Looking for QoS guide for IP phones 1

[notapropergeordie]

Does anyone know of a step by step, plain english, guide to providing Quality of Service for Meridian IP phones over Ethernet LAN & WAN? Ie easier to understand than the Nortel Publications.
Much appreciated.

 

[I2007]

Ehhhh, nothing is easy with with Nortel and IP. You have to specify more what you want. It's not easy to explain how to provide QoS on a few single lines. Do you want to know how to set it up in the network generally or do you want to set it up on the SS or MC32 cards.

i2007

 

[notapropergeordie]

Thanks I2007,
I have been asked to:
"Produce a document that specifies the LAN QoS required for VoIP (for Nortel hard and soft phones) within a single location.
Produce a document that specifies the LAN / WAN QoS required for VoIP (for Nortel hard and soft phones) to external locations e.g. Homeworker with ADSL and i2050, small branch office with router and 4 x i2004"

This is outside of my experience so I was hoping to find that it may be written up some where already.
long shot I know...
Cheers!

 

[I2007]

It depends very much on your network hw. If you have a single location with switches that supports layer3, use the QoS for layer3 called DSCP (akaiffServ). If it is basic switches with layer2 you have to use 802.1Q and differentiate QoS on V-lan's. However if you intend to use i2050 softphones you have to use layer3 QoS because your machine has to be on the same V-Lan if you don't have an extra Ethernet card in the computer connected to a different VLAN. Most new managed swithes today has some form of layer3 QoS but it is very basic. If we talk about homeworkers with ADSL you have to use DiffServ layer3, but the problem is that your ADSL vendor most likely won't support QoS in their backbones. The thing is that every network component in your LAN has to be QoS enabled, and everybody has to talk the same "QoS" language. If one little box doesn't support QoS it can f*Æ* up the entire topology.

i2007