行動隨意網路是一群無線行動節點的集合，其中無線節點利用點對點的溝通模式以達成自我組織，不需要固定的網路基礎建設或任何集中式管理機制。因為每個節點的無線訊號傳輸範圍是有限的，每個節點必需執行繞徑以達成資料傳遞，並且必須為其他節點轉送控制與資料封包。由於動態拓撲、分散式合作及受限的能力，一個隨意網路只有在參與的節點都以正確的方式合作時，才可以很有效率的運作。換言之所有節點間的合作及正常的資料傳輸變得很重要。
在無線隨意網路中，大部份的繞徑協定假設網路上的節點都是值得信賴且樂意合作的，所以這些繞徑協定並沒有考慮路徑上的中繼節點，可能答應轉送封包，但事實上卻沒有這麼做。我們稱這種情形為資料丟棄行為。因此，整個網路上的產能都將被影響。只有等到繞徑路線因為節點的移動而重建後，此種問題才有機會改善。
因此，我們提出一個新的機制，在適度密集的隨意網路上，減輕資料丟棄攻擊的影響。每一個節點會持續的以監聽模式，監督它的鄰居節點的資料活動，而位在同一條繞徑路線的上、下游節點訊號範圍內的節點，將成為監督者。一但發現鄰居節點沒有協助其上游節點轉送資料封包，則監督者會幫忙傳送此資料封包。當幫鄰居節點重送超過一定次數後，會動態的調整繞徑路線以繞過惡意節點。因此，即使當網路有多個個別或者共謀的攻擊者存在，封包到達率一樣可以維持在一定的比例。

A mobile ad hoc network (MANET) is a collection of wireless mobile nodes that communicate peer-to-peer in a self-organized manner without fixed network infrastructure or any centralized administration. Because the transmission range of each node is limited, each node needs to perform routing in order to delivery and help the neighbor nodes to forward control packets and data packets. With dynamic topology, the distributed cooperation and the constrained capability, MANET can work effectively only if the participating nodes cooperate in a proper way. Therefore, the collaboration among all nodes and normal data transmission become very important.
Most of the routing protocols in MANET assume nodes are trustworthy and cooperative and thus do not consider that the intermediate nodes along a routing path can promise to forward packets but in fact fails to do so. We call this situation packet dropping behaviors. Therefore, the throughput of the whole network will be affected. In original no protected routing protocols, the influence may be mitigated only when the routing path is changed due to the mobility.
In view of this, we propose a novel scheme to mitigate the influence of the packet dropping in the reasonable dense MANET. Each node constantly monitors the traffic activity of its neighbor nodes in the promiscuous mode. A node which located in the signal of the upstream node and the downstream node along a routing path will be a monitor. When any neighbor drops any data packet comes from the upstream node of it, the monitor will help to retransmit the dropped data packet. After the monitor has already helped to retransmit over certain times, it dynamically adjusts the routing path to bypass a misbehavior node Therefore, even when there are many individual or colluded attackers in MANET, the data delivery rate can be hold above certain probabilities.

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