一個無線隨意行動網路(mobile ad hoc network) 是由一群mobile hosts所組成，彼此之間不須經由基地台的幫助而有能力做相互的溝通。本篇論文主要是探討如何在mobile ad hoc network上具有服務品質(QoS)中"頻寬要求"的繞徑問題，這對現行很多的即時多媒體應用是非常重要的。現存的資訊大都在探討如何找出uni-path到目的端。所以我們提出藉由on-demand協定找出從來源端到目的端具有"頻寬要求"的多重路徑(multi-path)。最基本的想法是從來源端發出一些ticket ，每一張ticket負責找出從來源端到目的端符合頻寬要求的路徑。每一張ticket在遇到只走一條Link頻寬不足時，可以被分割成sub-ticket ，分送到不同的link，用來幫助找出足夠頻寬的多重路徑(multi-path)。藉由模擬的結果，我們可以證明多重路徑協定具有以下的優點 : (i) 當網路的頻寬比較小時，多重路徑(multi-path)比利用uni-path可以提供較高的成功率找到符合服務品質(QoS)的路徑，(ii)當網路的頻寬足夠時，多重路徑(multi-path)的效能與利用uni-path的方式是不相上下的。

A mobile ad hocnetwork (MANET) is one consisting of a set of mobile hosts capable
of communicating with each other without the assistance of base stations. This paper
considers the QoS (quality-of-service) routing problem in a MANET, which is important for
many real-time multimedia applications. We propose an on-demand protocol for searching
for a multi-path QoS route from a source host to a destination host in a MANET, where a
multi-path is a network with a source and a sink satisfying certain bandwidth requirement.
Existing works all try to nd a uni-path to the destination. The basic idea is to distribute
a number of tickets from the source, which can be further partitioned into sub-tickets to
search for a satisfactory multi-path. Through simulations, we justify that the value of our
multi-path protocol is on its exibility: (i) when the network bandwidth is very limited, it
can oer a higher success rate to nd a satisfactory QoS route than those protocols which
try to nd a uni-path, and (ii) when the network bandwidth is suAcient, it can perform
almost the same as those protocols which try to nd a uni-path (in both routing overhead
and success rate).

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