1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
|
msc {
hscale=2;
ms [label="MS"],
bts [label="BTS"],
bsc_l [label="BSC(lchan SDCCH)"],
bsc_l2 [label="BSC(lchan TCH)"],
bsc [label="BSC"],
mgw [label="MGW@BSC"],
m_sc [label="MSC"];
...;
--- [label="MS Requests dedicated channel"];
ms -> bts [label="RACH: REQ"];
bts -> bsc [label="RSL Cchan CHAN RQD"];
bsc_l <= bsc [label="allocate lchan (RR IMM ASS)", textcolor="red", linecolor="red"];
bts <- bsc_l [label="RSL Dchan (SDCCH) CHAN ACT"];
bts -> bsc_l [label="RSL Dchan (SDCCH) CHAN ACT ACK"];
bts <- bsc_l [label="RSL Cchan IMM ASS (RR IMM ASS)"];
bsc_l box bsc_l [label="Start T3101"];
ms <- bts [label="AGCH: RR IMM ASS"];
--- [label="MS Establishes SDCCH"];
ms -> bts [label="SDCCH: SABM (CM SERV REQ)"];
ms <- bts [label="SDCCH: UA (CM SERV REQ)"];
bts -> bsc_l [label="RSL RLL (SDCCH, SAPI0, DCCH) EST IND", textcolor="green", linecolor="green"];
bsc_l box bsc_l [label="Stop T3101"];
bsc_l => bsc [label="GSCON_EV_A_CONN_REQ", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP CR (BSSMAP COMPL L3 (CM SERV REQ))"];
bsc <- m_sc [label="SCCP CC"];
bsc -> bsc [label="GSCON_EV_A_CONN_CFM", textcolor="red", linecolor="red"];
ms box m_sc [label="Authentication, MM info, ..."];
bsc <- m_sc [label="SCCP DT1 (DTAP (CM SERV ACK)"];
bsc -> bsc [label="GSCON_EV_MT_DTAP", textcolor="red", linecolor="red"];
bsc_l <= bsc [label="lchan_submit_dtap(CM SERV ACK)", textcolor="red", linecolor="red"];
bts <- bsc_l [label="RSL RLL (SDCCH) DATA REQ (CM SERV ACK)", textcolor="green", linecolor="green"];
ms <- bts [label="SDCCH: I (CM SERV ACK)"];
ms -> bts [label="SDCCH: I (CC SETUP)"];
bts -> bsc_l [label="RSL RLL (SDCCH) DATA IND (CC SETUP)", textcolor="green", linecolor="green"];
bsc_l -> bsc [label="GSCON_EV_MO_DTAP", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP DT1 (DTAP (CC SETUP))"];
...;
--- [label="MSC assigns Voice Channel (TCH)"];
bsc <- m_sc [label="SCCP DT1 (BSSMAP ASSIGNMENT CMD)"];
bsc -> bsc [label="GSCON_EV_A_ASSIGNMENT_CMD", textcolor="red", linecolor="red"];
bsc_l2 <= bsc [label="allocate lchan", textcolor="red", linecolor="red"];
bts <- bsc_l2 [label="RSL Dchan (TCH) CHAN ACT"];
bts -> bsc_l2 [label="RSL Dchan (TCH) CHAN ACT ACK"];
bts <- bsc_l [label="RSL RLL (SDDCH) DATA REQ (RR ASSIGNMENT CMD)", textcolor="green",
linecolor="green"];
bsc_l2 box bsc_l2 [label="Start T3107"];
ms <- bts [label="SDCCH: I (RR ASSIGNMENT CMD)"];
ms box ms [label="local-end RLL release", textcolor="green", linecolor="green"];
bts -> bsc_l [label="RSL RLL (SDCCH) REL IND", textcolor="gray", linecolor="green"];
bsc_l => bsc [label="GSCON_EV_RLL_REL_IND", textcolor="gray", linecolor="red"];
bts -> bsc_l [label="RSL Dchan (SDCCH) CONN FAIL IND", textcolor="gray", linecolor="green"];
bsc_l => bsc [label="GSCON_EV_CONN_FAIL", textcolor="gray", linecolor="red"];
bsc_l box bsc_l [label="BSC must ignore failures on old channel"];
ms -> bts [label="TCH: SABM (RR ASSIGNMENT CMPL)"];
ms <- bts [label="TCH: UA (RR ASSIGNMENT CMPL)"];
bts -> bsc_l2 [label="RSL RLL (TCH, SAPI0, DCCH) EST IND", textcolor="green", linecolor="green"];
bsc_l2 box bsc_l2 [label="Stop T3107"];
bsc_l2 => bsc [label="GSCON_EV_RR_ASS_COMPL", textcolor="red", linecolor="red"];
bsc_l <= bsc [label="release_lchan(SDCCH)", textcolor="red", linecolor="red"];
bts box bsc_l [label="local-end RLL release", textcolor="green", linecolor="green"];
bts <- bsc_l [label="RSL Dchan (SDCCH) RF CHAN REL"];
bts <- bsc_l [label="RSL RLL (SDCCH, SAPI0, DCCH) REL REQ", textcolor="gray", linecolor="green"];
bts <- bsc_l [label="RSL DChan (SDCCH) DEACTIVATE SACCH", textcolor="gray", linecolor="black"];
bts -> bsc_l [label="RSL RLL (SDCCH, SAPI0, DCCH) RF FAIL IND", textcolor="gray", linecolor="green"];
bts -> bsc_l [label="RSL Dchan (SDCCH, SAPI0, DCCH) RF CHAN REL ACK"];
# connect BTS RTP with BSC-MGW RTP
--- [label="BSC configures RTP on BTS and both sides of MGW"];
bts <- bsc [label="RSL IPA CRCX", textcolor="blue", linecolor="blue"];
