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The TCP/IP Guide  9  TCP/IP Lower-Layer (Interface, Internet and Transport) Protocols (OSI Layers 2, 3 and 4)       9  TCP/IP Internet Layer (OSI Network Layer) Protocols            9  Internet Protocol (IP/IPv4, IPng/IPv6) and IP-Related Protocols (IP NAT, IPSec, Mobile IP)                 9  Internet Protocol Version 6 (IPv6) / IP Next Generation (IPng)

IPv6 Autoconfiguration and Renumbering 1 IPv6 Datagram Overview and General Structure

Delivery of data over IPv6 internetworks is accomplished by encapsulating higher-layer data into IPv6 datagrams. These serve the same general purpose for IPv6 as IPv4 datagrams do in the older version of the protocol. However, they have been redesigned as part of the overall changes represented by IPv6. IPv6 datagrams have a flexible structure and their format better matches the needs of current IP networks.

In this section I take a look at the format used for IPv6 datagrams. I begin with an overview of the general structure of IPv6 datagrams, describing the major changes and showing how main and extension headers are arranged in the datagram. I then describe the format of the main header, and define and describe the various extension header types. I conclude with a brief explanation of IPv6 options and how they are implemented.

IPv6 Autoconfiguration and Renumbering 1 IPv6 Datagram Overview and General Structure