ooh323 q931 signalling problem

Hi all,
I have playing around to find what is the problem with the "fake alerting" and ooh323 channel. I made a test
with GnuGK (2.2.2), Asterisk 1.2.7.1, ooh323 from asterisk-addons-1.2.3. The config is following:

Wellgate FXS GW <------>GNUGK <---------> ASTERISK (ooh323)+SANGOMA FXO<-----------> PSTN

So, what I have found:
1. After Wellgate sends SETUP message it normally receives Call Proceeding, next Alerting and GW starts to
locally generate ring-tone. This should be OK if we have no internetworking with PSTN. When we have
mapping of 2 different protocols there arise issuses like no ring tone or no announcemnets or fake
alerting (like in my case with ooh323). To cope with this the ISDN switch or intermediate GW must send to
originating party a H323 Information Element (IE) called Progress-Indicator which tells the
originating party to wait for the messages (alerting, busy, "The number you have dialed is no longer in
service...", etc.) in-band instead of generating them locally.
More info on this can be found here:
http://www.cisco.com/en/US/tech/tk1077/technologies_tech_note09186a0080094c33.shtml

So, I think the ooh323 must send PI=8 in Alerting message(means: In-band information or an appropriate
pattern is now available) and opens RTP channel to wait for in-band signalling messages from the PSTN.
This should fix the fake ringing and the real alerting tone should be heard once the PSTN rings.
I found this OK with SIP.

2. I think currently ooh323 doesn't support "early media", i.e doesn't open the RTP channel after
receiving alerting and doesn't support faststart in messages before CONNECT.  In this way if I put the PI=8
in H.323 Alerting message I don't hear alerting tone because the channel is not opened from Asterisk side
and the signalling messages can't pass-through.
I think these features are very important for H323 channel because most of the time we deal with PSTN
networks, either for terminating or originating and no fake signalling is acceptable.

Hope to have answered some of the questions from the other users. 
I will appreciate if someone help me in coding these. I think it is not too much work!

Thanks!
mortex

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