bts box bts [label="Bind to BTS-local RTP Port (1000)", textcolor="blue", linecolor="blue"];
bts -> bsc [label="IPA CRCX ACK (BTS:1000)", textcolor="blue", linecolor="blue"];
bsc -> mgw [label="MGCP CRCX rtpbridge/2@mgw (BTS:1000)", textcolor="blue", linecolor="blue"];
mgw box mgw [label="Bind to MGW-local RTP Port (2000)\nConnect to BTS:1000", textcolor="blue", linecolor="blue"];
bsc <- mgw [label="MGCP CRCX rtpbridge/2@mgw OK (MGW:2000)", textcolor="blue", linecolor="blue"];
bts <- bsc [label="IPA MDCX (MGW:2000)", textcolor="blue", linecolor="blue"];
bts box bts [label="Connect RTP socket to remote (MGW) RTP Port", textcolor="blue", linecolor="blue"];
bts -> bsc [label="IPA MDCX ACK", textcolor="blue", linecolor="blue"];
bsc >> mgw [label="MGCP MDCX rtpbridge/2@mgw", textcolor="gray", linecolor="gray"];
bsc << mgw [label="MGCP MDCX rtpbridge/2@mgw OK", textcolor="gray", linecolor="gray"];
...;
--- [label="BSC finally can report successful TCH assignment"];
bsc -> m_sc [label="SCCP DT1 (BSSMAP ASSGN CMPL (3GPP AoIP MGW:3000))"];
m_sc box m_sc [label="Connect remote RTP to MGW addr from ASSGN CMPL"];
...;
mgw <-> m_sc [label="RTP Audio MGW:3000 MSC:4000", textcolor="blue", linecolor="blue"];
bts <-> mgw [label="RTP Audio BTS:1000 MGW:2000", textcolor="blue", linecolor="blue"];
ms <-> bts [label="Um Audio (bidirectional)", textcolor="blue", linecolor="blue"];
ms <-> m_sc [label="DTAP CC ALERTING"];
...;
--- [label="Further signalling in parallel with RTP (simplified)"];
ms <- m_sc [label="DTAP CC CONNECT"];
ms -> m_sc [label="DTAP CC CONNECT ACK"];
--- [label="Voice Call in Progress"];
...;
--- [label="B-end hangs up"];
ms <- m_sc [label="DTAP CC DISCONNET"];
ms <- m_sc [label="DTAP CC RELEASE"];
ms <- m_sc [label="DTAP CC RELEASE COMPL"];
...;
bsc <- m_sc [label="SCCP DT1 (BSSMAP CLEAR CMD)"];
bsc -> bsc [label="GSCON_EV_A_CLEAR_CMD", textcolor="red", linecolor="red"];
--- [label="BSC must release terrestrial resoures before reporting CLEAR COMPLETE"];
mgw <- bsc [label="MGCP DLCX rtpbridge/2@mgw", textcolor="blue", linecolor="blue"];
mgw box mgw [label="Release MSC-facing local RTP port (3000)", textcolor="blue", linecolor="blue"];
mgw -> bsc [label="MGCP DLCX rtpbridge/2@mgw OK", textcolor="blue", linecolor="blue"];
mgw <- bsc [label="MGCP DLCX rtpbridge/2@mgw", textcolor="blue", linecolor="blue"];
mgw box mgw [label="Release BTS-facing local RTP port (2000)", textcolor="blue", linecolor="blue"];
mgw -> bsc [label="MGCP DLCX rtpbridge/2@mgw OK", textcolor="blue", linecolor="blue"];
bts <- bsc [label="IPA DLCX", textcolor="blue", linecolor="blue"];
bts box bts [label="Release BTS-local RTP port (1000)", textcolor="blue", linecolor="blue"];
bts -> bsc [label="IPA DLCX OK", textcolor="blue", linecolor="blue"];
bsc -> bsc [label="GSCON_EV_RSL_CLEAR_COMPL", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP DT1 (BSSMAP CLEAR COMPL)"];
bsc <- m_sc [label="SCCP RLSD"];
bsc -> bsc [label="GSCON_EV_A_DISC_IND", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP RLC"];
--- [label="BSC releases radio resources after CLEAR COMPLETE"];
bsc_l2 <= bsc [label="release_lchan(TCH)", textcolor="red", linecolor="red"];
bts <- bsc_l2 [label="RSL RLL (TCH, SAPI0, DCCH) DATA REQ (RR CHANNEL RELEASE)", textcolor="green", linecolor="green"];
bsc_l2 box bsc_l2 [label="Start T3109"];
bts <- bsc_l2 [label="RSL Dchan (TCH) DEACTIVATE SACCH"];
ms <- bts [label="TCH: I (RR CHANNEL RELEASE)"];
ms -> bts [label="TCH: DISC (RR CHANNEL RELEASE)"];
bts -> bsc_l2 [label="RSL RLL (TCH, SAPI0, DCCH) REL IND", textcolor="green", linecolor="green"];
bsc_l2 => bsc [label="GSCON_EV_RLL_REL_IND", textcolor="red", linecolor="red"];
bsc_l2 box bsc_l2 [label="Stop T3109; Start T3111"];
# optional: Conn Fail?
bts <- bsc_l2 [label="RSL Dchan (TCH, SAPI0, DCCH) RF CHAN REL"];
bts -> bsc_l2 [label="RSL Dchan (TCH, SAPI0, DCCH) RF CHAN REL ACK"];
bsc_l2 box bsc_l2 [label="T3111 timeout: Channel can be used again"];
...;
}
|
