That won't work 1. any voice media streams that are terminated on the Gatekeeper would end up being set to IP Precedence 3 instead of to EF
2. the requirement is to set the signaling to CS3 I actually thought about this and came up with an out of the box solution. Instead of picking up the traffic and marking it on the inbound interface IAW best practice, simply classify and mark on the interfaces outbound from the router. Still want to hear Vik and Mark's thoughts though..... They are very quiet lately.... Cliff ----- Original Message ----- From: "Chris Parker" <[email protected]> To: "Ameha Negash Haile" <[email protected]> Cc: <[email protected]> Sent: Tuesday, April 14, 2009 11:16 AM Subject: Re: [OSL | CCIE_Voice] QoS - H323 RAS signal marking I found one interesting solution to this: access-list 101 permit ip host <GK IP> host <CME IP> access-list 101 permit ip host <GK IP> host <CCM PUB IP> access-list 101 permit ip host <GK IP> host <CCM SUB IP> ! route-map ras permit 10 match ip address 101 set ip precedence 3 set ip tos 0 ! ip local policy route-map ras Chris Ameha Negash Haile wrote: > > Hello, > > > > First of all, thanks for the lots of great stuff on this list. I have > been reading the various postings for very long. Now I have got some > thought and I like to get your opinions on it. > > > > The question reads as “Mark SCCP, MGCP, H323 and SIP signaling traffic > to CS3. Configure only on routers and CallManager.” > > > > The configuration on CallManager is straight forward. Regarding the > configuration on routers, the solutions I have seen use access lists > to capture interesting traffic (including h323 ras traffic at UDP port > 1719), create policy-map to mark the traffic to CS3, and apply service > policy in the inbound direction of voice VLAN interfaces on the > various routers. > > > > As the above doesn't take into account traffic generated from the > routers themselves, commands like 'ip qos dscp cs3 signaling' under > VoIP dial-peers and 'mgcp ip qos dscp cs3 signaling' on MGCP gateways > are also used. I haven't seen any similar command for H323 RAS traffic > generated from BR2 router and destined to the Gatekeeper on the HQ > router as well as H323 RAS traffic generated from the gatekeeper > (destined to the BR2 router or the CallManager gatekeeper controlled > intercluster trunk). > > > > To provide a comprehensive solution that includes H323 RAS signaling > traffic, what I think needs to be done is, combine the marking and > queuing in the policy-map that is applied on the serial WAN interface > in the outbound direction. While this takes care of the H323 RAS > traffic between BR2 router (H323 gateway) and HQ router (H323 > gatekeeper), to take care of the H323 RAS traffic from the gatekeeper > to CallManager, we need to create a policy-map for marking and apply > it on the server vlan interface in the outbound direction. > > > > A sample configuration for the portion from HQ to BR2 will be like: > > > > ! > > Class-map match-any Voice > > match ip dscp ef > > class-map match-any Signal > > match protocol h323 > > match protocol skinny > > match protocol mgcp > > match protocol sip > > ! > > ! Here we have accounted for all signaling traffic specified > > ! in the question. If we want, we may add 'match ip dscp > > ! cs3' and 'match ip dscp af31' before the ‘match protocol’ commands. > > ! The 'match protocol' commands will be used to capture leftovers. > > ! > > policy-map LLQ-Mark-HQ-BR2 > > class Voice > priority 96 > compress header ip rtp > class Signal > bandwidth 40 > > set ip dscp cs3 ! We do the marking here. > class class-default > fair-queue > > ! > > policy-map MQC-768 > > class class-default > > shape average 729600 7296 0 > > service-policy LLQ-Mark-HQ-BR2 > > ! > > map-class frame-relay FRTS-768 > > service-policy output MQC-768 > > frame-relay fragment 960 > > ! > > interface Serial0/1.10 point-to-point > > bandwidth 768 > > ip address 10.10.10.3 255.255.255.0 > > frame-relay interface-dlci 310 > > class FRTS-768 > > ! > > > > By doing this, I believe we make sure all signaling traffic from HQ to > BR2 will be marked to CS3 before leaving the HQ router. We do the same > on the BR2 router also for traffic going to HQ. > > > > In my opinion, if we don't do the above, in addition to > not properly marking H323 RAS traffic to CS3, we also miss H323 RAS > traffic from the class-map Signal and the LLQ bandwidth guarantee > won’t apply to it. I say this because what I have seen was that H323 > RAS traffic is by default marked as 'DSCP 0', not even AF31. If this > is the case, during congestion, RAS packets can be dropped big time!! > > > > I will appreciate your ideas on this. > > > > Thanks, > > Ameha Haile > > > > P.S. By the way, I find using 'match protocol' commands in class-map > easier than using access groups and access lists. I don't have to > worry about source ports and destination ports although knowing them > is good. Could there be any other reasons, which I might be missing, > to use one method over another for matching traffic? > > > > > > > ------------------------------------------------------------------------ > Create a cool, new character for your Windows Live™ Messenger. Check > it out <http://go.microsoft.com/?linkid=9656621>
