Gugrajah_Yuvaan_ Ramesh_2003.pdf

Routing Protocols for Ad Hoc Networks Chapter 2
The spine IS obtained by using an approximation to the minimum connected
dominating set (MCnS) [Siva97] of the ad hoc network topology. The MCnS of an
ad hoc network is depicted in Figure 2-6. A dominating set in a network is the subset
of nodes such that every node in the network is either in the dominating set or is a
neighbour of one of the nodes in the dominating set. A connected dominating set is a
dominating set consisting of nodes which are able to communicate with each other
without needing to use nodes that are not elements of the dominating set.
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Figure 2-6. Depiction of the MCDS and spine in spine routing
The MCnS approximation consists of an initialisation phase where nodes flood
messages to their neighbours informing their neighbours of the number of neighbours
that they have. It is assumed that nodes initially are aware of their own neighbours.
The nodes are then able to determine who has the most neighbours and which node
should form part of the dominating set by "marking" nodes with the most
neighbours. For example, if two neighbouring nodes A and B find that node A has
more neighbours than B then A also becomes the dominating node of node B. The
procedure is repeated until all nodes are either in the dominating set or are at least
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