[Asterisk-Users] Asterisk + BudgeTone (behind NAT)

[Owen Kelso]

I've been following up on my problem, which I previously described as:

> I've concluded that the Netgear router (FVS318) performing the NAT is
> corrupting the outgoing RTP packets.  Traces confirmed that the BudgeTone
> is sending them out with a UDP checksum of 0 but the next hop after the
> Netgear router they are set to a non-zero value (an incorrect one).
> Asterisk is never even seeing the packets because the kernel is
> recognizing them as corrupt and dropping them, hence the recvfrom()
> "Resource temporarily unavailable" errors in rtp.c.

Here is Netgear's response:

---------------------------- Original Message ----------------------------
Subject: RE: Webform contact request [#<removed>]
From:    support at esupport.netgear.com
Date:    Fri, January 23, 2004 7:36 pm
To:      <removed>
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SIP VOIP phones do not work with netgear routers. The router will always
set a value in the checksum.


Regards

<removed>
Netgear Support
support at esupport.netgear.com

Please help us serve you better by clicking here
mailto:support at netgear.com?subject=Feedback_us if you would like to
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Not exactly what I call stellar customer service!

I realize this may not be the best solution -- actually, it's probably not
even a good solution -- but has anyone experimented with using the Linux
SO_NO_CHECK setsockopt() option?  It looks like it could be used to ignore
the checksums for the RTP packets.

Owen