[LARTC] QoS and VoIP

[LARTC] QoS and VoIP

[Alessandro Oliveira Ungaro]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hi all,

I made some filters on tc to match the VoIP traffic based on RTP packet
RFC 1889.

The only patern I found was the rtp version and the payload type wich
identify the codec. The u32 rules are:

- - match ip protocol 0x11 0xff -> UDP
- - match u8 0x80 0xc0 at 28 -> RTP version 2 (two fists bits '10' of the
byte)
- - match u8 0x61 0x7f at 29 -> Codec number 97 (seven bits of the byte
without the first bit)

This with a iptables marking the packet with dport and sport > 1024 work
fine. But if I have more codecs I need more filter rules.

Some idea to match better?

Thanks.

x-arnie
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.7 (GNU/Linux)

iD8DBQFCMaWASp5uKJPliCsRAh3HAJwIGeFfWcUp+xu4/Hvdsnm2YIdCzACfW2wt
j3HJghFYfZPlWVshRR8cx9YŽwq
-----END PGP SIGNATURE-----
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc

Re: [LARTC] QoS and VoIP

[Ed Wildgoose]

Alessandro Oliveira Ungaro wrote:

>
> I made some filters on tc to match the VoIP traffic based on RTP packet
> RFC 1889.
>
> The only patern I found was the rtp version and the payload type wich
> identify the codec. The u32 rules are:


Interesting question! 

This is probably a good questino to take to the l7 (layer 7) mailing 
list as well.  See if they have some stuff already...

Sorry, no practical better suggestions from me though...

Ed W
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc