近年來通訊網路的進步與寬頻網路的發展，使得更多新型的網路服務迅速應運而生，對網路服務的品質(QoS)也更加要求。眾多新興的應用服務中，即時性的應用服務(real-time traffic)，像是Voice over IP (VoIP)以及video on demand (VoD)，對於封包的傳遞延遲時間(delay time)以及抖動(jitter)具有嚴格的要求，router在處理即時性封包時，並非僅將封包快速送出即可，而須在一定的延遲時間內送出。本研究在BBQ﹙Budget-Base QoS﹚的架構下，發展一套簡單而有效的方法，在封包所經過的每一個router時，根據其緊急程度、服務等級及網路處理能力賦予合適的profit function，再對封包重新排程以獲得最大的profit，期望減小在接收端的jitter絕對值總和，進而增進網路的效能。在此我們設計了四種profit function配合Greedy演算法在兩種不同的router架構上調整封包傳送順序，並利用網路模擬工具NS2在即時性訊務分為單一服務等級及雙服務等級的情況下評估我們方法的效能，證明我們的方法較既有的方法更可以有效控制jitter，且能對不同的服務等級做適當的差異化處理以提高整體服務滿意度。 / With fast growth of Internet traffic and applications, real-time streaming applications have attracted significant attention in the current Internet society. Novel real-time Internet applications such as Voice over IP (VoIP) and video on demand (VoD), have stringent delay and jitter requirements. Under these requirements a router not only have to forward real-time packet as fast as possible, it also have to accomplish the job within a time bound. Our research is based on BBQ﹙Budget-Based QoS﹚management architecture. In order to minimize the jitter of real-time services, we propose a new jitter control mechanism that uses per-hop packet scheduling. Four profit function are designed to represent different scheduling preferences. When a packet gets into a router, the router will assign a profit function based on its timeness and the class of service. The scheduler will re-schedule their order in output queue aiming to maximize total profit. Finally we evaluate our proposed mechanism by NS2 simulator in two situations, single real-time service class and two real-time service classes. Simulation results show that by using our approach the performance is better than other approaches. And we investigate the performance of the combination of profit function in handling multiple classes of service.