SIPGATE

Sipgate also provides SIP service to its customer with no line rental fees.

It also uses the SIP Express Router as a front-end proxy like CallUK?/Nildram. Their registration system is rather fussy and unreliable, but otherwise it more or less works as advertised. I had some problems with it initially, but they ended up being problems with lack of proper VAD support in asterisk and the clients.

Configuration for Asterisk

The Configuration for Asterisk when using NAT is:

; XXXXXX - sipgate extension as 
; in the registration email
; YYYYYY - password
register => XXXXXX:YYYYY@sipgate.co.uk

[sipgate.co.uk]
; section for originating calls
secret=YYYYYYY
username=XXXXXXX
outgoingproxy=sipgate.co.uk
fromuser=XXXXXXX  ; this is essential to make outgoing calls work
                      ; if unset asterisk will forward the extension ID in the SIP INVITE
                      ; and the call will fail
fromdomain=sipgate.co.uk
host=sipgate.co.uk
peer context=from-sip 
canreinvite=no 
disallow=all 
allow=ulaw,alaw ; essential if you want DTMF working
; allow=g729,ulaw,alaw - have not tested rfc2833 DTMF yet
dtmfmode=inband 
nat=yes 
type=peer                      
insecure = very 

[sipgate.co.uk]
; section for receiving calls
secret=YYYYYYY
username=XXXXXXX                 
fromdomain=sipgate.co.uk
host=sipgate.co.uk
peer context=from-sip 
canreinvite=no 
disallow=all 
allow=ulaw,alaw ; essential if you want DTMF working
; allow=g729,ulaw,alaw - have not tested RFC DTMF yet
dtmfmode=inband 
nat=yes 
type=user

Setup Notes

The authentication on the SER at sipgate is sometimes rather slow. As a result it is a good idea to raise the register expiry to the maximum value to avoid frequent reregistration (asterisk default is only 120s).

The SER at sipgate is configured to sent NULL back on the SIP connection if it detects NAT. As a result the connection is kept alive without any problems so frequent reregistration is not necessary.

-- AntonIvanov? - 18 Nov 2008