If your a VoIP user like me, chances are you don’t have an explicit policy installed on your router for ensuring that your voice data is a higher priority than other data. This excellent post by the user Celeron shows users how to configure QOS on Cisco routers. This configuration ensures that when your outbound links get full, it will prioritize VoIP traffic over other traffic to ensure your phone calls are uninterrupted.
Sample Config
!
class-map match-all voice-traffic
match ip rtp 10000 10000
!
!
policy-map voice-policy
class voice-traffic
priority 200
class class-default
fair-queue
policy-map shaper
class class-default
shape average 350000 3500 0
service-policy voice-policy
!
interface
service-policy output shaper
!
July 1, 2007 
