented using a command-line based interface +called _VTY_. A full reference syntax of all existing VTY command is +available as a separate document. + +See <<vty>> for further information on the VTY. + + +==== Required BTS/TRX configuration + +There are some settings that have to be configured locally in the +sysmoBTS, as they cannot be set remotely from the BSC. Those +settings are stored in the OsmoBTS configuration file, which commonly +is stored in `/etc/osmocom/osmo-bts.cfg`. + +.Example Minimal configuration file +---- +! +! OsmoBTS (0.0.1.100-0455) configuration saved from vty +!! +! +phy 0 <1> + instance 0 <2> +bts 0 <3> + band DCS1800 + ipa unit-id 1801 0 <4> + oml remote-ip 192.168.100.11 <5> + trx 0 <6> + phy 0 instance 0 <7> +---- +<1> You must configure at least one PHY link by means of the PHY node +<2> You must configure at least one PHY instance in the PHY link +<3> There is always exactly one BTS (`bts 0`) configured in OsmoBTS +<4> The `ipa unit-id` is what is used to identify this BTS to the BSC +<6> The OML Remote IP is the IP address of the BSC, to which the BTS shall connect to. +<6> There must be at least one trx (`trx 0`) in each BTS +<7> Every TRX must be mapped to a specific PHY instance this way + +For a full reference of all available VTY configuration parameters, +please refer to the OsmoBTS VTY Reference document. + +[[gsmtap]] +==== Configuring GSMTAP tracing + +In addition to being able to obtain pcap protocol traces of the A-bis +communication and the text-based logging from the OsmoBTS +software, there is also the capability of tracing all communication on +the radio interface. To do so, OsmoBTS can encapsulate +MAC blocks (23byte messages at the L2-L1 interface) into _GSMTAP_ and send +them via UDP/IP. At that point, they can be captured with utilities like +*tcpdump* or *tshark* for further analysis by the *wireshark* protocol +analyzer. + +In order to activate this feature, you first need to make sure to start +OsmoBTS using the `-i` or `--gsmtap-ip` command line option, specifying +the destination IP address for the GSMTAP messages. In most cases, +using 127.0.0.1 for passing the messages over the loopback (`lo`) device +will be sufficient. + +OsmoBTS can selectively trace such messages by their L1 SAPI, for both +Rx and Tx. For a complete list of L1 SAPI values, please refer to the +_OsmoBTS VTY reference manual_ <<vty-ref-osmobts>>. + +For example, to enable GSMTAP tracing for messages on all SDCCH +channels, you can use the gsmtap-sapi sdcch command at the CONFIG TRX +node of the OsmoBTS VTY. + +.Example: Enabling GSMTAP for SDCCH +---- +OsmoBTS> enable +OsmoBTS# configure terminal +OsmoBTS(config)# bts +OsmoBTS(bts)# trx 0 +OsmoBTS(trx)# gsmtap-sapi sdcch +OsmoBTS(trx)# write <1> +---- +<1> the `write` command will make the configuration persistent in the +configuration file. This is not required if you wish to enable GSMTAP +only in the current session of OsmoBTS. + +De-activation can be performed similarly by using the `no gsmtap-sapi +sdcch` command at the `trx` node of the OsmoBTS VTY. + +From the moment they are enabled via VTY, GSMTAP messages will be +generated and sent in UDP encapsulation to the IANA-registered UDP port +for GSMTAP (4729) at the IP address specified in the command line +argument. diff --git a/doc/manuals/chapters/interfaces.adoc b/doc/manuals/chapters/interfaces.adoc new file mode 100644 index 00000000..f5bf1b20 --- /dev/null +++ b/doc/manuals/chapters/interfaces.adoc @@ -0,0 +1,130 @@ +== OsmoBTS Interfaces + +OsmoBTS offers a set of interfaces to interact with external entities: + +* A-bis/IP interface to talk to the BSC +* bts_model specific PHY interface +* VTY interface +* Osmocom control interface +* GSMTAP interface +* PCU interface + + +=== OsmoBTS Abis/IP Interface + +OsmoBTS