[Asterisk-Users] GR303

[Rich Adamson]

> 
> Anybody out there using GR303?  Latest grumblings on the list are from 
> last spring.  I'd like to use Asterisk as a concentrator/DLC speaking 
> 303 to a 5E.  Threads from awhile back mentioned support only for 
> Asterisk spekaing to a concentrator, rather than acting as one itself, 
> but the gr303fxsks_cpe signalling mentioned in zapata.conf gave me some 
> hope.
> 
> If anybody has succeded in either regard, I'd like to hear about it.

I'm within a couple of weeks of attempting this by interfacing asterisk
with a Siemens CO switch via gr303. All the physical components are in 
place, just need to find some time to config asterisk, etc. This CO
switch already has something like 30 remote concentrators (from another
manufacturer) in solid production, therefore I have little concern with
the Siemens gr303 implementation; the asterisk code is unknown at this
time.

One of the Digium employees recently completed a test involving looping
two T1's on asterisk (one interface config'ed as the network side and
the other interface config'ed as a concentrator). He was able to complete
calls via the loop which only suggests that base gr303 support for both
is in place. The asterisk code to interface with a remote concentrator
has been in place for over a year suggesting a rather solid understanding
of the protocol requirements. However, No one knows for sure whether 
asterisk's gr303 support is or is not complete enough to interface with 
CO switches, but there is also no known concerns (or even tests) either.

It is known the asterisk gr303 support does _not_ include any maintenance
channel, therefore definitions within the CO switch (or concentrator) and
definitions within asterisk have to be manually mapped and maintained.
Other day to day maintenance functions (eg, remote deactivation functions)
are obviously not supported either. Not sure if that will be any sort of
issue or not, or even how a CO switch reacts when it receives no response
from asterisk.

I'm not a programmer, but its my understanding (which could be wrong) that
gr303 is a rather simple protocol (in relative terms). Its also my
understanding that Mark is one of the primary developers of the code,
therefore if there are compatibility issues uncovered, identifying and
correcting those issues may be time consuming due to demands on his time.

Rich