Pete,

Although it appears in a section dealing primarily with Fast Connect and H.245 Tunneling, the following requirement is not qualified in any way. Moreover, the sentences that precede it talk about _initiating_ a separate H.245 channel, not just _switching_ to a separate channel, so I don't believe this requirement is dependent on there first being a tunneled H.245 channel or the use of Fast Connect.

8.2.3/H.323v4: "An endpoint receiving a Facility message with a facilityReason of startH245 which has not already independently initiated the separate H.245 channel shall open the H.245 channel using the h245Address specified."

Therefore, in answer to your questions,

1. yes, Facility with reason=startH245 is appropriate at any time, and 2. yes, an EP is required to open an H.245 channel as specified in 8.2.3.

Paul Long ipDialog, Inc.

-----Original Message----- From: Mailing list for parties associated with ITU-T Study Group 16 [mailto:ITU-SG16@echo.jf.INTEL.COM]On Behalf Of Peter Price Sent: Friday, January 04, 2002 3:32 AM To: ITU-SG16@echo.jf.INTEL.COM Subject: Facilty Message, reason StartH245

All,

I need a little help with interpretation...

I believe that the receipt of a Facility message with reason "StartH245" means that the receiving endpoint SHALL open an H245 channel to the sender at the supplied transport address. However, I can't find where it specifies the SHALL part of this statement in the standards.

The only references I can find to startH245 are (H323/8.2.3) related to Fast Connect and tunnelling (H.245/7.4.1) which is actually about when the reason code is NOT StartH245

So the questions are:

1) Is it appropriate to use Facility (startH245) outside Fast Connect or Tunnelling (for instance the called endpoint trying to force the equivalent of Early H245)

2) Is it really mandatory for the receiving endpoint to open the H245 channel - if so where does it stipulate this in the standards.

Thanks

Pete Price Vegastream Ltd