Considering the issue further, a length of one octet is definitely wrong (it must be 2 octets for an empty Cause IE) and has to be fixed (original mail is attached below).
Ernst Horvath Siemens AG
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-----Ursprüngliche Nachricht----- Von: Horvath Ernst Gesendet am: Mittwoch, 29. September 1999 11:15 An: ITU-SG16@mailbag.cps.intel.com Betreff: H.225.0 - Length of Cause IE in Release Complete message
Dear Mr. Freundlich,
In H.225.0V3, section 7.3.9, the Cause IE is marked CM, and the associated note implies that this IE can actually be included (see table 12/H.225.0). But the length of one octet allows only an empty IE, which is meaningless.
Is this an error or intentional? In any case it is confusing and should be fixed at the Red Bank meeting.
Ernst Horvath Siemens AG