Network Working Group A. McKenzie Request for Comments #93 BBN Updates RFC's 66, 80 January 1971
Initial Connection Protocol
A review of the Initial Connection Protocol (ICP) first
described in RFC #66 and restated in RFC #80 has revealed an area of ambiguity, which in turn reflects an ambiguity in the Host-Host Protocol Document No. 1. This is the definition of the message sent over the connection from "Server socket #1". In both referenced RFC's, the message is defined as "exactly an even 32 bit number". It is not clear, however, whether this 32 bit number is meant to follow an eight-bit "message data type" code or not, stemming from the fact that the Host-Host Protocol makes provision for such codes but does not seem to absolutely demand them.
Only one implementation of an ICP has been documented in the
NWG literature - that at UCSB (RFC #74). The implementers of this ICP have apparently interpreted the Host-Host Protocol as demanding a message data type code, and therefore do transmit a code of zero.
Steve Crocker indicates (private communication) that the Host-
Host Protocol was intended to require a message data type code. We therefore recommend that RFC numbers 66 and 80 be amended to show that the "even 32 bit number" is preceded by a message data type code of zero (zero is the only code currently defined).
[ This RFC was put into machine readable form for entry ] [ into the online RFC archives by James Thompson 4/97 ]