Gugrajah_Yuvaan_ Ramesh_2003.pdf

Simulation ofa Load Balancing Routing Protocol Chapter 3
intennediate nodes to respond to route requests prevents the further propagation of
the route request, congestion can result in the network.
0
0 0
0
0
0 0 node
0 • congested node
route
Figure 3-2. Network congestion due to intermediate routes replying to
route requests
3.2.2. Original DLAR Schemes
The authors [GerlaOO] of DLAR originally suggested 3 schemes that could be used.
The three schemes vary in the manner in which the buffers at each intennediate node
are evaluated. The three DLAR schemes operate as follows:
a) DLAR scheme 1: The first scheme adds the routing load of each intennediate
node on the route and selects the route with the least sum of data packets in
the buffers. Iftwo or more routes have the same sum of data packets, then the
shorter route is selected. If the shortest routes are the same length then the
route whose route request arrived first is the route that is selected as the most
appropriate.
b) DLAR scheme 2: The second scheme uses the average number of packets
buffered at each intermediate node. The route with the lowest average
number of buffered packets is selected as the best route to use. The tiebreaker
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