RFC 3021 · PROPOSED STANDARD · 2000

Using 31-Bit Prefixes on IPv4 Point-to-Point Links

Overview

RFC 3021, “Using 31-Bit Prefixes on IPv4 Point-to-Point Links”, is a Proposed Standard document published in December 2000 by A. Retana, R. White, V. Fuller, D. McPherson. The canonical text is published by the RFC Editor.

Abstract

With ever-increasing pressure to conserve IP address space on the Internet, it makes sense to consider where relatively minor changes can be made to fielded practice to improve numbering efficiency. One such change, proposed by this document, is to halve the amount of address space assigned to point-to-point links (common throughout the Internet infrastructure) by allowing the use of 31-bit subnet masks in a very limited way. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 3021 is hosted at rfc-editor.org. Available in TXT,HTML.

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