Need to add 95 Kbits/sec of gold car for each concurrent call to the 4 Mbit/sec link

[manmohan.k]

Hi All,

I want to reserve b/w for my IP Phones . please let me know the configuration for b/w revervation on router. my current config is as :

class-map match-any VOICE-RTP

  match access-group 100

class-map match-any VOICE-Control

  match access-group 101

!

policy-map QoS-Policy

  class VOICE-RTP

  class VOICE-Control

  class class-default

   fair-queue

!

access-list 100 permit ip any any precedence critical

access-list 100 permit ip any any dscp ef

access-list 101 permit tcp any any range 2000 2002

access-list 101 permit tcp any any range 11000 11999

i have created a seprate VLAN for IPT.

with Thanks & Regards,

Manmohan

[Robert Craig · Accepted solution]

Your almost there. In your class maps, add the bandwidth command. It would look something like this. Of course, you need to do the math on how much bandwidth you want reserved for each class.

class-map match-any VOICE-RTP

  match access-group 100

  bandwidth 1000   <<-------- This is saying that the pipe the traffic is going through is a 1M (1,000K) pipe

So, based on your post, if you wanted to make sure each phone got 95k which to me means you are using G711 (64k plus some overhead) and accounted for both streams (two way conversation remember), you would need a total of 190k per phone. So, 1000k divided by 190 = 5 phones with a little bit of room. Remember, the bandwidth command doesn't choke down the traffic across the pipe. It just makes sure that at least 1000k of bandwidth (if available from the service provider) is alloted to the class-map you assign it to. It is very easy to create complex class-maps that oversubscribe the WAN pipe and you end up with little to no QOS over voice traffic. Hope this helps.

[manmohan.k]

Thanks Rebert