5.3 Header Extension

[RFC3775] defines new extension headers and several new types and options for existing headers for Mobile IPv6. The specification also defines some header formats of Neighbor Discovery [RFC2461] which are modified for Mobile IPv6. The following is a list of new or modified headers and options. The detailed description of each header and option will be discussed in Sections 5.3.2 to 5.3.7.

Home Address option The Home Address option is a newly defined destination option which carries the home address of a mobile node when packets are sent from a mobile node.

Type 2 Routing Header The Type 2 Routing Header is a newly defined routing header type which carries a home address of a mobile node when packets are sent from a home agent or a correspondent node to a mobile node.

Mobility Header The Mobility Header is a newly defined Extension Header which carries the signaling information of the Mobile IPv6 protocol.

Figure 5-4: The return routability procedure

Router Advertisement message The Router Advertisement message is modified to include a flag which indicates whether a router has the home agent function or not.

Prefix Information option The Prefix Information option is one of the Neighbor Discovery options used to distribute prefix information of a network from a router to other nodes connected to the network. In Mobile IPv6, a home agent includes its address in this option as a part of the prefix information. All home agents on the same...