間歇連結移動網路(ICMNs)是一種無線網路傳輸方式，不需要任何實體的基礎建設或者是集中管理，在ICMNs中的節點就可以互相溝通。然而，由於在ICMNs中的節點會一直移動，一旦兩個溝通中的節點離開彼此的傳輸範圍，連線就會中斷。因此在ICMNs中傳遞封包時，常會因為找不到一個完整的路徑或者是傳到一半路徑中斷了而導致封包無法被接收。當網路環境無法提供接收端無法有一定的機率接收封包時，我們稱這個網路無法提供接收保證(reception guarantees)，而這是ICMNs中的一大挑戰。為了使ICMNs可以提供接收保證，我們使用感染式路由(epidemic routing)作為傳輸封包的方法。感染式路由是基於「儲存與轉發 (store-and-forward)」的特性傳遞封包，因此在提供接收保證的同時，感染式路由也造成大量的緩衝佔用量(buffer occupancy)。因此，降低緩衝佔用量是在ICMNs中使用感染式路由的另外一個挑戰。 在這篇論文中，我們分別針對兩種不同感染式路由的方式進行研究，期望在提供接收保證下分析其效能並降低緩衝佔用量。第一種是全域計時方式(global timeout scheme)，藉由我們發展的數學式，我們可以在指定的接收保證下獲得最佳的全域計時數值及對應的緩衝佔用量。另一種方法是反向封包方式(antipacket dissemination scheme)，反向封包方式可以提供良好的接收保證，而緩衝佔用量可以藉由控制節點是否參與傳遞反向封包而降低。透過我們的研究，可以設計一個良好的感染式路由，以在ICMNs的環境中提供接收保證下，分析並降低緩衝佔用量。

Intermittently connected mobile networks is a type of wireless networks. Nodes in ICMNs can communicate with each other directly without infrastructure and centralized management. Nodes in ICMNs may move to another place with the time goes by, however, once a node is out of connected node's transmission range, the connection between both nodes is interrupt. Therefore, the packet may lose when it is delivered due to the path is changed or interrupt at any time, and we call this network is without reception guarantees since we can't insure whether the destination receive the packet or not. In our work, we use packet loss rate as an indicator of reception guarantees due to packet loss rate can help us to evaluate whether a packet lost or not in a ICMN. Although reception guarantees are big problem in ICMNs, we use epidemic routing as a solution due to its store-and-forward nature. However, in the mean time, epidemic routing also causes excessive buffer occupancy because each nodes received packet store it in their buffer. Therefore, reducing buffer occupancy is another challenge of epidemic routing in ICMNs. Consequently, in our work, we mainly focus on how to design a epidemic routing in ICMNs using less buffer occupancy and with reception guarantees. We analyze and control the performance of two epidemic routing schemes respectively. The first one, in global timeout scheme, we evaluate an equation for obtaining optimal global timeout value with a designed packet loss rate to tradeoff the buffer occupancy and packet loss rate in global timeout scheme. In antipacket dissemination scheme, the buffer occupancy reduces by controlling the participation of relay nodes in transmitting antipacket. Through our work, we can well design a epidemic routing with less buffer occupancy and providing reception guarantees in ICMNs.

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