[VoiceOps] PSTN connection to SONUS
abalashov at evaristesys.com
Thu Nov 12 12:07:04 EST 2009
"Supports" SS7 is a nebulous notion. SS7 entails a pretty large
protocol stack and capabilities set.
Asterisk-ss7 supports basic ISUP and it mostly works, so it's a
potentially functional replacement for PRI in places where telcos
prefer private SS7 to PRI for access.
Beyond that particular application, it is mostly useless from a
service provider or carrier standpoint.
It does not support TCAP at all, so no LNP/CNAM/LIDB.
Secondly, it does not support any outboard media gateway control
protocols - no MGCP or H.248/MEGACO. So, you can't use an Asterisk
signaling agent to drive a horizontally scalable farm of independent
media gateways; as with everything else, Asterisk integrates the
signaling and bearer plane into one unitary process and one host. The
signaling link must be physically associated with the bearer trunks.
In practice, this means that the inter-machine trunk group size you
can signal is limited to how many T1s can practically go into a PC
host running Asterisk; to me, that's 4, though some people think you
can put 5-8 T1s into a PC with dual quad-port cards.
It might be good for connecting to a Sonus, but not if you want to
signal more than a handful of T1s. I strongly suggest you follow the
advice to use PRI instead, as it's also much better supported and
Carlos Alvarez wrote:
> On 11/12/09 7:55 AM, Jason Vanick wrote:
>> Actually you'll probably want to use a PRI config
>> ISUP is used if you're connecting to a switch that requires SS7
>> as far as I'm aware, asterisk doesn't support SS7.
> Asterisk does have partial support for SS7. Last time I looked into it
> the major functions were there, but not all of them. However there have
> been Asterisk servers in production using SS7 for at least a year and a
> half, possibly more.
> VoiceOps mailing list
> VoiceOps at voiceops.org
Alex Balashov - Principal
Web : http://www.evaristesys.com/
Tel : (+1) (678) 954-0670
Direct : (+1) (678) 954-0671
More information about the VoiceOps