Multicast Routing

Concept: Single Source, Multiple Destinations, Duplication only at branch points.

Present Day Support:

• Communication satellites.
• e-mail lists, internet news distribution. 

Tomorrow's multimedia applications require:

• efficient use of bandwidth. 
• near simultaneous delivery.

Applications: Multicast & Multi-point

One to Many

• Video Distribution
• Wide scale Information dissemination.

Many to Many

• Video Conferencing
• Computer Supported Common Work.
• Distributed interactive simulation.
• Large scale distributed (super)computing.
• Distributed Games

Mobile IP

Routing

based on IP destination address, network prefix (e.g. 129.13.42) determines physical subnet

change of physical subnet implies change of IP address to have a topological correct address (standard IP) or needs special entries in the routing tables

Specific routes to end-systems?

change of all routing table entries to forward packets to the right destination

does not scale with the number of mobile hosts and frequent changes in the location, security problems

Changing the IP-address?

adjust the host IP address depending on the current location

almost impossible to find a mobile system, DNS updates take to long time

TCP connections break, security problems