Josh
All call signaling is via TCP. Although there is support for transmission over UDP in the standard AFAIK no-one has implemented it.
There are pro’s and con’s either way
TCP is reliable and as you say you can have large message sizes however as it’s a persistent connection and can and does break (for instance with NAT) and calls do drop. Just finished a major commit to resolve that issue in the h323plus stack and if the connection does break then there is an attempt to reconnect and the call does not drop. UDP signaling guys have been throwing that around for years to justify using UDP for signaling.
You can add custom messages via the H460_Feature interface. There is a H460 factory loader subsystem which loads your derived class into the signaling. The H460_Feature class contains message overrides for each signaling message. You would want to look at deriving you class from H460_FeatureOID or H460_FeatureNonStd. To get an idea what to do, have a look at H460_FeatureStd19 it has most of the structure you need there.
Simon
From: h323plus-bounces@lists.packetizer.com [mailto:h323plus-bounces@lists.packetizer.com] On Behalf Of J.C Mercier
Sent: 11 April 2012 15:06
To: h323plus
Subject: [h323plus] H323plus support for UDP signalling
Hi all,
Just curious, does H323plus support signalling via UDP? If not, what are the advantages of using TCP signalling over UDP, aside from it being reliable (considering UDP packets doesn't exceed the UDP size limit for each message sent, if it's even possible with H323 messages) ?
Another question, is it possible to include generic messages within the signalling messages (setup, process, alert, connect, facility etc) just as we can with the h.245 OLC messages?
Thanks in advance for your help and suggestions.
Josh C. M