[asterisk-users] TOS bits, DSCP, Asterisk & Polycom

[Doug]

Has anyone figured this out yet?

Lots of places say to add the following
to sip.conf of an Asterisk 1.2 system
(current production machine/Asterisk as root):

   tos=0xB8

   (Hex B8 = Decimal 184 = Binary 10111000)

or if you are running Asterisk v1.4 or newer:

   tos_sip=cs3          ; Sets TOS for SIP packets.
   tos_audio=ef         ; Sets TOS for RTP audio packets.
   tos_video=af41       ; Sets TOS for RTP video packets.


To match the current 1.2 machine would I set the Polycom's
sip.cfg to the first or second QOS option?

Option 1:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    <QOS>
       <Ethernet>
          <RTP
            qos.ethernet.rtp.user_priority="5"/>
          <CallControl
            qos.ethernet.callControl.user_priority="5"/>
          <Other qos.ethernet.other.user_priority="2"/>
       </Ethernet>

       <IP>
          <RTP
            qos.ip.rtp.dscp=""
            qos.ip.rtp.min_delay="1"
            qos.ip.rtp.max_throughput="1"
            qos.ip.rtp.max_reliability="1"
            qos.ip.rtp.min_cost="0"
            qos.ip.rtp.precedence="5"/>

          <CallControl
            qos.ip.callControl.dscp=""
            qos.ip.callControl.min_delay="1"
            qos.ip.callControl.max_throughput="1"
            qos.ip.callControl.max_reliability="1"
            qos.ip.callControl.min_cost="0"
            qos.ip.callControl.precedence="5"/>
       </IP>
    </QOS>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


Option 2:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    <QOS>
       <Ethernet>
          <RTP
            qos.ethernet.rtp.user_priority="5"/>
          <CallControl
            qos.ethernet.callControl.user_priority="5"/>
          <Other qos.ethernet.other.user_priority="2"/>
       </Ethernet>

       <IP>
          <RTP
            qos.ip.rtp.dscp="ef"
            qos.ip.rtp.min_delay="1"
            qos.ip.rtp.max_throughput="1"
            qos.ip.rtp.max_reliability="1"
            qos.ip.rtp.min_cost="0"
            qos.ip.rtp.precedence="5"/>

          <CallControl
            qos.ip.callControl.dscp="ef"
            qos.ip.callControl.min_delay="1"
            qos.ip.callControl.max_throughput="1"
            qos.ip.callControl.max_reliability="1"
            qos.ip.callControl.min_cost="0"
            qos.ip.callControl.precedence="5"/>
       </IP>
    </QOS>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

or none of the above?

Also, how does "10111000" Fit into:

               [ 0   1   2  ]  [3]  [4]  [5]  [6       7]
               [ Precedence ]  [D]  [T]  [R]  [ECN Field]

Is it read backwards?

Any helpful comments appreciated.

References:

   <http://en.wikipedia.org/wiki/Type_of_Service#Type_of_Service>

   <http://en.wikipedia.org/wiki/DiffServ#Expedited_Forwarding_.28EF.29_PHB_-_DSCP.3D.2846_OR_101110.29>

   <http://www.voip-info.org/tiki-index.php?page=Asterisk+sip+tos>

   <http://www.polycom.com/global/documents/support/setup_maintenance/products/voice/SoundPointIP_SoundStationIP_AdminGuide_SIP3_0_Eng_Rev_A.pdf>