RFC 48 (rfc48) - Page 1 of 18
Possible protocol plateau
Alternative Format: Original Text Document
Network Working Group J. Postel
Request for Comments: 48 S. Crocker
UCLA
April 21, 1970
A Possible Protocol Plateau
I. Introduction
We have been engaged in two activities since the network meeting of
March 17, 1970 and, as promised, are reporting our results.
First, we have considered the various modifications suggested from
all quarters and have formed preferences about each of these. In
Section II we give our preferences on each issue, together with our
reasoning.
Second, we have tried to formalize the protocol and algorithms for
the NCP, we attempted to do this with very little specification of a
particular implementation. Our attempts to date have been seriously
incomplete but have led to a better understanding. We include here,
only a brief sketch of the structure of the NCP. Section III gives
our assumptions about the environment of the NCP and in Section IV
the components of the NCP are described.
II. Issues and Preferences
In this section we try to present each of the several questions which
have been raised in recent NWG/RFC's and in private conversations,
and for each issue, we suggest an answer or policy. In many cases,
good ideas are rejected because in our estimation they should be
incorporated at a different level.
A. Double Padding
As BBN report #1822 explains, the Imp side of the Host-to-Imp
interface concatenates a 1 followed by zero or more 0's to fill
out a message to an Imp word boundary and yet preserve the
message length. Furthermore, the Host side of the Imp-to-Host
interface extends a message with 0's to fill out the message to
a Host word boundary.
BBN's mechanism works fine if the sending Host wants to send an
integral number of words, or if the sending Host's hardware is
capable of sending partial words. However, in the event that
Postel & Crocker