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Ad HoC Mobile Wireless netWorks
Tree maintenance phase. Upon link failure, the downstream node
(with a relatively higher msm id) is responsible for rejoining the mul-
ticast tree. Before broadcasting a join-request message, the down-
stream node of a broken link attempts to find potential parent nodes
by locally repairing the route using an expanded-ring search process.
e join-request message is broadcast with a TTL value that restricts
the number of hops the message can propagate. If a node that wants
to rejoin a muticast tree has no valid msm id, it calculates msm id for
itself based on the msm ids of its neighboring node’s msm id and then
joins the multicast tree through the branch reconstruction process
explained before. e beacon upd ...