Message-ID numbers
David C. Walden · 1973
It has been noted that the IMP message format (specified in BBN Report 1822) constrains network users to low throughputs if messages are to be uniquely identified via the link number.We have recently implemented a change in the IMP/Host protocol which alleviates this difficulty.The link field in the IMP/Host and Host/IMP leaders has been extended to the right by four bits (in other words, it now uses bits 17 to 28 of the leader), and the name of the link field has been changed to the _message-id field_.We expect this field to be used to uniquely identify messages between the IMPs and the Hosts.All 12 bits in the message-id will be returned to the Host in RFNMs, INCOMPLETE TRANSMISSIONs, etc.Note that no ordering is implied by the use of the message-id field.