在無線感測網路中，當網路中傳遞的資料流量超過感測器所能夠負荷的能力時，將會造成網路的擁塞。大部分的無線感測網路應用中，每一個感測器都會將感測到的資料傳遞到匯集節點 (sink)，因此越靠近匯集節點的無線感測器越容易導致網路擁塞。網路擁塞可能會造成封包遺失、頻寬降低和感測器能量的浪費。為了解決無線感測網路擁塞問題，我們提出一個分散式的演算法來減少網路擁塞並且適當分配感測器到匯集節點的資料流量。我們提出的混合式擁塞控制協定不僅考慮在無線感測網路中感測器封包的傳遞速率，也同時考慮感測器緩衝器剩餘的空間，來有效地分配感測器資料流的速率而避免網路擁塞發生。我們的協定可以避免封包由於傳輸擁塞而遺失並且提高網路的流量。藉由模擬結果，我們提出的協定跟以前的文獻比較，亦有較佳的網路效能。

In wireless sensor networks, the congestion occurs when offered traffic load exceeds available capacity of sensor nodes. In most applications, every sensor node will send its sensing event to sink node and result in the sensors closer to the sink experiencing congestion. Congestion may cause packets loss, lower network throughput and waste energy of sensors. To address this challenge, we propose a distributed algorithm that mitigates congestion and allocates appropriate source rate to sink node for sensor networks. The proposed algorithm is a hybrid congestion control protocol which is considered not only the packets delivery rate but remaining buffer size of each node. Our protocol can avoid packets drop due to traffic congestion and improve the network throughput. The simulation results show that the performance of our protocol is better than the previous works.

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