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Date: Thu, 26 Feb 2004 19:22:39 +0200
From: Nick Strebkov <nick@humgat.org>
To: net@freebsd.org
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Subject: rtp jitter control
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Hi,

I have a kernel-level RTP-poxy and now I need to control a jitter of
incoming RTP stream by caching the last incoming RTP packet and sending
it in case when the next packet is missed or delayed.

RTP-proxy realized as kld module + kernel patch that modify ip_input.c.
Patch adds a hook that process all IPv4 unicast UDP packets. In "my"
packets it change the dest address and call ip_forward() with source
routing simulation.

My solution for task above is to start kernel-level process by
kthread(9) and make buffering for all "my" packets with real sending it
from the started kthread.

Here I have three questions:

1. Is this solution posiible?
2. Do I need some special steps to send a cached packet from my kthread?
3. How to "lose" packet in ip_input()? 

Thanks.

-- 
Nick Strebkov
Public key: http://humgat.org/~nick/pubkey.txt
fpr: 552C 88D6 895B 6E64 F277 D367 8A70 8132 47F5 C1B6