What are the functions of home agent and foreign agent in mobile IP? How does I-TCP differ from traditional TCP? Describe with shome agent & foreign agent and I-TCP vs. traditional TCPuitable diagram.
Home agent is a type of mobility agent. In Mobile Internet Protocol (Mobile IP), a home agent is a router on a mobile node's home network that maintains information about the device's current location, as identified in its care-of address. The home agent uses tunnelling mechanisms to forward Internet traffic so that the device's IP address doesn't have to be changed each time it connects from a different location. A home agent may work in conjunction with a foreign agent, which is a router on the visited network.
A foreign agent which is also a type of mobility agent which works in conjunction with another type of mobility agent known as a home agent to support Internet traffic forwarding for a device connecting to the Internet from any location other than its home network. The home agent tunnels datagrams (packets) intended for the mobile node to a care-of address, and the foreign agent detunnels packets and delivers them to the mobile node.
The Slow start mechanism when the segments are lost of traditional TCP in fixed networks does not work well for wireless networks. To remove this problem indirect TCP(ITCP) was developed.
In I-TCP, the TCP connection between the mobile host (MH) and the correspondent host (CH) is split at the mobility support router (MSR). The connection between the MSR and MH has independent, optimized flow and congestion control from the MSR to CH link.
Briefly describe the congestion control, slow start and fast retransmit mechanism.