隨著網路技術的進步，網路流量也日益劇增。不斷增加的網路行為帶來越來越多
的網路攻擊。為了保護網路的考靠境及安全性，網路監控變得變得重要。軟體定
義網路 (Software Defined Networks,SDN) 將網路區分成控制平面及數據平面並使
用SDN控制器來控制整個網路，相較於傳統網路SDN的流量監控管理更加的靈活
彈性。
然而，在軟體定義網路中可用來做網路監控的資源是有限的，例如交換機
的性能，在監控任務增加的情況下，會影響數據平面流量傳輸的效能。本論文
中我們改進了現有的平衡網路監控任務分配的方法，我們考慮到冷門節點，並
將網路流量重新路由，確保網路上的每個節點都能參與監控並分配監控任務。
我們改進的方法和使用Gurobi optimizer進行最佳化分配的結果比較，我們在可
接受的網路監控平衡程度中，有較好的執行時間。平均重新路由的時間可以提
高200到400倍，而分配時間也有10到30倍的提升。

With the advancement of network technology, network traffic is also increasing rapidly.
Increasing network behavior has brought more and more network attacks. In order to
protect the network’s accessibility and security, network monitoring has become important. Software Defined Networks (SDN) divides the network into a control plane and a
data plane and uses the central controller to control the entire network. Compared with
traditional network , SDN’s traffic monitoring and management are more flexible.
However, the resources available for network monitoring in SDN are limited, such
as the performance of switches. As monitoring tasks increase, the performance of data
plane traffic transmission will be affected. In order to balance the method of network
monitoring task distribution, we considered unpopular nodes and rerouted network traffic
to ensure that each node participated in monitoring and assigned monitoring tasks. Compared with the Gurobi optimizer, the simulation results show that we have better execution
time within an acceptable network monitoring balance. The average rerouting time can
be 200 to 400 times faster, and the distribution time can be 10 to 30 times faster.

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