Network Working Group                                        W A Simpson
Internet Draft                                                Daydreamer
expires in six months                                         March 1993



                             PPP over SONET



Status of this Memo

   This memo is the product of the Point-to-Point Protocol Working Group
   of the Internet Engineering Task Force (IETF).  Comments on this memo
   should be submitted to the ietf-ppp@ucdavis.edu mailing list.

   Distribution of this memo is unlimited.

   This document is an Internet Draft.  Internet Drafts are working
   documents of the Internet Engineering Task Force (IETF), its Areas,
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   Please check the 1id-abstracts.txt listing contained in the
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Abstract

   The Point-to-Point Protocol (PPP) [1] provides a standard method of
   encapsulating Network Layer protocol information over point-to-point
   links.

   This document defines a method for using PPP to transport multi-
   protocol datagrams over SONET circuits.












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1.  Introduction

   PPP has three main components:

      1. A method for encapsulating datagrams over serial links.

      2. A Link Control Protocol (LCP) for establishing, configuring,
         and testing the data link connection.

      3. A family of Network Control Protocols (NCPs) for establishing
         and configuring different network layer protocols.

   PPP was designed as a standard method of communicating over point-
   to-point links.  Initial deployment has been over short local lines,
   leased lines, and plain-old-telephone-service (POTS) using modems.
   As new packet services and higher speed lines are introduced, PPP is
   easily deployed in these environments as well.

           One protocol to carry them all.
           One protocol to mind them.
           One protocol to link them all,
           and in the network bind them.


   This specification is primarily concerned with the use of standard
   PPP frames over SONET links.  Since SONET is a point-to-point
   circuit, PPP is well suited to use over SONET.

2.  Encapsulation

   PPP provides an encapsulation protocol over both bit-oriented
   synchronous links and asynchronous links with 8 bits of data and no
   parity.  These links MUST be full-duplex, but MAY be either dedicated
   or circuit-switched.  This fits the SONET model, which looks like an
   asynchronous link to the link-layer encapsulation.

   PPP uses HDLC [2] as a basis for the encapsulation.  It is completely
   suitable for use with the SONET link.  It is distinguishable from
   other uses of the SONET link, such as Asynchronous Transfer Mode
   (ATM).


3.  Configuration Details

   The standard LCP configuration defaults apply to SONET links.

   The following Configurations Options are recommended:




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      Magic Number
      Link Quality Monitoring
      No Address and Control Field Compression
      No Protocol Field Compression


   Since the SONET link is treated as an asynchronous link, the Flag and
   Escape values MUST be escaped.  However, the default ACCM for SONET
   is 0 (no control octets escaped).









































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Security Considerations

   Security issues are not discussed in this memo.

References

   [1]   Simpson, W. A., "The Point-to-Point Protocol", RFC 1331, May
         1992.

   [2]   International Organization For Standardization, ISO Standard
         3309-1979, "Data communication - High-level data link control
         procedures - Frame structure", 1979.

Acknowledgments


Chair's Address

   The working group can be contacted via the current chair:

      Brian Lloyd
      B.P. Lloyd & Associates
      3420 Sudbury Road
      Cameron Park, California 95682

      Phone: (916) 676-1147

      EMail: brian@lloyd.com


Author's Address

   Questions about this memo can also be directed to:

      William Allen Simpson
      Daydreamer
      Computer Systems Consulting Services
      P O Box 6205
      East Lansing, MI  48826-6205

      EMail: Bill.Simpson@um.cc.umich.edu










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                           Table of Contents


     1.     Introduction ..........................................    1

     2.     Encapsulation .........................................    1

     3.     Configuration Details .................................    1

     SECURITY CONSIDERATIONS ......................................    3

     REFERENCES ...................................................    3

     ACKNOWLEDGEMENTS .............................................    3

     CHAIR'S ADDRESS ..............................................    3

     AUTHOR'S ADDRESS .............................................    3




































Bill.Simpson@um.cc.umich.edu