referred to are listed above.
o Connectivity to an attached network changes.
a. Update the Minimum Distance Vector.
b. Recompute the Routing Updates.
c. Recompute the Routing Table.
d. If any routing update has changed, send the new routing
updates to the neighbors.
o Connectivity to a neighbor gateway changes.
a. Update the Neighbor Connectivity Vector.
b. Recompute the Minimum Distance Vector.
c. Recompute the Routing Updates.
d. Recompute the Routing Table.
e. If any routing update has changed, send the new routing
updates to the neighbors.
o A Routing Update message is received.
a. Compare the Internet source address of the Routing Update
message to the Neighbor Addresses. If the address is not
on the list, add it to the list of Neighbor Addresses,
increment the Number of Neighbors, and set the Receive
Sequence Number for this neighbor to the sequence number
in the Routing Update message.
b. Compare the Receive Sequence Number for this neighbor to
the sequence number in the Routing Update message to
determine whether or not to accept this message. If the
message is rejected, send a Negative Acknowledgment
message. If the message is accepted, send an
Acknowledgment message and proceed with the following
steps.
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RFC823
c. Compare the networks reported in the Routing Update
message to the Number of Networks. If new networks are
reported, enter them in the network vectors, increase the
number of networks, and expand the Distance Matrix to
account for the new networks.
d. Copy the routing update received into the appropriate row
of the Distance Matrix.
e. Recompute the Minimum Distance Vector.
f. Recompute the Routing Updates.
g. Recompute the Routing Table.
h. If any routing update has changed, send the new routing
updates to the neighbors.
o An Acknowledgment message is received.
Compare the sequence number in the message to the Send
Sequence Number. If the Send Sequence Number is
acknowledged, update the entry in the Received
Acknowledgment Vector for the neighbor that sent the
acknowledgment.
o A Negative Acknowledgment message is received.
Compare the sequence number in the message to the Send
Sequence Number. If necessary, replace the Send Sequence
Number, and retransmit the routing updates.
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RFC823
REFERENCES
[1] Postel, J. (ed.), "Internet Protocol - DARPA Internet
Program Protocol Specification," RFC791, USC/Information
Sciences Institute, September 1981.
[2] Strazisar, V., "Gateway Routing: An Implementation
Specification," IEN-30, Bolt Beranek and Newman Inc., August
1979.
[3] Strazisar, V., "How to Build a Gateway," IEN-109, Bolt
Beranek and Newman Inc., August 1979.
[4] Postel, J., "Internet Control Message Protocol - DARPA
Internet Program Protocol Specification," RFC792,
USC/Information Sciences Institute, September 1981.
[5] Postel, J., "Assigned Numbers," RFC790, USC/Information
Sciences Institute, September 1981.
[6] Littauer, B., Huang, A., Hinden, R., "A Host Monitoring
Protocol," IEN-197, Bolt Beranek and Newman Inc., September
1981.
[7] Santos, P., Chalstrom, H., Linn, J., Herman, J.,
"Architecture of a Network Monitoring, Control and
Management System," Proc. of the 5th Int. Conference on
Computer Communication, October 1980.
[8] Haverty, J., "XNET Formats for Internet Protocol Version 4,"
IEN-158, Bolt Beranek and Newman Inc., October 1980.
[9] Mathis, J., Klemba, K., Poggio, "TIU Notebook- Volume 2,
Software Documentation," SRI, May 1979.
[10] Rosen, E., "Exterior Gateway Protocol," IEN-209, Bolt
Beranek and Newman Inc., August 1982.