Version = 5.6.0-dev0

We are seeking help to resolve an issue with registering devices to 3CX (All 3CX servers, have tried 8 different ones) . all the auth info including passwords etc are identical on the 3cx servers.

We use Kamailio to register mobile sim cards to 3^rd party sip servers i.e. 3CX.

We send the normal Username, server addresses and auth details but are experiencing failures with 3CX rejecting the registration and return Proxy Auth failure 407. We have noticed in the pcaps from both sides that the expire value is changing from 180 as an example to 0.

As an example In the uac reg_dump the values are :

l_uuid: +447529135850
        l_username: +447529135850
        l_domain: sbc-mt.asim.apalo.io;transport=udp
        r_username: 1001
        r_domain: egte.3cx.uk
        realm: <null string>
        auth_username: FdlHDC1IvA
        auth_password: extracted
        auth_ha1: none
        auth_proxy: sip:egte.3cx.uk:5060
        expires: 60
        flags: 0
        diff_expires: -1738853736
        timer_expires: 0
        reg_init: 1738850836
        reg_delay: 0
        contact_addr: k01.asim.apalo.io;transport=tcp
        socket: <null string>

Looking forward to hearing from you.

Many thanks

Tony Ford