implements the GSM A-bis interface as described in the relevant +3GPP specifications: + +* A-bis RSL according to 3GPP TS 08.58 +* A-bis OML according to 3GPP TS 12.21 + +As the 3GPP specified A-bis only over E1 interfaces and not over IP, +significant enhancements and modifications have been performed as opposed +to the 3GPP specifications. Nevertheless, the implementation tries to +stay as close a possible to the 3GPP specifications. + +Please see the _OsmoBTS Abis Protocol Specification_ +<<osmobts-abis-spec>> for more information on this subject. + + +=== bts_model specific PHY interface + +This interface is specific to the bts_model that OsmoBTS was compiled +for. It can take any form as required by the respective hardware. + +Please see the PHY documentation of your respective BTS hardware for more +details. + + +=== OsmoBTS VTY Interface + +See <<vty>> for further information. + + +=== OsmoBTS Control Interface + +The general structure of the Omsocom control interface is described in +<<common-control-if>>. + +The number of control interface commands/attributes is currently quite +limited and largely depends on the bts_model used. + +==== trx.N.thermal-attenuation + +The idea of this paramter is to attenuate the system output power as part of +thermal management. In some cases the PA might be passing a critical level, +so an external control process can use this attribute to reduce the system +output power. + +Please note that all values in the context of transmit power calculation +are integers in milli-dB (1/10000 bel), so the below example is setting +the attenuation at 3 dB: + +---- +bsc_control.py -d localhost -p 4238 -s trx.0.thermal-attenuation 3000 +Got message: SET_REPLY 1 trx.0.thermal-attenuation 3000 +---- + +---- +bsc_control.py -d localhost -p 4238 -g trx.0.thermal-attenuation +Got message: GET_REPLY 1 trx.0.thermal-attenuation 3000 +---- + + + +=== OsmoBTS GSMTAP Interface + +GSMTAP is a standard created by Osmocom to UDP-encapsulate GSM protocol +messages normally communicated over non-IP interfaces for the primary +purpose of protocol analysis in the wireshark dissector. + +The initial purpose was to encapsulate GSM Um frames including some +meta-data like ARFCN and GSM frame number into something that can be +parsed and dispatched within the wireshark dissector. + +This interface has since been extended to many other +GSM/GPRS/UMTS interfaces and protocols, and even to TETRA and GMR. + +In OsmoBTS, it is possible to export both uplink and downlink Um +messages via GSMTAP. There is a set of VTY configuration options to +specify for which logical channels of the Um interface GSMTAP messages +shall be emitted, and to which destination IP address they shall be +sent. + +Using GSMTAP it is possible to place a virtual tap at the air interface +between BTS and MS, without going through the trouble of setting up an +actual radio receiver at the same frequencies. Also, GSMTAP export is +performed before the Um air-interface encryption (A5) is performed, so +all frames are always in plain text. + +Please refer to <<gsmtap>> for more information on how to configure and +use this interface. + + +=== OsmoBTS PCU Socket Interface + +In order to assist the provisioning of GPRS services over the same radio +interface as circuit-switched GSM, OsmoBTS exposes a Unix domain socket +based interface towards OsmoPCU. + +OsmoPCU is the Osmocom implementation of the GPRS Packet Control Unit +(PCU), which is co-located with the BTS in the Osmocom implementation. +Contrary to that, many classic E1-based implementations of the GSM RAN +co-locate the PCU with the BSC. However, the GSM specifications keep +the location up to the implementor. + +The PCU socket interface serves the following purposes: + +* to pass PCU relevant configuration from BTS