Subject: RE: Mode Property for a Termination

From: Dave Sclarsky <[email-masked]>
Date: Tue, 24 Apr 2001 10:19:10 -0400

Sarju,

Yes, the example call flow isn't perfect (e.g. in step 17, the reply from
MGC uses NULL context even though the transaction used context 5000).

As to your question about mode, well, in the Megaco model, it is not the
'terminating exchange' (remote MG?) that plays ringback.  Look at the Modify
for A4444 in step 16.  Here the MGC tells the caller's MG to play ringback
locally, using the signal cg/rt.  Here both physical terminations are
initially set to sendReceive.  The ephemeral on the calling side is set to
receive, and the ephemeral on the called side is set to sendReceive.  The
MGC doesn't set the calling side's ephemeral to sendReceive until the called
party goes off hook.

One other important point is that signals are NOT affected by Mode.  The MGC
could have left the calling physical termination as inactive and still
played ringback (or busy, or whatever)!

DaveS.
RadiSys Corporation [formerly S-Link Corp.] 

-----Original Message-----
From: Sarju Garg [mailto:[email-masked]]
Sent: Tuesday, April 24, 2001 7:38 AM
To: [email-masked]
Subject: Mode Property for a Termination

Hi Lists,

I have a query related to the call flow (Appendix A section A.1.2 step 12)
shown in the H.248 document. Why is the mode of the termination A4444 not
set to sendonly? Since the default state is inactive, then how will the
caller hear the RBT applied by the terminating exchange (if mode!=sendonly)?
Also mode in step 3 is set to send/recv. Why is that so? We do not need to
set mode now. Let it be inactive and change mode only in step 12 to sendonly
TIA
Sarju