RFC 1582 (rfc1582) - Page 2 of 29

Extensions to RIP to Support Demand Circuits

RFC 1582                       Demand RIP                  February 1994


   The WAN circuit manager advises the routing applications on the
   reachability and non-reachability of destinations on the WAN.

Acknowledgements

   I would like to thank colleagues at Spider, in particular Richard
   Edmonstone, Tom Daniel and Alam Turland, Yakov Rekhter (IBM), Martha
   Steenstrup (BBN), and members of the RIP-2 working group of the IETF
   for stimulating discussions and comments which helped to clarify this
   memo.

Conventions

   The following language conventions are used in the items of
   specification in this document:

      o  MUST -- the item is an absolute requirement of the specification.
         MUST is only used where it is actually required for interoperation,
         not to try to impose a particular method on implementors
         where not required for interoperability.

      o  SHOULD -- the item should be followed for all but exceptional cir-
         cumstances.

      o  MAY or optional -- the item is truly optional and may be followed
         or ignored according to the needs of the implementor.

   The words "should" and "may" are also used, in lower case, in their
   more ordinary senses.

Table of Contents

      1. Introduction ...........................................  3
      2. Running a routing Protocol on the WAN ..................  4
          2.1. Overview .........................................  4
          2.2. Presumption of Reachability ......................  6
          2.3. WAN Router list ..................................  7
          2.4. Triggered Updates and Unreliable Delivery ........  8
          2.5. Guaranteeing delivery of Routing Updates .........  8
          2.6. The Routing Database .............................  9
          2.7. New Packet Types ................................. 10
          2.8. Fragmentation .................................... 12
          2.9. Preventing Queue Overload ........................ 13
      3. IP Routing Information Protocol Version 1 .............. 13
      4. IP Routing Information Protocol Version 2 .............. 16
      5. Netware Routing Information Protocol ................... 17
      6. Netware Service Advertising Protocol ................... 20
      7. Timers ................................................. 24



Meyer