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Ethereal-dev: Re: [Ethereal-dev] First cut at H.450 dissector

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From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Tue, 23 Sep 2003 23:57:16 -0700
On Wed, Sep 24, 2003 at 09:31:14AM +0800, Graeme Reid wrote:
> Attached are two samples containing H.450 packets.
> 
> The file BlindTransfer contains a blind transfer with a return error,
> followed by a successful blind transfer with a return result.

It looks as if the invokeId in frame 17 is 02 90 5c; if the 02 is a
length determinant, then it says the value is 2 bytes long, and the
bytes are 90 5c

0x905c has its uppermost bit set, so that's a negative number.  If the
intent was to encode 36956 (as I suspect is the case, given that the
invokeId in frame 16 was 36956), then either

	1) it should've been encoded as 03 00 90 5c, so that the
	   uppermost bit was 0;

	2) the H.450 spec ASN.1 specifications from the ITU site (URL in
	   my previous message) are incorrect;

	3) I've misread some spec somewhere (either X.691 or the H.450
	   spec).