RFC 1620 (rfc1620) - Page 1 of 19
Internet Architecture Extensions for Shared Media
Alternative Format: Original Text Document
Network Working Group B. Braden
Request for Comments: 1620 ISI
Category: Informational J. Postel
ISI
Y. Rekhter
IBM Research
May 1994
Internet Architecture Extensions for Shared Media
Status of This Memo
This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
Abstract
The original Internet architecture assumed that each network is
labeled with a single IP network number. This assumption may be
violated for shared media, including "large public data networks"
(LPDNs). The architecture still works if this assumption is
violated, but it does not have a means to prevent multiple host-
router and router-router hops through the shared medium. This memo
discusses alternative approaches to extending the Internet
architecture to eliminate some or all unnecessary hops.
Table of Contents
1. INTRODUCTION .................................................. 2
2. THE ORIGINAL INTERNET ARCHITECTURE ............................ 2
3. THE PROBLEMS INTRODUCED BY SHARED MEDIA ....................... 4
4. SOME SOLUTIONS TO THE SM PROBLEMS ............................. 7
4.1 Hop-by-Hop Redirection ................................... 7
4.2 Extended Routing ......................................... 11
4.3 Extended Proxy ARP ....................................... 13
4.4 Routing Query Messages ................................... 14
4.5 Stale Routing Information ................................ 14
4.6 Implications of Filtering (Firewalls) .................... 15
5. SECURITY CONSIDERATIONS ....................................... 16
6. CONCLUSIONS ................................................... 17
7. ACKNOWLEDGMENTS ............................................... 17
8. REFERENCES .................................................... 18
Authors' Addresses ............................................... 19
Braden, Postel & Rekhter