[c-nsp] VOIP QOS

[Fred Reimer]

Yea, you don't want to shape VoIP traffic, you want to place it
in a priority queue and police it to an absolute maximum.  If
there are any slow links in between, you probably want to
configure LFI also.

Fred Reimer, CISSP, CCNP, CQS-VPN, CQS-ISS
Senior Network Engineer
Coleman Technologies, Inc.
954-298-1697




-----Original Message-----
From: cisco-nsp-bounces at puck.nether.net
[mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Church,
Charles
Sent: Thursday, November 08, 2007 12:26 PM
To: Paul Stewart; cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] VOIP QOS

I think you still want to priority queue the VoIP traffic, to cut
down
on jitter.  You need to do that on the main interfaces though. 


Chuck 

-----Original Message-----
From: cisco-nsp-bounces at puck.nether.net
[mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Paul
Stewart
Sent: Thursday, November 08, 2007 10:33 AM
To: cisco-nsp at puck.nether.net
Subject: [c-nsp] VOIP QOS

Hi there...

I know this has been discussed several times and searched the
archives...
I'm being told by a client that this isn't working well.. my
question is
what is a better way to offer this?

5 Meg synchronous connection carrying VOIP (SIP/RTP) and general
Internet
traffic.  Want to prioritize the VOIP and carve out "up to" 2 meg
of
traffic
when needed leaving "up to" 3 meg for general traffic... also
want to be
able to use 4 meg of general traffic when VOIP isn't using much
etc....

Cisco 2821 at customer premise with FE0/0 being the edge
interface -
Cisco
7206VXR on our side with customer connection coming off
subinterface
GigE0/0.101

Between these devices is ethernet equipment that supports DSCP
and is
supposed to prioritize - below you'll see no congestion in place
but on
the
VOIP side we're seeing dropped packets frequently that are not
seen when
we
remove QOS from interfaces indicating something in this config is
wrong....

Any thoughts are appreciated...

Both sides have the following applied outbound on the edge
interface:

class-map match-any VOIP
 match protocol rtp
 match protocol sip
!
!
policy-map QOS-VOIP
 class VOIP
  set dscp ef
  shape average 2000000
 class class-default
  set dscp default
  shape average 3000000


 FastEthernet0/0

  Service-policy output: QOS-VOIP

    Class-map: VOIP (match-any)
      4649311 packets, 996776732 bytes
      5 minute offered rate 401000 bps, drop rate 0 bps
      Match: protocol rtp
        4644189 packets, 993315456 bytes
        5 minute rate 397000 bps
      Match: protocol sip
        5121 packets, 3461062 bytes
        5 minute rate 4000 bps
      QoS Set
        dscp ef
          Packets marked 4649311
      Traffic Shaping
           Target/Average   Byte   Sustain   Excess    Interval
Increment
             Rate           Limit  bits/int  bits/int  (ms)
(bytes)
          2000000/2000000   12500  50000     50000     25
6250

        Adapt  Queue     Packets   Bytes     Packets   Bytes
Shaping
        Active Depth                         Delayed   Delayed
Active
        -      0         4649311   996776732 0         0
no

    Class-map: class-default (match-any)
      1687936 packets, 438092041 bytes
      5 minute offered rate 120000 bps, drop rate 0 bps
      Match: any
      QoS Set
        dscp default
          Packets marked 1680145
      Traffic Shaping
           Target/Average   Byte   Sustain   Excess    Interval
Increment
             Rate           Limit  bits/int  bits/int  (ms)
(bytes)
          3000000/3000000   18750  75000     75000     25
9375

        Adapt  Queue     Packets   Bytes     Packets   Bytes
Shaping
        Active Depth                         Delayed   Delayed
Active
        -      0         1687936   438092041 40206     48842063
no

_______________________________________________
cisco-nsp mailing list  cisco-nsp at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
_______________________________________________
cisco-nsp mailing list  cisco-nsp at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 5188 bytes
Desc: not available
Url : https://puck.nether.net/pipermail/cisco-nsp/attachments/20071108/a97c657f/attachment-0001.bin