[asterisk-users] [asterisk13] Multiple transport objects of same protocol in pjsip.conf

O. Hartmann ohartmann at walstatt.org
Sat Jul 29 12:55:09 CDT 2017


Our Asterisk 13 PBX (on network, bound to is behind
a NAT, acting as a client to our ITSPs SIP server. But also, this Asterisk is server for
various VoIP telephones. 

Acoording to Asterisk's wiki, the transport section of pjsip.conf is configured as

; Transport via UDP
type=                           transport
protocol=                       udp
external_media_address=         ddns.gdr
external_signaling_address=     ddns.gdr

The VoIP phones are also residing on network, bu they are separated and
strictly prohibited by firewall rules to act with the outer net. The Asterisk PBX is
acting as the transition point between our VoIP phones and the ITSPs SIP server.

So, my understanding is that for NAT, the transport is recommended to be configured as
shown above. But what is about the transport with the phones "inside"?

I'm new to Asterisk, and from the "naiv" understanding of what I extracted from the
sparse documentation on that subject, for each endpoint associated with a phone, I need
transport. The protocol used by the phones is UDP, but no NAT. So, I did create a new
transport section, like

type=                           transport
protocol=                       udp

This results immediately in an error due to the bind= attribute. Asterisk bails out at
havind the address already in use. In fact, it is the trunk/endpoint consuming the, and since the VoIP phones are all in, this results
obviously in an error. This is surprising me :-(

How to deal with this without adding more network complexity like routing (by putting the
phones into a subnet or other network)?

Kind regards,

O. Hartmann
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 313 bytes
Desc: OpenPGP digital signature
URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20170729/bb0b3798/attachment.pgp>

More information about the asterisk-users mailing list