SARK V4.0.0 Gamma IPDC
Contents
Introduction
Gamma IPDC trunks are quite popular in the UK so here is a brief guide to setting up your sark box to work with them.
Create the trunk and DDI entries
The IPDC trunk is an IP authorized peer to peer connect with no authorization checking so the basic set-up is very simple. Create a trunk with no registration so that it looks like this in the asterisk tab of the SARK trunk
type=peer host=88.215.63.169 ; gamma ip address qualify=yes insecure=port,invite disallow=all allow=alaw allow=ulaw
If you wish you can set a fromdomain with your IP address or you can set the external ip in globals; one or the other.
Now, create your DDI's in inbound routing and you're done. Gamma presents 11 digits in the DDI.
N.B. Don't forget to forward 5060 and 10000-20000(UDP) from your perimeter firewall to SARK and also ensure that you allow 5060,10000-20000 (UDP) in the SARK firewall from the Gamma IP (AND ONLY the Gamma IP).
Session timers
Gamma will expire the session timer after 30 minutes which can cause calls to drop after that time. To prevent this add the following line to /etc/asterisk/sark_customer_sip_header.conf in the asterisk section of the browser app.
session-timers=refuse
Caller ID on send
There seems to be some confusion with this. In the past we've always had to present a full E164 number preceded by a + sign in the cli (e.g. +441924918076) however, it also seems to work with regular numbers if you send it in the P-Asserted-ID header. To do this turn on PA-ID in sark_sip_header.conf (it is on by default in later SARK releases)
sendrpid=pai
Withhold Caller ID on send
This can be done via P-Asserted-ID. To set it up you need to create a custom outbound route. Let's say you want to withhold the CLID when your caller prefixes a call with 141.
create a custom app (call it whatever you like) and give it a span of internal. Copy and paste this code into it
exten => _1410XXX.,1, NoOp
same => n,SipAddHeader(P-Asserted-Identity:sip:anonymous@anonymous.invalid)
same => n,SipAddHeader(Privacy: id)
same => n,Set(CALLERID(num)=Anonymous)
same => n,Set(CALLERID(name)=Anonymous)
same => n,agi(sarkhpe,OutCos,${EXTEN:1}) same => n,Hangup
Finally, remove the 141 in the gamma trunk by creating a transformation mask of 141:
That's it. Now if you prefix your dial with 141, the CLI will be withheld.
