I have found the one setting in the configuration about prioritizing delay sensitive data, but not much else on the router...
Background: Have a client who added a Barracuda spam filter to their network, and redirected their email (10,000+ a day) from their ISP to their 768k fractional T1.... On this same T1 they also have an Axxess VOIP setup for their remote offices. Router is a Netopia R5300 T1.
Problem: Since the introduction of the Barracuda, DNS calls and SMTP traffic seem to have congested the circuit a lot, and voice users complain of call cutting out. T1 provider reports that the circuit is not at full utilization, but that there is a lot of DNS traffice being generated from the Barracuda. In looking at the configuration of the Netopia I see no way of prioritizing data by port/protocol (like you would find in a Cisco)...
Question: Am I missing something here... Is there some way to give VOIP priority on the router over DNS and SMTP traffic... or am I stuck with the one yes/no checkbox for prioritizing time sensitive data?
Any guidance would be appreciated.