From the outset the router was specifically chosen to be just the straight forward and basic type.
There are no documented features anywhere, even by any other name, for any form of sip handling.
There is nothing resembling any type sip handling present in the routers configuration interface.
We happen to run another and separate pair of phones for direct IP to IP calling, through another dedicated
series of these same routers. These have been investigated with Wireshark during the set-up and commissioning.
If there were any such, even undocumented, sip facilitated behaviour, it would have already been observed.
From: Users [mailto:[hidden email]] On Behalf Of Newlin, Ben Sent: Friday, 14 April 2017 10:04 PM To: OpenSIPS users mailling list Subject: Re: [OpenSIPS-Users] register phone in same local network as opensips
It doesn’t sound like it has anything to do with the registration. It sounds like your router has some sort of SIP Helper application that is trying to assist by re-writing the ports in the INVITE. Many modern routers come with this functionality enabled by default, even though in my experience it does nothing but break SIP communications.
Take a look at your router documentation for any mention of SIP functionality and disable it.