Quiz 1. AMobile IP give a second IP address to a host who want to be mobile to ensure that even if he change his point of attachment in the internet he will still be identified by her original IP address. Home address IP is used when the device is attached in the home network and care- of address is used when it is away in foreign network. Quiz 1. B Home address- Mobile devices have home address IP; this is IP address which is assigned to device in its home network. Home network- Home network is a network within which device receives it’s identifying home address (IP address). Foreign network- Foreign network is a network within which mobile node operates when it is away from it’s home network. Care- of address- is network –native IP address of a mobile device.
It is the IP address used to identify the device when it is operating in foreign network. It is used to identify the current location of a mobile node. Quiz 1. C A mobile node consists of two addresses. It has a home address which is permanent as well as a care- of address (CoA) which have been associated with network the mobile node intend to visit.
There two kinds of entities that comprise Mobile IP implementation. Information concerning mobiles nodes whose home address is found in the home agent network are stored in a home agent while foreign agent is used to store information of mobile nodes who visit it’s network. At the same time foreign agents advertise care- of addresses aimed to be utilized by Mobile IP. Any node intending to communicate together with the mobile node utilizes the permanent home address of mobile node as a destination address to forward packets to it.
Since home address logically belong to network linked with home agent, the normal IP routing mechanism forward those packets to home agent. Instead of routing those packets toward foreign agent via IP tunnel it encapsulates the datagram giving it a new IP header guided by address of mobile node. As a transmitter mobile node route packets directly to other node via foreign agent, avoiding sending packets via home agent.
it use its permanent home address as source address for the IP packet ( triangular routing ). If needed foreign agent can apply reverse tunneling by tunneling the mobile node packets to home agent which in turn route packet to communicating node. Quiz 1.dTriangular routing, this is a routing where packet are first send to a proxy system way before been transmitted to the targeted destination. It is not convenient to use triangular routing in mobile IP you are most likely to face so many problems, however triangular routing fit well in some networking scenarios.
In mobile IP packets to be sent to mobile node are routed first to home subnet of a mobile node’s, and finally forwarded by home agent to mobile node in it’s current position. But packets sent from mobile node are handled differently, they are sent straight to their destination. These way problems are likely to arise especially in usage of services that require ingress filtering, because source address on the packet is mobile node home address not care- of address which is assigned to node of it’s guest network.
To solve this problem many implementations of Mobile IP provide options of tunneling packets from mobile node via home agent.