Chapter 10. IPv6

IPv6 Packet Headers and Addressing

Configuring IPv6

IPv4-to-IPv6 Transition Mechanisms

Internet Protocol Version 6 (IPv6) is the new version of the Internet Protocol (IP). The Internet Protocol allows numerous nodes on different networks to interoperate seamlessly. Internet Protocol Version 4 (IPv4) is currently used in intranets and private networks, as well as the Internet. IPv6 is the successor to IPv4 and is based for the most part on IPv4. IPv6 builds on the functionality of IPv4, providing improvements to addressing, configuration and maintenance, and security. IPv6 offers the following benefits:

• Expanded addressing capabilities ”IPv6 provides a larger address space. IPv4 addresses consist of 32 bits, while IPv6 addresses consist of 128 bits, thus increasing the address space by approximately 10 ²⁹ unique addresses.

• Header format simplification ”IPv6 packet header format designed to be efficient. IPv6 standardizes the size of the packet header to 40 bytes, divided into 8 fields.

• Improved support for extensions and options ”Extension headers carry Internet-layer information and have a standard size and structure.

• Flow labeling capability ”Flow labels provide consistent handling of packets belonging to the same flow.

• Improved privacy and security ”IPv6 supports extensions for authentication and data integrity, which enhances privacy and security.

Table 10.1 lists the IPv6 standards and protocol extensions supported by the JUNOS software.

Table 10.1. IPv6 Standards Supported by JUNOS Software

Standard	Title
RFC 2460	Internet Protocol, Version 6 (IPv6)
RFC 2464	Transmission of IPv6 Packets over Ethernet Networks
RFC 2373	IP Version 6 Addressing Architecture
RFC 2472	IP Version 6 over PPP
RFC 2461	Neighbor Discovery for IP Version 6 (IPv6)
RFC 1157	A Simple Network Management Protocol (SNMP)
RFC 1213	Management Information Base for Network Management of TCP/IP-Based Internets: MIB-II
RFC 1215	A Convention for Defining Traps for Use with SNMP
RFC 1195	Use of OSI IS-IS for Routing in TCP/IP and Dual Environments
RFC 1771	A Border Gateway Protocol 4 (BGP-4)
RFC 1772	Application of the Border Gateway Protocol in the Internet
RFC 1901	Introduction to Community-based SNMPv2
RFC 1902	Structure of Management Information for Version 2 of the Simple Network Management Protocol (SNMPv2)
RFC 1905	Protocol Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)
RFC 1965	Autonomous System Confederations for BGP
RFC 1966	BGP Route Reflection: An Alternative to Full-Mesh IBGP
RFC 1997	BGP Communities Attribute
RFC 2080	RIPng for IPv6
RFC 2081	RIPng Protocol Applicability Statement
RFC 2270	Using a Dedicated AS for Sites Homed to a Single Provider
RFC 2283	Multiprotocol Extensions for BGP-4
RFC 2385	Protection of BGP Sessions via the TCP MD5 Signature Option
RFC 2439	BGP Route Flap Damping
RFC 2545	Use of BGP-4 Multiprotocol Extensions for IPv6 Interdomain Routing
RFC 2578	Structure of Management Information Version 2 (SMIv2)
RFC 2763	Dynamic Hostname Exchange Mechanism for IS-IS
RFC 2893	Transition Mechanisms for IPv6 Hosts and Routers
Internet Draft draft-ietf-isis-ipv6-02.txt	Routing IPv6 with IS-IS
Internet Draft draft-ietf-idr-cap-neg-01.txt	Capabilities Negotiation with BGP4
Internet Draft draft-ramachandra-bgp-ext-communities-09.txt	BGP Extended Communities Attribute
ISO/IEC 10589	Information technology, Telecommunications and information exchange between systems, Intermediate system to intermediate system intradomain routing information exchange protocol for use in conjunction with the protocol for providing the connectionless-mode network service (ISO 8473)