What is Mobile IP? Explain the various Components of Mobile IP.

M.C.A. (Management faculty) - (2012 Pattern) (Semester-IV)
IT 42 : MOBILE COMPUTING
Time : 3 Hours Max. Marks 70
1. Instructions to the candidates:
2. Question no 1 is compulsory
3. Answer any five questions from remaining.
4. Neat diagrams must be drawn wherever necessary.

Q.1) a) What is Mobile IP? Explain the various Components of Mobile IP.

Ans.
Mobile IP (or MIP) is a communications protocol that allows users to move from one network to another network with same IP address. It ensures that communication will continue without user’s sessions or connections being dropped. When a user leaves the home network and enters in another network (foreign network), the foreign network uses the mobile IP protocol to inform the home network of a care-of address to which all packets for the user's device should be sent.

Home Address is the permanent IP address assigned to the mobile node. Mobile node uses this address in its home address.

Care-Of Address is the temporary address used by a mobile node while it is moving away from its home network.

Mobile IP has the following three components.

- Mobile Node
- Home Agent
- Foreign Agent

Mobile Node: Any device those have roaming facility such as a cell phone, personal digital assistant, or laptop.

Home Agent: It is a router on the home network and working as communication point with the Mobile Node. It stores information about mobile nodes whose permanent home address is in the home agent’s network. It tunnels data from a called a Correspondent Node, to the roaming Mobile Node.

Foreign Agent: It available in another network and stores information about mobile nodes visiting its network. The Foreign Agent is a router that advertises care-of addresses, which are used by mobile IP. It also delivers packets from the Home Agent to the Mobile Node while roaming in another network.