[asterisk-users] Make outgoing calls through BroadWorks/BroadSoft SIP gateway from Asterisk

[James Stocks]

I've been given a SIP hard phone pre-configured to work with another party's BroadWorks system.  I want to use my Asterisk system to connect to this SIP service rather than the handset I've been given.  I have extracted the authentication details from the phone and have successfully registered Asterisk with the gateway (incoming calls work fine) using a line like this in sip.conf:

register => 441000123123 at auth.realm:password:authuser at nnn.nnn.nnn.nnn/441000123123

Outgoing calls are proving to be more challenging.  I have this so far:

[441000123123]
callerid="My Name" <441000123123>
type=peer
host=nnn.nnn.nnn.nnn
auth=authuser
realm=auth.realm
fromuser= 441000123123
secret=password
insecure=invite
context=from-sip
nat=yes
qualify=no
canreinvite=no
allow=all

The main part I'm confused about is that in most examples I've seen, the username and authname are the same value, whereas in this case we seem to have:

A username (the phone number)
An auth name (a different value)
An auth realm
A SIP realm (different value to auth realm)
A password
A gateway host

When I place a call with Dial(SIP/441000123123/somenumber), I get a 403 response from the gateway.  Looking at a packet dump, I can see that Asterisk is not attempting to authenticate.  On the other hand, REGISTER requests do authenticate successfully - I can see the digest authentication taking place in tcpdump.

I have observed successful outgoing calls from the hard phone using tcpdump and I can see the phone using digest like so:

Authorization: DIGEST username="authuser", realm="BroadWorks", nonce="BroadWorksASHORTHASH", qop=auth, cnonce="ASHORTHASH", nc=00000001, uri="sip:number at auth.realm:5060;user=phone", response="ALONGERHASH", algorithm=MD5 

What is the correct configuration to use - how do I get Asterisk to successfully authenticate outgoing calls?

Many thanks,
James.