to PCU +* to forward paging requests from BTS to PCU +* to forward RACH Requests from BTS to PCU + +Depending on your bts_model, the PCU may also be passing actual +PH-DATA.request / PH-DATA.indication / PH-RTS.indication primitives for +the PDCH. This is considered sub-optimal, and some BTS models offer a +direct interface by which the PCU can exchange those primitives directly +with the PHY. + +The default PCU socket interface name is `/tmp/pcu_sock`, but this can +be overridden by the @pcu-socket@ VTY command in the BTS configuration +VTY node. diff --git a/doc/manuals/chapters/overview.adoc b/doc/manuals/chapters/overview.adoc new file mode 100644 index 00000000..6b6b8284 --- /dev/null +++ b/doc/manuals/chapters/overview.adoc @@ -0,0 +1,105 @@ +== Overview + +=== About this manual + +This manual should help you getting started with the OsmoBTS software. +It will cover aspects of configuring and running OsmoBTS as well as some +introduction about its internal architecture and external interfaces. + +=== About OsmoBTS + +OsmoBTS is an implementation of a GSM BTS (Base Transceiver Station). A +BTS serves as the interface between the Um radio interface towards +phones and the wired Abis interface towards the BSC (Base Station +Controller). It also implements the network side of the Layer 2 of the +Um radio interface: The LAPDm protocol. + +OsmoBTS is licensed as Free and Open Source Software (FOSS) under _GNU +AGPLv3_ <<gnu-agplv3>>. It is developed as one GSM network +infrastructure component part of the overall Osmocom project. + +As perhaps the first implementation of a GSM BTS ever in the industry, +OsmoBTS is implemented in a vendor-independent way and supports a large +variety of transceiver hardware and physical layer implementations from +many vendors. + +=== Credits + +OsmoBTS was originally developed in 2011 by Andreas Eversberg and Harald +Welte. It has since been maintained by Harald Welte and Holger Freyther +at sysmocom. + +=== OsmoBTS in the Osmocom GSM network architecture + +OsmoBTS can be used in combination with the various other GSM network +elements developed under the umbrella of the Osmocom project. + +Typical configurations either use OsmoBTS with OsmoBSC, or with +OsmoNITB, as can be seen in the following figures. + +[[fig-gsm-classic]] +.Classic GSM archtiecture using OsmoBTS with OsmoBTS components +[graphviz] +---- +digraph G { + rankdir=LR; + MS0 [label="MS"] + MS1 [label="MS"] + MS2 [label="MS"] + MS3 [label="MS"] + BTS0 [label="OsmoBTS"] + BTS1 [label="OsmoBTS"] + BSC [label="OsmoBSC"] + MSC [label="MSC/VLR"] + HLR [label="HLR/AUC"] + MS0->BTS0 [label="Um"] + MS1->BTS0 [label="Um"] + MS2->BTS1 [label="Um"] + MS3->BTS1 [label="Um"] + BTS0->BSC [label="Abis"] + BTS1->BSC [label="Abis"] + BSC->MSC [label="A"] + MSC->HLR [label="C"] + MSC->EIR [label="F"] + MSC->SMSC +} +---- + + +[[fig-gsm-nitb]] +.GSM architecture using OsmoBTS + OsmoNITB +[graphviz] +---- +digraph G { + rankdir=LR; + MS0 [label="MS"] + MS1 [label="MS"] + MS2 [label="MS"] + MS3 [label="MS"] + BTS0 [label="OsmoBTS"] + BTS1 [label="OsmoBTS"] + MS0->BTS0 [label="Um"] + MS1->BTS0 [label="Um"] + MS2->BTS1 [label="Um"] + MS3->BTS1 [label="Um"] + BTS0->BSC [label="Abis"] + BTS1->BSC [label="Abis"] + subgraph cluster_nitb { + label = "OsmoNITB"; + BSC + MSC [label="MSC/VLR"] + HLR [label="HLR/AUC"] + BSC->MSC [label="A"] + MSC->HLR [label="C"] + MSC->EIR [label="F"] + MSC->SMSC; + } +} +---- + +If intended by the user, it is of course also possible to implement an +OsmoBTS-compatible Abis-over-IP interface in any third party BSC. The +Abis/IP interface and its protocol are documented in the _OsmoBTS +Abis Protocol Specification_ <<osmobts-abis-spec>>. However, be advised +that such a configuration is currently not officially supported by +Osmocom. diff --git