[asterisk-users] Sonicwall potentially causing long ping times to SIP phones

[Kristian Kielhofner]

On 10/23/08, Bruce Komito <brucek at bagel.com> wrote:
> We've had LOTS of problems with Sonicwalls doing bad things to SIP and RTP
>  connections.  I've seen the delay thing, as well as the Sonicwall throwing
>  away entries from the ARP table because of inactivity.  I've also seen
>  sporadic, intermittent problems with transfer from one phone to another.
>  I have no doubt that a new, properly configured Sonicwall can be made to
>  function properly in a VoIP environment, but we are not Sonicwall experts,
>  nor are many of the purported experts.  In every case where we've had
>  problems with VoIP behind a Sonicwall, the problems ALL disappear when we
>  put the phones on a LAN segment that does not pass through the Sonicwall.
>  So, now that's our going in position.  If it works, great, but if it
>  doesn't, our solution is to take the Sonicwall out of the picture.
>
>  My $.02 .
>
>  Bruce Komito
>  WPTI Telecom
>  (775) 236-5815
>

I wouldn't single out SonicWalls when it comes to breaking SIP traffic.

Most of the "anything but simple PAT" devices I've seen that implement
any SIP specific fixups usually end up breaking something along the
line.  Unless the product is from a company where SIP is their core
competency (like Ingate, or /maybe/ Cisco) it's best to stay away
and/or disable the SIP specific fixups wherever possible.

I'm looking forward to the day when SIP-TLS is the norm and these
devices have no idea what kind of traffic is flowing through them!

-- 
Kristian Kielhofner
http://blog.krisk.org
http://www.submityoursip.com
http://www.astlinux.org
http://www.star2star.com