AT&T uVerse blocking SIP?

Christopher Morrow morrowc.lists at
Tue Jan 27 03:44:33 UTC 2015

I think this is due to the CPE using a particular ALG ... (from
recollection having never been a UVerse customer, but having sat
through a long, long, long set of discussions about the
merits/demerits of sip blocking)

On Mon, Jan 26, 2015 at 10:22 PM, Jared Mauch <jared at> wrote:
> Yes.  If you move to another port, e.g.: 5061 it works fine.
> If you’re running on a Linux based system, you can do this:
> /sbin/iptables -A PREROUTING -t nat -i eth1 -p udp --dport 5061 -j REDIRECT --to-port 5060
> on the host to remap 5061 -> 5060 with no application change.
> - Jared
>> On Jan 26, 2015, at 4:26 PM, Brad Bendy <bb at> wrote:
>> Has anyone seen issues where a end user on uVerse trying to connect to
>> either another provider or AT&T non uVerse (in this case DIA) is having SIP
>> blocked? SIP leaving the uVerse network going to another uVerse DSL account
>> is fine, but it appears soon as it leave the uVerse network all SIP traffic
>> is blocked?
>> It appears others have seen this problem, some say it's a modem issue, some
>> say they are truly blocking it. Ive yet to call uVerse support yet as im
>> guessing ill get no where.
>> Thanks for any insight on this.
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