[asterisk-users] QOS for outgoing SIP calls

[Grey Man]

On Wed, Apr 16, 2008 at 11:49 PM, Simon <greminn at gmail.com> wrote:
> Hi There,
>
>  We have our Asterisk box using a external SIP provider for outgoing
>  calls over our DSL line. This seems to be going well... But i do have
>  the ability to set some QOS ports in our linksystem DSL router... Its
>  faily basic, so im wondering if it will help at all...
>
>  We can specify High, Med, Low settings for: FTP, HTTP, Telnet, SMTP
>  and POP3. Plus we have the ability to specify up to 3 ports for the
>  same settings.
>
>  Is this worth doing? If so, what ports should i specifiy?
>

Hi Simon,

You won't be able to get much use of your router's QoS if it can only
set it via port number. By default Asterisk will select a UDP port
somewhere in the range of 10,000 to 20,000 to carry the RTP. The port
selected for the RTP will be different at your end and at your
providers end which means you would need two QoS port rules per call.

You can change the port range your Asterisk server uses for RTP in
rtp.conf but there's probably not a lot of point given you can't
prioritise a big enough range with only 3 rules available. To be of
any practical use for SIP calls you really need to be able to set QoS
by IP address.

Regards,

Greyman.