From: Avner Izhar (aizhar@ccbootcamp.com)
Date: Tue Oct 02 2007 - 01:29:48 ART
Hello Antonio,
First regarding the need, it is needed in a campus network, even if it is giga to the desktop because of congestions and oversubscription.
A short delay which is unnoticeable in a data environment, say 100 ms, might cause a slight degraded audio to the users.
As for the implementation, have you considered 'autoqos voip' ? It works and take out the need for complex configuration.
If you choose to do it manually, make sure you take care of cos to queue mapping (so cos 5 goes to the strict priority queue) and cos to dscp mapping since the default is not cos 5 = dscp 46 .
HTH,
-------------------------------------------
thanks,
Avner Izhar
CCIE#15999 (Voice), CCVP, CCSI# 31623
Technical Instructor
CCBOOTCAMP - A Cisco Sponsored Organization (SO)
Email: aizhar@ccbootcamp.com
Toll Free: 877-654-2243
Direct: +1-702-968-5100 = Outside the USA
FAX: +1-702-446-8012
YES! We take Cisco Learning Credits!
Register to win a free iPhone! http://www.ccbootcamp.com/iphone.html
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Antonio Soares
Sent: Tuesday, October 02, 2007 00:46
To: ccielab@groupstudy.com
Subject: QoS in a Campus Network with IP Telephony Solution
Importance: Low
Hello group,
I need to configure QoS in a Campus Network composed of several 3750s, 4500s
and 6500s. I'm looking for the minimal config in order to avoid potential
voice quality issues. Right now i have this:
##############################
Catalysts 3750:
##############################
4Q3T (or 1P3Q3T)
##############################
Ports with PC+IP Phone:
##############################
mls qos trust cos
mls qos trust extend cos 0
priority-queue out
##############################
Uplinks:
##############################
mls qos trust dscp
priority-queue out
##############################
##############################
Catalysts 4500:
##############################
4Q1T (or 1P3Q1T)
##############################
Ports with PC+IP Phone:
##############################
qos trust cos
qos trust extend cos 0
tx-queue 3
priority high
##############################
Uplinks:
##############################
mls qos trust dscp
tx-queue 3
priority high
##############################
##############################
Catalyst 6500:
##############################
Ports with PC+IP Phone:
##############################
WS-X6148-45AF
2Q2T
WS-X6348-RJ-45
2Q2T
##############################
mls qos trust cos
mls qos trust extend cos 0
##############################
Uplinks:
##############################
WS-X6724-SFP
1P3Q8T
##############################
mls qos trust dscp
priority-queue cos-map 1 5
##############################
Voice Servers:
##############################
WS-X6748-GE-TX
1P3Q8T
##############################
mls qos trust dscp
priority-queue cos-map 1 5
##############################
I know that Cisco provides a QoS Network Design Guide:
http://www.cisco.com/application/pdf/en/us/guest/netsol/ns432/c649/ccmigrati
on_09186a008049b062.pdf
But i really wonder if i need to implement all those complex configurations
to accomplish my goal.
Any sugestions are welcome.
Thanks.
Regards,
Antonio Soares
CCIE #18473, CCNP, CCIP
http://pwp.netcabo.pt/amsoares/
This archive was generated by hypermail 2.1.4 : Fri Nov 16 2007 - 13:11:11 ART