廣播為一被廣泛使用在隨意無線網路環境中的通訊技術，其可被運用於路徑找尋、找尋某一特定節點或是發送緊急信號給網路上所有節點。然而，傳統的廣播技術“洪流”容易造成傳遞過多多餘封包、網路擁塞和傳送封包碰撞，我們稱之為“廣播風暴問題”。MPR(Multipoint Relay Broadcasting)，為一能有效處理此問題的廣播方法。但MPR並無考慮到網路節點的移動性及節省有限電能使用的重要性。所以MPR中的每一個節點在做傳輸時，都是用預設的最大傳輸範圍來概括所有鄰居節點。許多不必要的電能消耗將造成龐大負擔。在MPR中，邊界節點是最容易被挑選為繼續傳遞廣播封包的節點(forwarding node)，但邊界節點又是最容易因移動而失去聯絡的節點。且在目前所被提出的廣播方法中，大多都是以挑選具有高效益的邊界點為主。因此，在本論文中，我們提出一個新的廣播技術，稱為DP-MPR(Dynamical Power-aware Multipoint Relay)。DP-MPR定義了兩個MNB (Moving out the Negligible Border node)條件，動態地縮減傳輸範圍。可減少MPR中多餘的能源消耗。DP-MPR從調整後的傳輸範圍中，可以選出較不靠近邊界的近距離節點，作為負責繼續傳遞廣播封包的節點。因隨意網路節點皆具有移動性，DP-MPR擴增了一段緩衝移動範圍在傳輸範圍上，可防止移動性高的節點在短時間內離開傳輸範圍。因此提高了網路傳輸的穩定度。DP-MPR在調整傳輸範圍時，是利用一些隱藏在Hello Message中的未被MPR所用到的資訊，並未再付出額外的成本來達到目的。在模擬方面，我們使用NS2(Network Simulator) 來和三個廣播方法做比較，“Flooding”、“PAB (Power Adaptive Broadcasting )”及“MPR”。實驗的數據顯示，DP-MPR可節省大部分的電能且可保持很好的網路覆蓋率，並達到很好的網路傳輸穩定度。

Broadcasting of communication technology has been widely adopted in wireless mobile ad hoc networks. The source node can broadcast to find/page the particular mobile host (Mh), or send an alarm message in entire networks. However, the traditional broadcasting, flooding, results in serious redundancy, contention and collision, which we refer as the “broadcast storm problem”. Previous proposed MPR (MultiPoint relays) scheme can resolve this problem by the selection of forwarding node. But it does not concern the mobility and limited supplied power of Mhs. This is because MPR selects forwarding node in the coverage of maximum transmission range. Therefore, the nodes near the border are easily selected as forwarding nodes. Although it can be minimized the number of forwarding nodes but the movement of selected forwarding nodes also easily lead to the disconnection with sender. The goals of existent approaches almost select the border nodes to be forwarding nodes. Therefore, in this thesis we propose a novel broadcasting scheme called DP-MPR (Dynamic Power-aware MultiPoint Relay). DP-MPR defines two MNB conditions (Moving out the Negligible Border node) to dynamically adjust transmission range in order to avoid unnecessary transmission energy. It uses the same selection of MPR from the coverage of adjusted transmission range. It also adds an expanded buffer range on the adjusted transmission range to deal with the movement of selected forwarding node to achieve the stability of propagation. We use NS2 simulator to compare DP-MPR with MPR, simple flooding and PAB (Power Adaptive Broadcasting). The experimental results show our approach can save significantly energy in 20%~25% compared with MPR and also gets higher reachability and efficiency.

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