RFC 2101 (rfc2101) - Page 1 of 13
IPv4 Address Behaviour Today
Alternative Format: Original Text Document
Network Working Group B. Carpenter
Request for Comments: 2101 J. Crowcroft
Category: Informational Y. Rekhter
IAB
February 1997
IPv4 Address Behaviour Today
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 main purpose of this note is to clarify the current
interpretation of the 32-bit IP version 4 address space, whose
significance has changed substantially since it was originally
defined. A short section on IPv6 addresses mentions the main points
of similarity with, and difference from, IPv4.
Table of Contents
1. Introduction.................................................1
2. Terminology..................................................2
3. Ideal properties.............................................3
4. Overview of the current situation of IPv4 addresses..........4
4.1. Addresses are no longer globally unique locators.........4
4.2. Addresses are no longer all temporally unique............6
4.3. Multicast and Anycast....................................7
4.4. Summary..................................................8
5. IPv6 Considerations..........................................8
ANNEX: Current Practices for IPv4 Address Allocation & Routing..9
Security Considerations........................................10
Acknowledgements...............................................11
References.....................................................11
Authors' Addresses.............................................13
1. Introduction
The main purpose of this note is to clarify the current
interpretation of the 32-bit IP version 4 address space, whose
significance has changed substantially since it was originally
defined in 1981 [RFC 791].
Carpenter, et. al. Informational