[CUWiN-Dev] IIT VoIP lab - requests?

[William Waites]

On Fri, Feb 24, 2006 at 01:11:21PM -0600, Paul Smith wrote:
> 
> We spoke yesterday and decided to focus on two variables for testing: one is
> varying TOS in the IP header to prioritize SIP protocol packets over say
> HTTP, and the other is setting up a multi-hop network in the lab and seeing
> what happens to a SIP session when a node goes down.

Hi Paul. Greetings from Jo'burg!

Just a note about diffserv and VoIP.

Strictly speaking, any type of diffserv should be applied to the
RTP packets, not the SIP packets. In an environment where you don't
have particular control over the client software (i.e. outside the lab)
it might be necessary to re-write the headers to set a known TOS value
at the ingress gateway. But you can't just, say, match on port 5060
since the RTP streams will use random UDP ports and it's these flows
that we really care about.

-w