This is correct, but the policy above will nonetheless have an effect.
As it stands, all traffic will be shaped to a peak rate of 1544 kb/s but then policed to 900 kb/s. The end result will be that all traffic will be policed to a rate of 900 kb/s. Any traffic over this rate will be dropped. This is going to have a pretty bad affect on voice traffic. Implementing the changes donmanrobb suggested will resolve this as voice traffic will be excluded from the police statement (but it will still be shaped which is still not good for voice as this can introduce variable delay and cause jitter)
It would probably be better to exclude the voice class from any shape or police statements thus:-
policy-map TUNNEL_QOS
class VOICE
priority 480
class class-default
police rate 900000 bps
conform-action transmit
exceed-action drop
This will give voice traffic 480 kbps of priority bandwith (it will not be able to exceed this amount of bandwith) and police everything else to 900 kbps.
I would recommend using the match protocol rtp statement as indicated above, but for this to work, you will also need the ip nbar protocol-discovery statement on the ingress interface. Alternatively, if you have Cisco IP phones and autoqos is enabled on the switches, this is even better as the voice packets will already be marked appropriately. All you will need is:-
class-map match-all VOICE
match dscp ef
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by: donmanrobbPosted on 2008-03-14 at 23:43:19ID: 21131669
Your right,
Based on the config you posted there is no classification being done at this point.
A class-map would need to be added to fix this such as:
class-map match-all VOICE
match protocol rtp
You could also match the voice traffic using an access-list, so something along the lines of:
access-list 101 permit udp any any range 16384 32767
then class-map VOICE and match ip address 101
Finally if your voip devices like Cisco phones premark the packets with a precedence (5) or DSCP (EF) value you can have the class-map match on those values with match precedence 5 or match dscp ef
Feel free to ask if you have any questions