[Asterisk-Dev] IP-ID in RTP UDP packets

[Aj]

>
> > - force linux to send the right IP-ID?
> What for?

well, right right behaviour of all the fields in the RTP/UDP/IP
packets are needed for header compression schemes. And without it the
header compression used for VoIP calls will face some problems.

I was wondering if anybody using asterisk has faced issues with this regard...

> > - or to set the DF bit to 0 in an attempt to make the IP stack to put in
> > the right IP-ID?
> Why?
>
> Ask on loonix-kernel instead, this is not an asterisk question.

>From some investigation in about the linux kernel, looks like the
current behaviour is specific to linux implementation. There are long
email threads which discusses problems with header compression with
the current linux implementation. If interested you can read about it
at

http://www.linuxsa.org.au/pipermail/linuxsa/2003-May/055033.html

Given that the asterisk server will be on linux and with the current
growth in its popularity, I expect this to be used along with header
compression and taking care of this problem by asterisk(if possible)
will certainly give it more reasons to be the choice of IP-PBX.

I want to let the asterisk developers know of this so that it can be
taken care of. I had to put in my own hacks to make the IP-ID behave
correctly so that the header compression of the RTP/UDP/IP stream
coming from asterisk(on linux) has no sideeffects.

- Ajay