RFC 4193 - Unique Local IPv6 Unicast Addresses

• Status: Proposed Standard
• Published: October 2005
• Stream: IETF
• Errata: No Errata

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Abstract

This document defines an IPv6 unicast address format that is globally unique and is intended for local communications, usually inside of a site. These addresses are not expected to be routable on the global Internet.

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Status of This Memo

This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

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Copyright Notice

Copyright (C) The Internet Society (2005).

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Contents

• 1. Introduction
• 2. Acknowledgements
• 3. Local IPv6 Unicast Addresses
  • 3.1. Format
    • 3.1.1. Background
  • 3.2. Global ID
    • 3.2.1. Locally Assigned Global IDs
    • 3.2.2. Sample Code for Pseudo-Random Global ID Algorithm
    • 3.2.3. Analysis of the Uniqueness of Global IDs
  • 3.3. Scope Definition
• 4. Operational Guidelines
  • 4.1. Routing
  • 4.2. Renumbering and Site Merging
  • 4.3. Site Border Router and Firewall Packet Filtering
  • 4.4. DNS Issues
  • 4.5. Application and Higher Level Protocol Issues
  • 4.6. Use of Local IPv6 Addresses for Local Communication
  • 4.7. Use of Local IPv6 Addresses with VPNs
• 5. Global Routing Considerations
  • 5.1. From the Standpoint of the Internet
  • 5.2. From the Standpoint of a Site
• 6. Advantages and Disadvantages
  • 6.1. Advantages
  • 6.2. Disadvantages
• 7. Security Considerations
• 8. IANA Considerations
• 9. References
  • 9.1. Normative References
  • 9.2. Informative References
• Authors' Addresses
• Appendix A. Full Copyright Statement and Intellectual Property

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Related Resources

• Official Text: https://www.rfc-editor.org/rfc/rfc4193.txt
• Official Page: https://datatracker.ietf.org/doc/html/rfc4193
• Info: https://www.rfc-editor.org/info/rfc4193