Mailing List Archive

Well Scuba Jason,

IOS has always marked control traffic as AF31, as well as SCCP control
traffic for registered media resources.

The two things I have seen recommended and done are:

1. Change the settings per dial-peer / sccp config (technically this is ip
precedence 3, which aligns loosely with cs3, as they share the first 3 bits)
2. Use a match-any for cs3 and af31 in your class maps

From the QoS SRND:

"The QoS Baseline recommends marking Call-Signaling to CS3. However,
currently most Cisco IP Telephony products mark Call-Signaling to AF31. A
marking migration from AF31 to CS3 is under way within Cisco, but in the
interim it is recommended that both AF31 and CS3 be reserved for
Call-Signaling and that Locally-Defined Mission-Critical Data applications
be marked to a temporary placeholder non-standard DSCP, such as 25. Upon
completion of the migration, the QoS Baseline marking recommendations of
CS3 for Call-Signaling and AF31 for Locally-Defined Mission-Critical Data
applications should be used. These marking recommendations are more in line
with RFC 2474 and RFC 2597."

Source
<https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book/QoSIntro.html>

Though, this "transition period" seems to have gone on indefinitely.

FWIW, I have never seen a global command to switch it, and the documentation
<https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/voice/vcr2/vcr2-cr-book/vcr-i1.html#wp3986668457>
doesn't tell us that there is one for dial-peer signaling. The sccp
command is global.

Stay buoyant!

On Thu, Apr 23, 2020 at 1:55 PM Jason Aarons <scubajasona@gmail.com> wrote:

> CallManager marks control traffic as CS3, but just see that IOS-XE on 4431
> 16.09.05 marks control as AF31 by default.
>
> Is there a global IOS command to change IOS-XE to use CS3 ? Rather then on
> a per dial-peer level?
>
> All my class maps to protect control are based on CS3.
>
> Hope all is well here. Work changed emails couple times and that created
> challenges! I still read every week, but changed emails so I can actually
> reply again!
>
> -jason
> _______________________________________________
> cisco-voip mailing list
> cisco-voip@puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-voip
>

There is the dscp-profile command under voice services voip -> sip

Never used it but if it’s going to be somewhere I’d expect it to be there.

> On Apr 23, 2020, at 14:55, Anthony Holloway <avholloway+cisco-voip@gmail.com> wrote:
>
> ?
> Well Scuba Jason,
>
> IOS has always marked control traffic as AF31, as well as SCCP control traffic for registered media resources.
>
> The two things I have seen recommended and done are:
>
> 1. Change the settings per dial-peer / sccp config (technically this is ip precedence 3, which aligns loosely with cs3, as they share the first 3 bits)
> 2. Use a match-any for cs3 and af31 in your class maps
>
> From the QoS SRND:
>
> "The QoS Baseline recommends marking Call-Signaling to CS3. However, currently most Cisco IP Telephony products mark Call-Signaling to AF31. A marking migration from AF31 to CS3 is under way within Cisco, but in the interim it is recommended that both AF31 and CS3 be reserved for Call-Signaling and that Locally-Defined Mission-Critical Data applications be marked to a temporary placeholder non-standard DSCP, such as 25. Upon completion of the migration, the QoS Baseline marking recommendations of CS3 for Call-Signaling and AF31 for Locally-Defined Mission-Critical Data applications should be used. These marking recommendations are more in line with RFC 2474 and RFC 2597."
>
> Source
>
> Though, this "transition period" seems to have gone on indefinitely.
>
> FWIW, I have never seen a global command to switch it, and the documentation doesn't tell us that there is one for dial-peer signaling. The sccp command is global.
>
> Stay buoyant!
>
>> On Thu, Apr 23, 2020 at 1:55 PM Jason Aarons <scubajasona@gmail.com> wrote:
>> CallManager marks control traffic as CS3, but just see that IOS-XE on 4431 16.09.05 marks control as AF31 by default.
>>
>> Is there a global IOS command to change IOS-XE to use CS3 ? Rather then on a per dial-peer level?
>>
>> All my class maps to protect control are based on CS3.
>>
>> Hope all is well here. Work changed emails couple times and that created challenges! I still read every week, but changed emails so I can actually reply again!
>>
>> -jason
>> _______________________________________________
>> cisco-voip mailing list
>> cisco-voip@puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-voip
> _______________________________________________
> cisco-voip mailing list
> cisco-voip@puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-voip

I don't know. It both:

1. Looks like it's for SIP only (so not a global dial-peer solution)
2. Looks like it's mapping Resource Priority Headers (RPH) to DSCP values,
as opposed to setting DSCP values directly

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/voice/vcr2/vcr2-cr-book/vcr-d2.html#wp2315757579


I have no idea what RHP at this time, though I see there is a whole RFC on
the topic I could read. However, if someone has a summary of what it is,
that would be appreciated.

On Thu, Apr 23, 2020 at 3:36 PM UC Penguin <gentoo@ucpenguin.com> wrote:

> There is the dscp-profile command under voice services voip -> sip
>
> Never used it but if it’s going to be somewhere I’d expect it to be there.
>
> On Apr 23, 2020, at 14:55, Anthony Holloway <
> avholloway+cisco-voip@gmail.com> wrote:
>
> ?
> Well Scuba Jason,
>
> IOS has always marked control traffic as AF31, as well as SCCP control
> traffic for registered media resources.
>
> The two things I have seen recommended and done are:
>
> 1. Change the settings per dial-peer / sccp config (technically this is ip
> precedence 3, which aligns loosely with cs3, as they share the first 3 bits)
> 2. Use a match-any for cs3 and af31 in your class maps
>
> From the QoS SRND:
>
> "The QoS Baseline recommends marking Call-Signaling to CS3. However,
> currently most Cisco IP Telephony products mark Call-Signaling to AF31. A
> marking migration from AF31 to CS3 is under way within Cisco, but in the
> interim it is recommended that both AF31 and CS3 be reserved for
> Call-Signaling and that Locally-Defined Mission-Critical Data applications
> be marked to a temporary placeholder non-standard DSCP, such as 25. Upon
> completion of the migration, the QoS Baseline marking recommendations of
> CS3 for Call-Signaling and AF31 for Locally-Defined Mission-Critical Data
> applications should be used. These marking recommendations are more in line
> with RFC 2474 and RFC 2597."
>
> Source
> <https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book/QoSIntro.html>
>
> Though, this "transition period" seems to have gone on indefinitely.
>
> FWIW, I have never seen a global command to switch it, and the
> documentation
> <https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/voice/vcr2/vcr2-cr-book/vcr-i1.html#wp3986668457>
> doesn't tell us that there is one for dial-peer signaling. The sccp
> command is global.
>
> Stay buoyant!
>
> On Thu, Apr 23, 2020 at 1:55 PM Jason Aarons <scubajasona@gmail.com>
> wrote:
>
>> CallManager marks control traffic as CS3, but just see that IOS-XE on
>> 4431 16.09.05 marks control as AF31 by default.
>>
>> Is there a global IOS command to change IOS-XE to use CS3 ? Rather then
>> on a per dial-peer level?
>>
>> All my class maps to protect control are based on CS3.
>>
>> Hope all is well here. Work changed emails couple times and that created
>> challenges! I still read every week, but changed emails so I can actually
>> reply again!
>>
>> -jason
>> _______________________________________________
>> cisco-voip mailing list
>> cisco-voip@puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-voip
>>
> _______________________________________________
> cisco-voip mailing list
> cisco-voip@puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-voip
>
>