RFC 8200 - Internet Protocol, Version 6 (IPv6) Specification

Published: July 2017
Status: Standards Track
STD: 86
Authors: S. Deering (Retired), R. Hinden (Check Point Software)
Obsoletes: RFC 2460

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Abstract

This document specifies version 6 of the Internet Protocol (IPv6). It obsoletes RFC 2460.

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Table of Contents

• 1. Introduction
• 2. Terminology
• 3. IPv6 Header Format
• 4. IPv6 Extension Headers
  • 4.1 Extension Header Order
  • 4.2 Options
  • 4.3 Hop-by-Hop Options Header
  • 4.4 Routing Header
  • 4.5 Fragment Header
  • 4.6 Destination Options Header
  • 4.7 No Next Header
  • 4.8 Defining New Extension Headers and Options
• 5. Packet Size Issues
• 6. Flow Labels
• 7. Traffic Classes
• 8. Upper-Layer Protocol Issues
  • 8.1 Upper-Layer Checksums
  • 8.2 Maximum Packet Lifetime
  • 8.3 Maximum Upper-Layer Payload Size
  • 8.4 Responding to Packets Carrying Routing Headers
• 9. IANA Considerations
• 10. Security Considerations
• 11. References
  • 11.1 Normative References
  • 11.2 Informative References

Appendices

• Appendix A. Formatting Guidelines for Options
• Appendix B. Changes Since RFC 2460

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Related Resources

• Official Text: RFC 8200
• Official Page: RFC 8200 DataTracker
• Errata: RFC Editor Errata
• STD 86: This document is part of Internet Standard 86

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Quick Reference

What is IPv6?

IPv6 (Internet Protocol version 6) is the sixth version of the Internet Protocol, designed to succeed IPv4.

Key Improvements

Major changes from IPv4:

• ✅ Expanded Address Space - From 32-bit to 128-bit addresses
• ✅ Simplified Header - More efficient routing processing
• ✅ Improved Extensibility - Flexible extension header mechanism
• ✅ Flow Labels - Better QoS support
• ✅ Autoconfiguration - Simplified network configuration

IPv6 vs IPv4

Feature	IPv4	IPv6
Address Length	32 bits	128 bits
Address Space	~4.3 billion	~340 undecillion
Header Size	20-60 bytes	40 bytes fixed
Fragmentation	Routers can fragment	Source-only fragmentation
Checksum	Header checksum	No header checksum
Configuration	Manual or DHCP	Auto or DHCPv6
Broadcast	Supported	Not supported (multicast)

Use Cases

• 🌐 Internet Backbone - Global IPv6 deployment
• 📱 Mobile Networks - 4G/5G networks
• 🏠 Internet of Things - Massive device connectivity
• 🏢 Enterprise Networks - Future network infrastructure

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