Summary: | 碩士 === 國立中正大學 === 資訊管理所 === 94 === Broadcasting is an important communication way in ad–hoc wireless network to provide communication among nodes. The broadcasting may use Blind flooding method, which is commonly used in most of the routing algorithms. This method ensures the coverage for broadcasting, but it takes a lot of overhead for many redundant retransmissions, causing the broadcast storm problem since of the heavy contentions and packets collisions.
To resolve this broadcast storm problem, many broadcasting algorithm is proposed. The object of these broadcast schemes is to find a set of forward nodes; called MCDS (Minimum connected dominating set). But the problem to find MCDS has been proved to be an NP-complete problem. An approximate MCDS is to chase instead. On other hand ad hoc wireless networks have many unstable factors causing the transmission being unreliable. Thus, the broadcasting algorithm needs fault tolerant capability to solve the possible failure of broadcasting process. We propose self-pruning-with-fault-tolerant (SPFT) algorithm to achieve fault tolerance and reachable capability. Based on the self–pruning method, SPFT algorithm can reduce the redundant transmissions. In addition, in order to increase the fault tolerance degree, SPFT algorithm selects the stable links in transmission to ensure the better success ratio of transmission as well as uses the comparison mechanism to deal with the failure transmissions. With the above strategies and perform extensive simulation. The experiment results show that our algorithm has the fault-tolerant capability and achieves the efficiency and reliability for broadcasting in ad hoc wireless network.
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