Multihop 行動式無線網路是一種可以在沒有任何有線架構的支援下快速鋪設起來的無線網路。每一個行動節點同時扮演著路由器和用戶端的角色。由於每一個行動節點可能會隨機移動，所以網路中的拓樸關係會快速改變且難以預測。這種形態的網路可被應用在災區通訊、軍事行動以及短期的活動中。
在本篇論文所提的multihop 行動式無線網路中，每個無線頻道都以CDMA技術賦予不同的編碼，且以TDMA將每個頻道劃分為數個slots。

頻寬預留（bandwidth reservation）是在multihop 行動式無線網路中發展QoS控制的基礎。想要在欲建立連線的兩行動節點間進行頻寬預留，就必須在兩行動節點間預留足夠的time slots。本篇論文提出一個新的頻寬預留的方法。此方法可以有效率的找出連線上的頻寬，且可提高頻寬預留的成功率。

本章中提出利用傳遞所有行動節點的free slots資訊到連線路徑末端的方式來計算頻寬。末端的行動節點可利用這些資訊計算路徑上的頻寬並以此決定是否要接受連線要求。此方法名為bottleneck-link-first的計算頻寬的方法。此方法可根據所有行動節點的free slots資訊計算出路徑可預留的最大頻寬的近似值並進行預留的工作。其步驟為：

1.找出所有不重疊的common free slots，將其設為可預留。設為可預留的common free slots數即為該連結目前的頻寬數。

2.尋找目前頻寬最小的連結，若有數個頻寬相同的連結則選總common free slots數最少的連結。

3.在以上所選出的連結中，尋找一個與其他連結common free slots重疊最少的time slot，將其設為可預留。若上一步驟中所選出的連結已無common free slot，則此方法結束。

4.回到步驟2。

本篇論文提出一個在multihop 行動式無線網路上尋找頻寬的新方法。這個方法可以找出頻寬最小的地方並增加其頻寬。這個程序會一直不斷重複直到無法再增加頻寬最小的地方的頻寬。整條路徑上的頻寬即為頻寬最小的連結的頻寬。反覆的模擬結果證實了這個方法較以往單步計算的方法更為優越。

This paper proposes a new method for finding the available
bandwidth of a path in multihop mobile wireless networks.

The proposed method finds the link with the minimum current bandwidth

and increases its bandwidth. This process is repeated until the bandwidth

of the link with the smallest current bandwidth cannot be increased.

Then the available bandwidth of the path is found to be the minimum of

the current bandwidths of the links along the path. Extensive simulations

are performed to compare the performance of the proposed method and that

of the method which calculates the path bandwidth hop by hop.

Our simulation results show that using the proposed method in a

multihop mobile wireless network produces significantly lower call

blocking ratio than the method which calculates the path bandwidth hop by

hop.

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