CN SEMINAR

 What is Mobile IP?

         ■Mobile IP is able to track a mobile host without needing to change the mobile host's long-term IP address.

        ■Its goal is to provide the ability of an host to stay connected to the internet regardless of their location.

        ■Mobile IP is an internet protocol designed to support host mobility.

Mobile IP Features :

Transparency :

          ■ Mobile end-systems keep their IP address.

          ■ Continuation of communication after interruption of link possible. 

          ■Point of connection to the fixed network can be changed.

Compatibility :

        ■No changes to current end-systems and routers required.

       ■ Mobile end-systems can communicate with fixed systems.

Security :

        ■ Authentication of all registration messages.

        ■Efficiency and scalability only little additional messages to the mobile system required (connection typically via a low bandwidth radio link).

        ■ World-wide support of a large number of mobile systems in the whole Internet.

Terminology :

 Mobile Node (MN):

        ■ A host or router that may change its point of attachment from one network or sub network to another through the internet.

        ■This entity is reassigned a fixed home address on a home network, which other correspondent hosts will use to address their packets to regardless of its current location..

Home Agent (HA):

        ■ A router that maintain a list of registered mobile nodes in a visitor list.

        ■It is used to forward mobile node-address packets to the appropriate local network when the mobile nodes are away from home.

        ■After checking with the current mobility bindings for a particular mobile node.

        ■It encapsulated datagram and sends it to the mobile host's current temporary address when the mobile node.

Foreign Agent (FA):

      ■ A router that assists a locally reachable mobile node that is away from its home network. 

      ■It delivers information between the mobile node and the home agent.

 Correspondent Node (CN):

       ■This node sends the packets which are addressed to the communication partner.

Care-of-address (COA):

        ■An address which identifies the mobile node's current location. It can be viewed as the end of a tunnel directed towards a mobile node.

        ■It can be either assigned dynamically or associated with its foreign agent.

Working of Mobile IP:

  Mobile IP has three main phases are namely 

Mobile IP :

          •Agent discovery

          • Registration

          •Tunneling

Agent Discovery :

   ■ The Mobile Node discovers it's foreign agent and home agent during it's agent discovery.

Registration:

          ■ The Mobile Node registers it's current Location with foreign agent and home agent during registration.

Tunneling:

          ■Tunneling is help us to waiting the packets to the mobile node.

          ■Care of Address (COA) is current location of mobile node on the foreign network.

          ■Tunneling passes the datagram from home agent address to the foreign agent and it reaches care of address. 

          ■The home agent address and care of address are two address for the mobile node.

          ■Here the home agent address it a static one and its a fixed IP address.

          ■And the CoA (Care of address) is a dynamic, it changes from one location to another location.

          ■ to the main address that it requires home mobile node is the home agent IP address.

          ■ to the CoA is the termination point of tunnel. towards it's mobile node when it's in the foreign network.

 Key Mechanism in Mobile IP:

              1) Discovering the COA

              2) Registering the COA

              3) Tunneling the COA.

Internet Protocol version 6 (IPv6) :

            ■IPv6 was developed by Internet Engineering Task Force (IETF) to deal with the problem of IP v4 exhaustion. 

            ■IPv6 is a 128-bits address having an address space of 2^128, which is way bigger than IPv4. 

            ■In IPv6 we use Colon-Hexa representation.

            ■ There are 8 groups and each group represents 2 Bytes. 

In IPv6 representation, we have three addressing methods : 

                      ■  Unicast

                      ■  Multicast

                      ■  Anycast

1. Unicast Address –

                     ■ Unicast Address identifies a single network interface. 

                     ■ A packet sent to a unicast address is delivered to the interface identified by that address. 

2. Multicast Address –

                      ■Multicast Address is used by multiple hosts, called as Group, acquires a multicast destination address.

                      ■These hosts need not be geographically together. 

                      ■If any packet is sent to this multicast address, it will be distributed to all interfaces corresponding to that multicast address. 

3. Anycast Address –

                     ■Address is assigned to a group of interfaces. 

                     ■Any packet sent to an anycast address will be delivered to only one member interface (mostly nearest host possible). 

Note: 

                ■Broadcast is not defined in IPv6.