SARK V4.0.0 siptrunks
Contents
Introduction
You will often find it necessary to talk to downstream PBX systems or gateways; either inside your company or if you are running a boutique ITSP service using SARK. Here is a set-up guide for such trunks.
N.B.
- This information does NOT apply to regular SIP trunks to upstream carriers.
Registered Trunks (recommended)
Unless you have a good reason not to, you should require the downstream PBX to register with you. If you wish to support multiple trunks to the downstream PBX; usually for accounting purposes or to avoid port forwarding on the downstream router, then you MUST use this method.
On your Upstream PBX
Create each trunk on your upstream PBX as follows
type=peer context=internal host=dynamic username=someuser secret=somesecret qualify=yes canreinvite=no insecure=port,invite disallow=all allow=alaw allow=ulaw
N.B.
- In SARK you must also set the peername (in the separate peername box) to the SAME value as the trunkname
On the Downstream PBX or gateway
Create each trunk on the downstream PBX as follows
type=peer
host={ip address}
qualify=yes
username=someuser
secret=somesecret
canreinvite=no
insecure=port,invite
disallow=all
allow=alaw
allow=ulaw
nat=yes
If this a SARK box then check registration=YES when creating the trunk. Otherwise, create a registration entry as follows
register => someuser:somesecret@{ip address}/someuser
Direct Connect
You can set up a "direct connect" with or without login credentials. This kind of trunk is often used in conjunction with SIP gateways or known, friendly endpoints.
N.B.
- You MUST ensure you restrict access in the SARK firewall or your perimeter firewall if you wish to run without credentials. Otherwise you will, in effect, have an open SIP proxy and anyone will be able to send calls through your PBX.
- You should not run multiple direct connect trunks to the same endpoint or your call accounting will likely be incorrect
On your Upstream PBX
All that is needed is a general sip trunk with the asterisk peer set as follows
type=peer
context=internal
host={ip addr}
qualify=yes
canreinvite=no
insecure=port,invite
disallow=all
allow=alaw
allow=ulaw
On the Downstream PBX or gateway
Create each trunk on the downstream PBX as follows. This is slightly different to the upstream example above.
type=peer
host={ip addr}
qualify=yes
canreinvite=no
insecure=port,invite
disallow=all
allow=alaw
allow=ulaw
N.B.
- You will also need to set up a port forward in your firewall for 5060 and 10000-20000 UDP. For this reason it is recommended that you use registration wherever possible because it does not normally require any port forwarding.
