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UpdatedBEST CURRENT PRACTICEIETF streamBCP5

RFC 1918: Address Allocation for Private Internets

Still current, but amended. Parts of this document are changed or extended by RFC 6761. Read both.

In plain English — editorial summary, not part of the RFC

RFC 1918 reserves three blocks of IPv4 addresses for use inside private networks. Anyone can use these addresses on their own network, and no router on the public internet will forward them, so they can be reused endlessly without collisions. This is why your home or office network almost certainly hands out a 192.168.x.x or 10.x.x.x address.

  • ·10.0.0.0 – 10.255.255.255 (10.0.0.0/8) — 16,777,216 addresses
  • ·172.16.0.0 – 172.31.255.255 (172.16.0.0/12) — 1,048,576 addresses
  • ·192.168.0.0 – 192.168.255.255 (192.168.0.0/16) — 65,536 addresses
  • ·Traffic to these ranges must not be routed across the public internet; a NAT device translates them to a public address on the way out.
Original abstract from the RFC

This document describes address allocation for private internets. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.

Document record

Document ID
RFC1918
Published
February 1996
Authors
Y. Rekhter; B. Moskowitz; D. Karrenberg; G. J. de Groot; E. Lear
Status
BEST CURRENT PRACTICE
Stream
IETF
Area
ops-old
Pages
9
Also known as
BCP5
Obsoletes:
RFC 1597, RFC 1627
Updated by:
RFC 6761

Topics

Standards lineage

This document is one revision in a chain of 3 RFCs, each formally replacing the one before it.

  1. RFC 1597 (1994)
  2. RFC 1627 (1994)
  3. RFC 1918 (1996)

Read the full history of Address Allocation for Private Internets →

Referenced by

One later RFC formally updates or obsoletes part of this document.

Related documents

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About this page

The document record above — title, authors, date, status, stream, area, relationships, DOI and errata — is imported verbatim from the public RFC Editor index. The “in plain English” section is editorial: written by The metasystema editorial team, not part of the RFC. Where the two differ, the RFC text governs.

Last checked against the RFC Editor index on . RFCs are never revised after publication; changes are issued as new documents.

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canonical URL: /rfc/1918-address-allocation-for-private-internets