Mobile IP tutorial
As the internet demand is growing across the world, it has become very important to maintain internet connectivity of the device while moving from place to place. This is achieved using mobile IP concept. Mobile IP can be used for both wired connectivity as well as wireless. In wired connectivity, mobile IP device can be unplugged from one attachment and connected to the other attachment. Mobile IP is more suited to the wireless connection.
In non mobile IP systems, user travelling from one place to the other need to terminate and establish the IP connection each time. Each time connection is established, new temporary IP address is assigned to the user for all the applications. In Mobile IP systems, user is connected with all the applications inspite of movement from one place to the other. The connections is being maintained automatically despite of move.
Figure-1 depicts typical mobile IP scenario for mobile node-A moving from one place to the other. As shown, a mobile node-A is assigned particular network referred as home network. IP address assigned here is referred as home address, which is static. When the host moves to the other network which is referred here as foreign network. One nodeis re-attached it will register with foreign network. It will does this through router referred as foreign agent here. Mobile node communicates care-of address to the home agent, so that it will know the foreign agent's location. This will help in exchange of IP datagrams across the Mobile IP network.
Mobile IP Protocol
To support the communications of IP datagrams mobile IP supports following capabilities.
• Discovery:Mobile node uses discovery procedure to identify prospective home and foreign agents.
• Registration: Mobile node uses registration procedure to communicate home agent about its care-of address while on move.
• Tunneling: It is used to forward IP datagrams from home address to care-of address location.