IPv6 Mobility Mobility is a very important feature in networks today. Mobile IP is an IETF standard available for both IPv4 and IPv6. Mobile IP enables mobile devices to move without breaking current connections. In IPv6, mobility is built in, which means that any IPv6 node can use it as needed. However, in IPv4, mobility is a new function that must be added. The routing headers of IPv6 make Mobile IPv6 much more efficient for end nodes than Mobile IPv4. Mobility takes advantage of the flexibility of IPv6. For example, binding uses some header options (destination) that are mandatory for every IPv6 device. Also, IPv6 mobility creates a new “mobility” extension header.
IPv6 mobility is different from IPv4 mobility in several ways:

The IPv6 address space enables Mobile IP deployment in any kind of large environment.
Because of the vast IPv6 address space, foreign agents are no longer required. Infrastructures do not need an upgrade to accept Mobile IPv6 nodes, so the care-of address (CoA) can be a global IPv6 routable address for all mobile nodes.
The Mobile IPv6 model takes advantage of some of the benefits of the IPv6 protocol itself. Examples include option headers, neighbor discovery, and autoconfiguration.
In many cases, triangle routing is eliminated, because Mobile IPv6 route optimization allows mobile nodes and corresponding nodes to communicate directly. Support for route optimization is a fundamental part of the protocol, rather than a nonstandard set of extensions. Support is also integrated into Mobile IPv6 for allowing route optimization to coexist efficiently with routers that perform ingress filtering. Mobile IPv6 route optimization can operate securely even without prearranged security associations. It is expected that route optimization can be deployed on a global scale between all mobile nodes and correspondent nodes.
Mobile nodes work transparently even with other nodes that do not support mobility (same as in IPv4 mobility).
The dynamic home agent address-discovery mechanism in Mobile IPv6 returns a single reply to the mobile node. The directed broadcast approach used in IPv4 returns separate replies from each home agent.
Most packets sent to a mobile node while it is away from home in Mobile IPv6 are sent using an IPv6 routing header rather than IP encapsulation, reducing the amount of resulting overhead compared to Mobile IPv4.

Content 8.4 IPv6 Routing 8.4.1 Describing IPv6 Routing Similar to IP version 4 (IPv4) classless interdomain routing (CIDR), IPv6 uses longest-prefix match routing. Recent protocol versions handle longer IPv6 addresses and different header structures. Currently, the updated routing protocols shown in Figure are available. The following are summaries of various routing protocols used with IPv6. Static Routing
Static routing with IPv6 is used and configured in the same way as IPv4. There is an IPv6-specific requirement per RFC 2461: A router must be able to determine the link-local address of each of its neighboring routers to ensure that the target address of a redirect message identifies the neighbor router by its link-local address. This requirement basically means that using a global unicast address as a next-hop address with routing is not recommended. RIPng
Routing Information Protocol next generation (RIPng, RFC 2080) is a distance vector routing protocol with a limit of 15 hops that uses split horizon and poison reverse to prevent routing loops. The protocol implementation for IPv6 includes these characteristics:

Based on IPv4 RIP version 2 (RIPv2) and similar to RIPv2
Uses IPv6 for transport
IPv6 prefix, next-hop IPv6 address
Uses the multicast group FF02::9, the all-RIP-routers multicast group, as the destination address for RIP updates
Updates sent on UDP port 521

OSPFv3
The protocol implementation for IPv6 includes these characteristics:

Based on OSPF version 2 (OSPFv2), with enhancements
Distributes IPv6 prefixes
Runs directly over IPv6
Operates as “ships in the night” with OSPFv2

This implementation adds these IPv6-specific attributes:

128-bit addresses
Link-local address
Multiple addresses and instances per interface
Authentication (now uses IPsec)
OSPFv3 runs over a link rather than a subnet

IS-IS
Large address support facilitates the IPv6 address family. Intermediate System to Intermediate System (IS-IS) is the same as IPv4 with the following extensions added:

Two new Type, Length, Value (TLV) attributes
IPv6 reachability
IPv6 interface address
New protocol IDS

EIGRP
Enhanced Interior Gateway Routing Protocol (EIGRP) can be used to route IPv6 prefixes. EIGRP IPv4 runs over an IPv4 transport, communicates only with IPv4 peers, and advertises only IPv4 routes. EIGRP for IPv6 follows the same model. EIGRP for IPv4 and EIGRP for IPv6 are configured and managed separately. However, the configuration of EIGRP for IPv4 and IPv6 is similar and provides operational familiarity and continuity. Multiprotocol BGP (MP-BGP)
To make Border Gateway Protocol version 4 (BGP4) available for other network-layer protocols, RFC 2858 (which replaces the obsolete RFC 2283) defines multiprotocol extensions for BGP4. Multiprotocol BGP is used to enable BGP4 to carry the information of other protocols, for example, Multiprotocol Label Switching (MPLS) and IPv6. Web Links Implementing Static Routes for IPv6
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Content 8.4 IPv6 Routing 8.4.2 OSPFv3 and IPv6 OSPF is a link-state IP routing protocol. Think of a link as being an interface on a networking device. A link-state protocol makes its routing decisions based on the states of the links that connect source and destination machines. The state of a link is a description of that interface and its relationship to its neighboring networking devices. The interface information includes the IPv6 prefix of the interface, the network mask, the type of network that it is connected to, the routers connected to that network, and so on. This information is propagated in various types of link-state advertisements (LSAs). A collection of LSA data on a router is stored in a link-state database (LSDB). The contents of the database, when subjected to Dijkstra’s algorithm, result in the creation of the OSPF routing table. The difference between the database and the routing table is that the database contains a complete collection of raw data. The routing table contains a list of shortest paths to known destinations via specific router interface ports. OSPFv3, which is described in RFC 2740, supports IPv6. Web Links Implementing OSPF for IPv6
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Content 8.4 IPv6 Routing 8.4.3 Similarities Between OSPFv2 and OSPFv3 Many of the OSPF for IPv6 features are the same as in OSPFv2. OSPFv3 for IPv6, which is described in RFC 2740, expands on OSPFv2 to provide support for IPv6 routing prefixes and the larger size of IPv6 addresses. Other