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diff --git a/doc/tex/qos.tex b/doc/tex/qos.tex deleted file mode 100644 index 422f12949..000000000 --- a/doc/tex/qos.tex +++ /dev/null @@ -1,144 +0,0 @@ -\subsubsection{Introduction} - -Asterisk supports different QoS settings at the application level for various -protocols on both signaling and media. The Type of Service (TOS) byte can be -set on outgoing IP packets for various protocols. The TOS byte is used by the -network to provide some level of Quality of Service (QoS) even if the network -is congested with other traffic. - -Asterisk running on Linux can also set 802.1p CoS marks in VLAN packets for the -VoIP protocols it uses. This is useful when working in a switched environment. -In fact Asterisk only set priority for Linux socket. For mapping this priority -and VLAN CoS mark you need to use this command: - -\begin{verbatim} -vconfig set_egress_map [vlan-device] [skb-priority] [vlan-qos] -\end{verbatim} - -The table below shows all VoIP channel drivers and other Asterisk modules that -support QoS settings for network traffic. It also shows the type(s) of -traffic for which each module can support setting QoS settings. - -\begin{table}[h!] -\begin{center} -\begin{tabular}{ | l || c | c | c | c | } - \hline - & Signaling & Audio & Video & Text \\ \hline \hline - chan\_sip & + & + & + & + \\ \hline - chan\_skinny & + & + & + & \\ \hline - chan\_mgcp & + & + & & \\ \hline - chan\_unistm & + & + & & \\ \hline - chan\_h323 & & + & & \\ \hline - chan\_iax2 & \multicolumn{4}{|c|}{+} \\ - \hline -\end{tabular} -\end{center} -\caption{Channel Driver QoS Settings} -\end{table} - -\begin{table}[h!] -\begin{center} -\begin{tabular}{ | l || c | c | c | c | } - \hline - & Signaling & Audio & Video & Text \\ \hline \hline - dundi.conf & \multicolumn{4}{ | c | }{+ (tos setting)} \\ \hline - iaxprov.conf & \multicolumn{4}{ | c | }{+ (tos setting)} \\ \hline - \hline -\end{tabular} -\end{center} -\caption{Other ToS Settings} -\end{table} - -\subsubsection{IP TOS values} -The allowable values for any of the tos* parameters are: -CS0, CS1, CS2, CS3, CS4, CS5, CS6, CS7, AF11, AF12, AF13, AF21, AF22, AF23, -AF31, AF32, AF33, AF41, AF42, AF43 and ef (expedited forwarding), - -The tos* parameters also take numeric values. - -Note that on a Linux system, Asterisk must be compiled with libcap in order to -use the ef tos setting if Asterisk is not run as root. - -The lowdelay, throughput, reliability, mincost, and none values have been removed -in current releases. - -\subsubsection{802.1p CoS values} - -Because 802.1p uses 3 bits of the VLAN header, this parameter can take integer -values from 0 to 7. - -\subsubsection{Recommended values} -The recommended values shown below are also included in sample configuration files: - -\begin{table}[h!] -\begin{center} -\begin{tabular}{ | l || l | l | } -\hline - & tos & cos \\ \hline \hline -Signaling & cs3 & 3 \\ \hline -Audio & ef & 5 \\ \hline -Video & af41 & 4 \\ \hline -Text & af41 & 3 \\ \hline -Other & ef & \\ -\hline -\end{tabular} -\end{center} -\caption{Recommended QoS Settings} -\end{table} - -\subsubsection{IAX2} - -In iax.conf, there is a "tos" parameter that sets the global default TOS -for IAX packets generated by chan\_iax2. Since IAX connections combine -signalling, audio, and video into one UDP stream, it is not possible -to set the TOS separately for the different types of traffic. - -In iaxprov.conf, there is a "tos" parameter that tells the IAXy what TOS -to set on packets it generates. As with the parameter in iax.conf, -IAX packets generated by an IAXy cannot have different TOS settings -based upon the type of packet. However different IAXy devices can -have different TOS settings. - -\subsubsection{SIP} - -In sip.conf, there are four parameters that control the TOS settings: -"tos\_sip", "tos\_audio", "tos\_video" and "tos\_text". tos\_sip controls -what TOS SIP call signaling packets are set to. tos\_audio, tos\_video -and tos\_text control what TOS values are used for RTP audio, video, and text -packets, respectively. - -There are four parameters to control 802.1p CoS: "cos\_sip", "cos\_audio", -"cos\_video" and "cos\_text". The behavior of these parameters is the -same as for the SIP TOS settings described above. - -\subsubsection{Other RTP channels} - -chan\_mgcp, chan\_h323, chan\_skinny and chan\_unistim also support TOS and -CoS via setting tos and cos parameters in their corresponding configuration -files. Naming style and behavior are the same as for chan\_sip. - -\subsubsection{Reference} - -IEEE 802.1Q Standard: -\url{http://standards.ieee.org/getieee802/download/802.1Q-1998.pdf} -Related protocols: IEEE 802.3, 802.2, 802.1D, 802.1Q - -RFC 2474 - "Definition of the Differentiated Services Field -(DS field) in the IPv4 and IPv6 Headers", Nichols, K., et al, -December 1998. - -IANA Assignments, DSCP registry -Differentiated Services Field Codepoints -\url{http://www.iana.org/assignments/dscp-registry} - -To get the most out of setting the TOS on packets generated by -Asterisk, you will need to ensure that your network handles packets -with a TOS properly. For Cisco devices, see the previously mentioned -"Enterprise QoS Solution Reference Network Design Guide". For Linux -systems see the "Linux Advanced Routing \& Traffic Control HOWTO" at -\url{http://www.lartc.org/}. - -For more information on Quality of -Service for VoIP networks see the "Enterprise QoS Solution Reference -Network Design Guide" version 3.3 from Cisco at: -\url{http://www.cisco.com/application/pdf/en/us/guest/netsol/ns432/c649/ccmigration\_09186a008049b062.pdf} |