RFC 1055 (rfc1055) - Page 1 of 6


Nonstandard for transmission of IP datagrams over serial lines: SLIP



Alternative Format: Original Text Document



Network Working Group                                          J. Romkey
Request for Comments: 1055                                     June l988

 A NONSTANDARD FOR TRANSMISSION OF IP DATAGRAMS OVER SERIAL LINES: SLIP

INTRODUCTION

   The TCP/IP protocol family runs over a variety of network media:
   IEEE 802.3 (ethernet) and 802.5 (token ring) LAN's, X.25 lines,
   satellite links, and serial lines.  There are standard encapsulations
   for IP packets defined for many of these networks, but there is no
   standard for serial lines.  SLIP, Serial Line IP, is a currently a de
   facto standard, commonly used for point-to-point serial connections
   running TCP/IP.  It is not an Internet standard.  Distribution of
   this memo is unlimited.

HISTORY

   SLIP has its origins in the 3COM UNET TCP/IP implementation from the
   early 1980's.  It is merely a packet framing protocol: SLIP defines a
   sequence of characters that frame IP packets on a serial line, and
   nothing more. It provides no addressing, packet type identification,
   error detection/correction or compression mechanisms.  Because the
   protocol does so little, though, it is usually very easy to
   implement.

   Around 1984, Rick Adams implemented SLIP for 4.2 Berkeley Unix and
   Sun Microsystems workstations and released it to the world.  It
   quickly caught on as an easy reliable way to connect TCP/IP hosts and
   routers with serial lines.

   SLIP is commonly used on dedicated serial links and sometimes for
   dialup purposes, and is usually used with line speeds between 1200bps
   and 19.2Kbps.  It is useful for allowing mixes of hosts and routers
   to communicate with one another (host-host, host-router and router-
   router are all common SLIP network configurations).

AVAILABILITY

   SLIP is available for most Berkeley UNIX-based systems.  It is
   included in the standard 4.3BSD release from Berkeley.  SLIP is
   available for Ultrix, Sun UNIX and most other Berkeley-derived UNIX
   systems.  Some terminal concentrators and IBM PC implementations also
   support it.

   SLIP for Berkeley UNIX is available via anonymous FTP from
   uunet.uu.net in pub/sl.shar.Z.  Be sure to transfer the file in
   binary mode and then run it through the UNIX uncompress program. Take



Romkey