RFC 6598 · BEST CURRENT PRACTICE · 2012

IANA-Reserved IPv4 Prefix for Shared Address Space

Overview

RFC 6598, “IANA-Reserved IPv4 Prefix for Shared Address Space”, is a Best Current Practice document published in April 2012 by J. Weil, V. Kuarsingh, C. Donley, C. Liljenstolpe, M. Azinger. It updates RFC 5735. The canonical text is published by the RFC Editor.

Abstract

This document requests the allocation of an IPv4 /10 address block to be used as Shared Address Space to accommodate the needs of Carrier- Grade NAT (CGN) devices. It is anticipated that Service Providers will use this Shared Address Space to number the interfaces that connect CGN devices to Customer Premises Equipment (CPE).

Shared Address Space is distinct from RFC 1918 private address space because it is intended for use on Service Provider networks. However, it may be used in a manner similar to RFC 1918 private address space on routing equipment that is able to do address translation across router interfaces when the addresses are identical on two different interfaces. Details are provided in the text of this document.

This document details the allocation of an additional special-use IPv4 address block and updates RFC 5735. This memo documents an Internet Best Current Practice.

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

What “Best Current Practice” means

Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.

Read this RFC

The canonical text of RFC 6598 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC updates
RFC 5735
Other RFCs from 2012

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