Forcing SIP trunk matching order?

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I have a bunch of different customers on an Asterisk Box (the PBX).
This Asterisk Box is behind another Asterisk box that provides a PSTN
Up to this point I’ve been using IAX between the 2 Asterisk boxes, but
I would like to use SIP instead.
After doing some testing I have the following issue.

If customer A calls customer B, but the call goes out through the PSTN
and comes back in, the call is rejected at the PBX because it wants
I can guess that this must be because it matches the “To” address to
the friend SIP trunk that provides registration for the phone.
(All phones are setup as type=friend, host=dynamic). Is there any way
to force matching against the peer SIP trunk to PSTN so as to not
require authentication for calls
coming in from the PSTN server?


3 thoughts on - Forcing SIP trunk matching order?

  • 28 jun 2012 kl. 23:25 skrev Duncan Turnbull:


    This is probably because you are using phone numbers as names of devices with type=friend in sip.conf.
    That’s generally a bad idea.

    The SIP channel matches an incoming call this way:

    1. Take the From: user name and match with the list of type=user and type=friend
    2. Take the sender’s IP and port and match with the list of peers
    3. Send the call to the context defined in the [general] section of sip conf

    In Asterisk 1.4 and hopefully 1.8 the last peer in sip.conf will match first. In 1.8 the internal strcutures
    was changed, but I hope that this functionality was retained. We had a dicussion about it, but I personally
    haven’t tested the result. One needs to know the matching order, so if 1.8 doesn’t behave that way, we need
    to fix it.

    The recommended way is to NOT use anything that likely will end up as a caller ID as names
    of devices in sip.conf. The name is whatever you have within square brackets above definitions
    of type=friend or type=user. The username= option is another option, not the name of the device.

    The quick way to solve your problems is to stop using type=friend and start using type=peer


  • Hi Ollie,

    You are correct, I do have callerID-type names as accounts in sip.conf. The hosts are set to dynamic. Is this a problem with type=peer?

    Would the deny/allow suggestion posted earlier also work with type=fiend?


    — James

  • 11 jul 2012 kl. 00:26 skrev James Lamanna:

    As stated above, peers only match on IP+port for incoming calls.

    Deny/allow is a different thing and doesn’t really affect matching. It is applied AFTER matching, not during or before.