Ive spent alot of time recently getting to grips with QoS but as yet i have been unable to find a definitive method for calculating traffic rates, CIR Values and Burst values specially for policing on differing links speeds.
For example i have a 2Mbit/s leased line and im configuring QoS on an ASA, ive configured a class for voice and used the class-default for all other traffic, in the policy map i have set priority on the voice class and policed traffic for the best effort class at 1536000 and a burst of 1500 bytes which is 3/4 of the link speed and based on the assumption that i should leave room for voice traffic even though it is priority queued, but i am unsure whether the full link speed on 2000000 should be specified and let the priority handle voice traffic.
access-list voice extended permit tcp any host 184.108.40.206 eq sip
access-list voice extended permit udp any host 220.127.116.11 eq sip
access-list voice extended permit udp any host 18.104.22.168 range 16384 32767
match access-list voice
police output 1536000 1500
police input 1536000 1500
service-policy qos-outside-pol interface outside
Any help would be much appreciated.