QoS for VoIP traffic

[Shurik]

Our client installed new VoIP solution, and they are experiencing phone drops...

In my mind I thought that enabling and configuring the QoS will solve the problem. But, I was on call with CP support, and they said that QoS won't prioritize the traffic unless the interface is fully utilized. It sounds a bit odd to me... Does it really work this way?

Is there anything else I can do to fix the VoIP issue?

Thank you!

[PhoneBoy · Accepted solution]

What version/JHF level?
In general, TAC is correct: QoS may not do much, if anything, if the interface is not fully utilized.
Also, for maximum effectiveness, it needs to be enforced in multiple places in the network (not just on a perimeter gateway).

[Shurik]

I see... so it's not a real QoS.

It's SMB device, 77.20, managed by 80.30 (don't remember exact JHF)

[HristoGrigorov]

Well, if interface is not fully utilized then there should not be any packet delays and QoS will not have anything to prioritize being it real or not. But you mention SMB and as you probably know these are not very powerful devices. Performance largely depends on what blades are enabled and how is your rule base constructed. There are few places to try to optimize traffic and get rid of these drops.