2.2.1.2 Message ID Structure

A Message ID structure uniquely identifies a message in the context of a logon to a Store object. The Message ID structure is serialized compactly in the context of a ROP, such as the RopOpenMessage ROP ([MS-OXCROPS] section 2.2.6.1), where the Store object context is already established. It is an 8-byte structure.

0	1	2	3	4	5	6	7	8	9	1 0	1	2	3	4	5	6	7	8	9	2 0	1	2	3	4	5	6	7	8	9	3 0	1
ReplicaId																GlobalCounter
...

ReplicaId (2 bytes):  An unsigned integer identifying a Store object.

GlobalCounter (6 bytes):  An unsigned integer identifying the message within its Store object.