Basic QoS for 4500G

[brianhssllc]

I have a situation with a stack of 8 4500Gs where there are softphone users experiencing voice quality problems. There are no VLANs or QoS currently in place.





The softphones have an option to tag traffic as DSCP 46, which according to 3com documentation is "Expedited Forwarding (EF) class: In this class, packets can be forwarded regardless of link share of other traffic. The class is suitable for preferential services with low delay, low packet loss ratio, low jitter, and assured bandwidth"





My question is what needs to be enabled on the switches to do this?  (I doubt that DSCP priorization would just happen automatically without setting some sort of QoS.)





The 3com documentation is a bit sparse but it appears that I need to:


 - set priority trust so that the DSCP packet priority level takes precedence over port priority


 - set SP or WFQ queue scheduling on each port





Does that seem accurate or am I missing something?  Do I need to setup ACL or VLANs?