Juniper routers QoS settings for VoIP traffic (SIP based)

Posted on 2011-02-10
Last Modified: 2012-05-11
I have a new setup on Juniper routers for VoIP that is not working so well with quality of service. Typically we use our VoIP setup and control the router which is Sonicwall. In this case, we have little configuration control so looking for best practices for Juniper routers when setting up QoS for VoIP traffic. We have a Vertical Wave phone system in Atlanta with remote IP phones in Utah. There is a site to site VPN tunnel at the router level. Both sides are Juniper routers and the call quality is often perfect and then other times terrible. Clearly a bandwidth management issue. I will update this question tomorrow with exact make/model on each side for the Juniper routers. We are using traditional SIP protocol based IP phones in the remote location but they are traversing through a VPN tunnel rather than purely open on the WAN side. The core side where the phone system is has a minimum of a 3.0 Mbps bonded T-1. Will validate what is on the other side but it is at least a 1.5 Mbps T-1 with only 5-6 people behind it. Any help is appreciated.
Question by:David Roberts
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LVL 18

Accepted Solution

deimark earned 500 total points
ID: 34871415
Have a look at the following link

Although this is for Junos 10.4, the concept is similar for some older versions (and we can of course look at the junos docs for whatever version you have for details)

The basics are we define the various queues available to the OS, define any scheduler or maps we want to this and then implement using firewall filters to determine the queue to send the traffic to and policers to throttle the bandwidth available on the outbound interface.

If you have any specific questions, let us know


Author Comment

by:David Roberts
ID: 34871552
Sounds good. We are reviewing now plus confirming what has already been attempted in the routers by the primary vendor. we will most likely get access control ourselves shortly and can implement these as needed. I am also working to confirm exact make/models asap. Will provide more feedback shortly.
LVL 18

Expert Comment

ID: 34872102
No worries bud

The link above does have a lot of useful background info as well, to allow you to customise the CoS in any way you want but by far the most common use is the standard 4 queues already defined and the allocation of traffic to those.

Let us know if you have anything else you want to know
LVL 18

Expert Comment

ID: 35066982
I answered the question posed in comment 34871415

If its not the answer, I await the askers comments.

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