a/doc/manuals/osmobts-abis-docinfo.xml b/doc/manuals/osmobts-abis-docinfo.xml new file mode 100644 index 00000000..6cbc28fa --- /dev/null +++ b/doc/manuals/osmobts-abis-docinfo.xml @@ -0,0 +1,68 @@ +<revhistory> + <revision> + <revnumber>1</revnumber> + <date>December 2015</date> + <authorinitials>NJH, HW</authorinitials> + <revremark> + Initial version, reflecting OsmoBTS master branch as on 2015-Dec-7 + (commit e28a20a2d9d049cd6312e218a7646593bbc43431). + </revremark> + </revision> + <revision> + <revnumber>2</revnumber> + <date>February 2016</date> + <authorinitials>HW</authorinitials> + <revremark> + Updated version with Message Sequence Chart of OML and RSL bring-up. + </revremark> + </revision> + <revision> + <revnumber>2.1</revnumber> + <date>February 2016</date> + <authorinitials>HW</authorinitials> + <revremark> + Fix A-bis OML/RSL port number swap in message seqeuence charts. + </revremark> + </revision> +</revhistory> + +<authorgroup> + <author> + <firstname>Neels</firstname> + <surname>Hofmayr</surname> + <email>nhofmayr@sysmocom.de</email> + <authorinitials>NJH</authorinitials> + <affiliation> + <shortaffil>sysmocom</shortaffil> + <orgname>sysmocom - s.f.m.c. GmbH</orgname> + <jobtitle>Senior Software Developer</jobtitle> + </affiliation> + </author> + <author> + <firstname>Harald</firstname> + <surname>Welte</surname> + <email>hwelte@sysmocom.de</email> + <authorinitials>HW</authorinitials> + <affiliation> + <shortaffil>sysmocom</shortaffil> + <orgname>sysmocom - s.f.m.c. GmbH</orgname> + <jobtitle>Managing Director</jobtitle> + </affiliation> + </author> +</authorgroup> + +<copyright> + <year>2015-2016</year> + <holder>sysmocom - s.f.m.c. GmbH</holder> +</copyright> + +<legalnotice> + <para> + Permission is granted to copy, distribute and/or modify this + document under the terms of the GNU Free Documentation License, + Version 1.3 or any later version published by the Free Software + Foundation; with no Invariant Sections, no Front-Cover Texts, + and no Back-Cover Texts. A copy of the license is included in + the section entitled "GNU Free Documentation License". + </para> +</legalnotice> diff --git a/doc/manuals/osmobts-abis.adoc b/doc/manuals/osmobts-abis.adoc new file mode 100644 index 00000000..6b4f0dac --- /dev/null +++ b/doc/manuals/osmobts-abis.adoc @@ -0,0 +1,90 @@ +OsmoBTS Abis Protocol Specification +=================================== +Neels Hofmeyr <nhofmeyr@sysmocom.de> + +== Introduction + +This document describes the A-bis interface of *OsmoBTS*. Based on 3GPP TS +12.21 and 08.58, this document indicates which of the 3GPP specified A-bis +messages and IEs are implemented according to 3GPP specifications, which of +these are not or not fully implemented, as well as OsmoBTS-specific extensions +to the A-bis interface not specified by 3GPP. + +Extensions to the A-bis interface specific to OsmoBTS are detailed in this +document. For details on the messages and IEs that comply with abovementioned +3GPP specifications, please refer to those documents. + +.3GPP document versions referred to by this document +[cols="20%,80%"] +|=== +|3GPP TS 08.56 | version 8.0.1 Release 1999 +|3GPP TS 08.58 | version 8.6.0 Release 1999 +|3GPP TS 08.60 | version 8.2.1 Release 1999 +|3GPP TS 12.21 | version 8.0.0 Release 1999 +|=== + +.IETF documents referred to by his document +[cols="20%,80%"] +|=== +|IETF RFC 768 | User Datagram Protocol +|IETF RFC 791 | Internet Protocol +|IETF RFC 793 | Transmission Control Protocol +|IETF RFC 1889 | RTP: A Transport Protocol for Real-Time Applications +|IETF RFC 3551 | RTP Profle for Audio and Video Conferences with Minimal Control +|IETF RFC 4867 | RTP Payload Format and Files Storage Format for the Adaptive Multi-Rate (AMR) and Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs +|IETF RFC 5993 | RTP