Network Working Group R. Braden
Request for Comments: 3109 ISI
Category: Informational R. Bush
Request to Move STD 39 to Historic Status
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright (C) The Internet Society (2001). All Rights Reserved.
This memo changes the status of STD 39, BBN Report 1822,
"Specification of the Interconnection of a Host and an IMP", from
Standard to Historic.
The Internet design grew out of the pioneering packet-switched
network called the ARPAnet. The ARPAnet was a mostly-US national
network built of mini-computer packet switches, called Interface
Message Processors (IMPs), that were linked by 56kbps leased
telephone lines. The IMPs were designed and built by Bolt, Beranek,
and Neumann (BBN) under contract with ARPA, beginning in 1968. One
of BBN's first tasks was to define the standard hardware interface
between a host and a colocated IMP. This interface was described in
BBN Report 1822 [BBN1822], which was a bible for the administrators
of the many different hosts that connected to the ARPAnet.
The BBN Report 1822 host/IMP hardware interface was bit-serial and
asynchronous. In 1968, the 8-bit byte had not yet been adopted as an
industry standard, so the interface had to cope with word-based
machines with arbitrary word length -- some common word lengths were
8, 12, 16, 24, 36, and 60, but there were others. From the software
viewpoint, Report 1822 defined what would today be called the link-
layer access protocol for the ARPAnet.