Simple Internet Protocol Plus

Document Charter Simple Internet Protocol Plus WG (sipp) Snapshot
Title Simple Internet Protocol Plus
Last updated 1994-11-18
State Approved
WG State Concluded
IESG Responsible AD Allison Mankin
Charter Edit AD (None)
Send notices to (None)


Simple Internet Protocol Plus (SIPP) is one of the candidates being
considered in the Internet Engineering Task Force (IETF) for the next
version of the Internet Protocol (IP).  The current version of IP is
usually referred to as IPv4.  The purpose of the working group is to
finalize the SIPP and IPAE specifications, foster the early development
and experimentation of this protocol, and to work toward having SIPP
selected as the IETF's IPng.

SIPP is a new version of IP which is designed to be an evolutionary step
from IPv4.  It is a natural increment to IPv4.  It can be installed as a
normal software upgrade in internet devices and is interoperable with the
current IPv4.  Its deployment strategy is designed to not have any
``flag'' days.  SIPP is designed to run well on high performance networks
(e.g., ATM) and at the same time is still efficient for low bandwidth
networks (e.g., wireless).  In addition, it provides a platform for new
internet functionality that will be required in the near future.


The SIPP Working Group represents the evolution and merger of three
different IETF working groups focused on developing an IPng.  The first
was called IP Address Encapsulation (IPAE) and was chaired by Dave
Crocker and Robert Hinden.  It proposed extensions to IPv4 which would
carry larger addresses. Much of its work was focused on developing
transition mechanisms.  Somewhat later Steve Deering proposed a new
protocol evolved from IPv4 called the Simple Internet Protocol (SIP).  A
working group was formed to work on this proposal which was chaired by
Steve Deering and Christian Huitema.  SIP had 64-bit addresses, a
simplified header, and options in separate extension headers.  After
lengthy interaction between the two working groups, and the realization
that IPAE and SIP had a number of common elements and the transition
mechanisms developed for IPAE would apply to SIP, the groups decided to
merge and concentrate their efforts.  The chairs of the new SIP Working
Group were Steve Deering and Robert Hinden.  In parallel to SIP, Paul
Francis (formerly Paul Tsuchiya) had founded a working group to develop
the ``P'' Internet Protocol (PIP).  PIP was a new Internet Protocol based
on a new architecture.  The motivation behind PIP was that the
opportunity for introducing a new Internet Protocol does not come very
often and given that opportunity important new features should be
introduced.  PIP supported variable length addressing in 16-bit units,
separation of addresses from identifiers, support for provider selection,
mobility, and efficient forwarding.  It included a transition scheme
similar to IPAE.  After considerable discussion among the leaders of the
PIP and SIP Working Groups, they came to realize that the advanced
features in PIP could be accomplished in SIP without changing the base
SIP protocol, as well as keeping the IPAE transition mechanisms.  In
essence, it was possible to keep the best features of each protocol.
Based on this, the groups decided to merge their efforts.  The new
protocol was called Simple Internet Protocol Plus (SIPP).