正常而言，對於建置于單一控管單位之下隨意式網路中的節點，它們一定會分享自己的資源以傳遞通訊協定訊息或是協助封包轉送。然而，對於並非由特定單位建立的隨意式網路而言，我們不能保證網路裡的節點會提供網路協同工作的相關服務。事實上，那些拒絕協同工作的節點可以因此節省能源，使本身的執行時間更為持久。尤其是當我們注意到那些沒有分享自己資源的節點還是可以利用其它正常節點的資源以達到其目的時，此類問題更能突顯其嚴重性。
在這篇論文裡面，我們提出一種可使節點免於遭受利用的機制。此機制乃是根據節點本身觀察所得的資訊以計算每個相鄰節點的重要程度；每個節點根據上述的重要程度對其相鄰節點分配單位時間之內願意為其轉送封包的數量。
模擬結果顯示採用此機制的節點能夠有效地避免遭到利用。而且，此類節點根據重要程度動態地拒絕協助轉送封包的方式不但讓網路效能僅受到輕微之影響，亦能節省可觀的資源。在整體網路自私節點比例略低時，網路效能的下降是為了追求公平而採取動態拒絕協助轉送封包的必然結果，然而在整體網路自私節點比例增加的同時，我們的機制反而呈現了比沒有此機制更好的網路效能。因此若一隨意式網路採用本機制將會可達到不被自私節點利用之公平運作環境，且在相同的網路效能之下，將可以大幅地降低各節點所需付出之系統資源。

Normally, nodes cooperate with each other in a mobile ad hoc network in which it is under the administration of a single authority. Each node contributes resources to route discovery and packet forwarding. However, in case of civilian applications such as network of cars, the nodes may not belong to a single authority and not pursue a common goal. In such cases, nodes are not forced to cooperate, thus the network functions are not guaranteed. Instead of forwarding packets for others, a node exploits resources of others and contributes nothing, which results in lower power consumption and longer operation time. Indeed, the situation may be severe since the resources (battery power, memory, bandwidth, and CPU cycles) each node owns are extremely limited.
This thesis proposes a mechanism which provides the node in a mobile ad hoc network the capability of preventing from being exploited by selfish neighborhood. The mechanism relies on the observed information to determine each neighbor’s importance according to different metrics. After that, the flow rate allocated for each neighbor is figured out based on its importance level respectively.
The simulation results show that no packet is forwarded when they are originated from selfish nodes. Besides, only few packets are failed to achieve its destination while respectable amount of forwarding operations are saved on average. The simulation results also show that when the percentage of selfish nodes in the network is small, the network throughput is affected due to fairness consideration. Once the percentage of selfish nodes increases, our mechanism makes the network throughput better compared to the original network.

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