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New Member

"AVVID QoS Guide" errors(?) and questions.



In the section,

"Configuring Layer 3 Access Lists for VoIP Control Traffic Classification"

of "AVVID QoS Design Guide",

They instruct to use the acl "ACL_IP-PHONES" to configure Layer 3 access lists

for VoIP Control traffic classification.

The acl is supposed to be created in previous

"Marking Control and Management Traffic" section,

and they next show the content as below:

"cat6k-distrib> (enable) set port qos 1/2,3/2 vlan-based

cat6k-distrib> (enable) set qos acl map ACL_IP-PHONES 111

cat6k-distrib> (enable) sh qos acl map run ACL_IP-PHONES

ACL name Type Vlans

-------------------------------- ---- ---------------------------------

ACL_IP-PHONES IP 110,111,112

ACL name Type Ports

-------------------------------- ---- ---------------------------------


cat6k-distrib> (enable) sh qos acl info run ACL_IP-PHONES

set qos acl IP ACL_IP-PHONES


1. dscp 26 tcp any any range 2000 2002

2. dscp 26 tcp any any eq 1720

3. dscp 26 tcp any any range 11000 11999

4. dscp 26 udp any any eq 2427

5. trust-cos any "

Should the acl to use here be "ACL_VOIP_CONTROL",

which is made at the same section, not "ACL_IP-PHONES"?

First of all the "ACL_IP-PHONES" should not be like this,

if it is created as shown in the

"Marking Control and Management Traffic" section.


We are planning to connect as below.

IP Phone --- 3524XL-PWR --- 3508 --- 6500

According to this guide and 3524's reference,

both FastEthernet and GbE interface's out queue

use classification as below and are not user configurable.

Queue # Queue Admission CoS Value

1 0-3

2 4-7

My question is, by default, all control traffic is marked

as Cos & Tos=3 at their source (CCM & IP Phone) and

with above queing strategy, it would not be prioritized.

This does not match the way it is processed

in the Cat6k as explained in the

"Marking Control and Management Traffic" section in the guide.

Since control traffic's priority seems to be configurable from

CCM with the parameters like 'IpTosCm2Dvce',

should I change this from default 3 to 4 so that they

are queued in high priority or is this a mishap to bear

when we use 35XXs as access layer?



Re: "AVVID QoS Guide" errors(?) and questions.

I’d suggest having your Cisco SE look at and validate your design.

New Member

Re: "AVVID QoS Guide" errors(?) and questions.

Thank you for your reply.

We can't hardly be in touch

with savvy SEs in our region.

That's why I posted here.

New Member

Re: "AVVID QoS Guide" errors(?) and questions.

I would suggest emailing the author of the design guide. His name is Todd Truitt.

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