Situation: An MRPDU is being parsed. At this point, a VectorAttribute has just been parsed and the next two bytes in the packet are 0x00 0x01. According to the grammar, we would expect another VectorAttribute or an EndMark at this point. Given that the next byte is 0x00, it appears to be an EndMark followed by another message with AttributeType 0x01. However, these same bytes could be interpreted as another VectorAttribute. In this case, the VectorHeader for this VectorAttribute would be 0x0001 which indicates that LeaveAll is clear and NumberOfValues is 1. Specifically, any time that the second, third, etc VectorAttribute in an AttributeList has LeaveAll clear and (NumberOfValues < 256), the sequence of bytes appears to not be distinguishable from an EndMark followed by an AttributeType. How should these byte sequences be interpreted in these cases?
This is an error in the PDU specification. The correct specification of EndMark is SHORT (i.e., a 16-bit field, value 0). 802.1 has raised a PAR for a corrigendum to correct the error. This response was approved by 802.1 at its July 2007 plenary meeting.
Pages copyright © Institute of Electrical and Electronics Engineers, Inc. Please read the rules on Confidentiality Statements and Copyright Notices on Communications. Information on Privacy and opting out of cookies is available. If you have any comments on these pages, please send them to me.
