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CS4461: Difference between revisions
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-src or dst informs network layer of its desire to terminate the VC.
-The network layer then updates forwarding tables to delete the routes.
Datagram Networks:
Each time an end system wants to send a packet it stamps the dst address on the packet and sends it to the network. The packet is sent through a series of routers. Each router uses the dst address to forward the packet.
-lookup the appropriate output link interface in the table
-forward the packet out the chosen interface
Matches the prefix of the dst address and chooses output link based on that.
Longest Prefix Matching Rule
-find the longest matching entry in the table
-forward the packet to the link interface associated with that prefix
Problem - contiguous blocks of address space are getting smaller meaning forwarding tables get larger.
No connection state information is maintained, but forwarding state information is. This happens on a specified interval of time rather than each time a connection is started and ended.
Problem - Forwarding tables can be modified before all the info is transmitted so the paths of individual packets may differ and packets may arrive out of order.
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