Payload Format for Global Systems for Mobile Communications Half Rate (GSM-HR) +|=== + +== Overview + +The OsmoBTS A-bis interface consists of traffic management messages (RSL, Radio +Signalling Link) and network management messages (OML, Operation & Maintenance +Link), encapsulated in an IPA multiplex. + +OML and RSL each use a separate TCP connection. + +.TCP port numbers used by OsmoBTS Abis/IP +[options="header",width="50%",cols="35%,65%"] +|=== +|TCP Port Number|Usage +|3002|A-bis OML (inside IPA multiplex) +|3003|A-bis RSL (inside IPA multiplex) +|=== + +Both TCP connections for OML and RSL are established in the BTS -> BSC +direction, i.e. the BTS is running as a TCP client, while the BSC is +running as a TCP server. + +The BTS first establishes the TCP connection for OML. Via OML, the BSC +instructs the BTS to which IP address the RSL connection shall be +established. + +.Overview of A-bis connection establishment +["mscgen"] +---- +include::abis/abis-startup.msc[] +---- + +=== Identities + +The BTS is locally configured (via administrative means, out of band of +this specification) to have a Unit ID. The Unit ID consists of three +parts: + +* The Site Number +* The BTS number at the site +* The TRX number within the BTS + +include::abis/ipa.adoc[] + +include::abis/oml.adoc[] + +include::abis/rsl.adoc[] + +include::abis/rtp.adoc[] + +include::../common/chapters/port_numbers.adoc[] + +include::../common/chapters/glossary.adoc[] + +include::../common/chapters/gfdl.adoc[] diff --git a/doc/manuals/osmobts-usermanual-docinfo.xml b/doc/manuals/osmobts-usermanual-docinfo.xml new file mode 100644 index 00000000..aa3285f1 --- /dev/null +++ b/doc/manuals/osmobts-usermanual-docinfo.xml @@ -0,0 +1,42 @@ +<revhistory> + <revision> + <revnumber>1</revnumber> + <date>January 2016</date> + <authorinitials>HW</authorinitials> + <revremark> + Initial version, reflecting OsmoBTS master branch as on FIXME + (commit FIXME). + </revremark> + </revision> +</revhistory> + +<authorgroup> + <author> + <firstname>Harald</firstname> + <surname>Welte</surname> + <email>hwelte@sysmocom.de</email> + <authorinitials>HW</authorinitials> + <affiliation> + <shortaffil>sysmocom</shortaffil> + <orgname>sysmocom - s.f.m.c. GmbH</orgname> + <jobtitle>Managing Director</jobtitle> + </affiliation> + </author> +</authorgroup> + +<copyright> + <year>2016</year> + <holder>sysmocom - s.f.m.c. GmbH</holder> +</copyright> + +<legalnotice> + <para> + Permission is granted to copy, distribute and/or modify this + document under the terms of the GNU Free Documentation License, + Version 1.3 or any later version published by the Free Software + Foundation; with the Invariant Sections being just 'Foreword', + 'Acknowledgements' and 'Preface', with no Front-Cover Texts, + and no Back-Cover Texts. A copy of the license is included in + the section entitled "GNU Free Documentation License". + </para> +</legalnotice> diff --git a/doc/manuals/osmobts-usermanual.adoc b/doc/manuals/osmobts-usermanual.adoc new file mode 100644 index 00000000..914fdbe2 --- /dev/null +++ b/doc/manuals/osmobts-usermanual.adoc @@ -0,0 +1,32 @@ +OsmoBTS User Manual +=================== +Harald Welte <hwelte@sysmocom.de> + +include::../common/chapters/preface.adoc[] + +include::chapters/overview.adoc[] + +include::chapters/abis.adoc[] + +include::chapters/interfaces.adoc[] + +include::../common/chapters/vty.adoc[] + +include::../common/chapters/logging.adoc[] + +include::chapters/configuration.adoc[] + +include::chapters/bts-models.adoc[] + +include::chapters/architecture.adoc[] + +include::../common/chapters/control_if.adoc[] + +include::../common/chapters/port_numbers.adoc[] + +include::../common/chapters/bibliography.adoc[] + +include::../common/chapters/glossary.adoc[] + +include::../common/chapters/gfdl.adoc[] + |