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=== Routing Algorithm ===

The Distance Vector algorithm is one in which global information is given to local nodes - that is neighboring nodes. Below is a table of how a node interacts with it's peers, but first an example:

{{{
  B
 / \
A - C
|\   \
| E   D
|    /
F---G

Figure 1
}}}

We build two tables 

   1. '''Initial''' distances stored at each node (global view)
   2. '''Initial''' routing table at node A.

||Information Stored ||||||||||||||Distance to reach Node||
||at Node A||A||B||C||D||E||F||G||
||A||0||1||1||inf||1||1||inf||
||B||1||0||1||inf||inf||inf||inf||
||C||1||1||0||1||inf||inf||inf||
||D||inf||inf||1||0||inf||inf||1||
||E||1||inf||inf||inf||0||inf||inf||
||F||1||inf||inf||inf||inf||0||1||
||G||inf||inf||inf||1||inf||1||0||

.

||Destination||Cost||Next Hop||
||B||1||B||
||C||1||C||
||D||inf||-||
||E||1||E||
||F||1||F||
||G||inf||-||

=== Notes ===

||Who: || Broadcasts information to it's neighbors ||
||What: || (Destination, Cost) tuples ||
||When: || Periodically and when triggered by a change. Information is deleted after a time out. ||

   * Converges when the topology is static
   * Suseptible to routing loops - race to infinity problem.
   * Routing loops '''between neighbors''' can be fixed with either SplitHorizon or SplitHorizon with poison reverse.

Example: InteriorGatewayRoutingProtocol (IGRP) RoutingInformationProtocol (RIP) as in Rest In Peace.

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