ServiceProvider ratelimited IP connection with QOS

[Sascha Monteiro]

Hi,

we have a SP who delivers IP connections with QOS, but they rate-limit on what you leased.

I.e. 2Mb, and they police to it.

But the access speed can be i.e. 100Mb!

We can send up to the rate limit on priority traffic, so CAC is in place on the callmanager.

(yes, a VoIP environment)

Q: do I need to shape my traffic to 2Mb??

or doesn't it matter as the network polices?

(as long as my voip goes through)

someone told me that because of the speed mismatch (100Mb->2Mb) there might be drops anyway even voip

thanks

[pkhatri]

Hi,

What you have is not uncommon. Not every Ethernet service has to run at the line-rate. So, in answer to your question:

Yes. You need to shape. While it is true that there will be drops regardless of whether you shape or let the provider police, it is better to shape it out yourself. If you shape your traffic, then you have control over what gets through first and what gets dropped. If you just send traffic out and let the provide police, the traffic will be dropped indiscriminately. Therefore, you are better off putting service policies on your outbound interface to control queuing of your traffic.

Hope that helps,

Paresh.