臺灣博碩士論文加值系統

寬頻 (broadband) 與保障服務品質 (Quality of Service, QoS) 已成為網路發展的兩股重要趨勢，多重協定標籤交換 (Multiprotocol Label Switching, MPLS) 技術近年來發展相當迅速，它不僅可增加現有網際網路上封包的傳輸速度，更具有利於發展訊務工程 (traffic engineering) 的優點。網際網路所提供之整合服務 (Integrated Service, IntServ) 可讓使用者依其要求的服務品質順暢地傳輸具時間敏感性的資訊，而達成服務品質保障的目的。
本論文旨在研究多重協定標籤交換與整合服務的結合，透過標籤交換路由器 (Label Switching Router, LSR) 聚集資料流，並針對此整合服務資料流預留適當資源，在網際網路上有效率地保障服務品質。透過聚集整合服務資料流同時可解決整合服務不適用於較大型網路之擴充性 (scalability) 的問題。控制負載型服務 (controlled-load service) 與保證型服務 (guaranteed service) 為整合服務的兩種服務型態，針對此兩種服務的特性，我們用不同的策略來服務此聚集後的資料流。針對聚集後之控制負載型服務資料流，我們使用簡單的先到先服務 (First Come First Serve, FCFS) 的排程機制，而針對聚集後之保證服務資料流，則採改良式的輪換優先權佇列 (Rotating Priority Queue +, RPQ+) 做為排程的方法。
我們參照美國的very High Speed Backbone Network Service (vBNS) 與臺灣的學術網路 (Taiwan Academic Network, TANet) 做為模擬用之兩種網路架構。模擬的結果顯示，由於資料流的聚集，在相同的頻寬下可以容納更多的服務，同時也解決了整合服務的擴充性問題。

It is commonly believed that Integrated Service (IntServ) is not scalable to large networks. In this thesis, we study the association of Multiprotocol Label Switching (MPLS) and IntServ to try to overcome the scalability problem. The goal is to provide Quality of Service (QoS) in an efficient and scalable manner in the Internet through enable Label Switching Routers (LSRs) to be able to identify the appropriate reservation state for the aggregated IntServ flows based on the corresponding label. IntServ data flows are aggregated and mapped to one data flow in the MPLS network. IntServ data flows belong to the same Forwarding Equivalence Class (FEC) are aggregated.
The proposed scheme of integration of IntServ and MPLS is efficient and scalable. Efficiency implies that when flow aggregation is employed, one can use less resource to achieve the same required QoS, and less time is spent in transmitting packets. Scalability means that the aggregation of IntServ flows makes IntServ works well even when the volume of the data flow becomes huge. Controlled-load service and guaranteed service are two service types of IntServ. According to the different characteristic of these two services, First Come First Serve (FCFS) and the Rotating Priority Queue+ (RPQ+) packet scheduling are employed for aggregated controlled-load and guaranteed-service flows, respectively.
The Taiwan Academic Network (TANet) and very High Speed Backbone Network Service (vBNS) are used as our simulation environments. Simulation results show that because of flow aggregation, more flows could be served meanwhile the scalability problem of IntServ is also mitigated.

Chapter 1 Introduction 1
1.1 Current IP level QoS Solutions: IntServ and DiffServ 2
1.2 Motivation and Goal 8
Chapter 2 Supporting IntServ in the MPLS Network 11
2.1 Multiprotocol Label Switching 11
2.2 Network Architecture 16
2.3 Procedures of Supporting IntServ in MPLS Networks 18
2.4 Flow Aggregation 20
Chapter 3 Packet Scheduling and Resource Management 23
3.1 Packet Scheduling for Controlled-Load Service 23
3.2 Resources Management for Controlled-Load Service 24
3.3 Packet Scheduling for Guaranteed Service 30
3.4 Resource Management for Guaranteed Service 32
Chapter 4 Simulation Results 39
4.1 Simulation Environment 39
4.2 Simulation Results 41
Chapter 5 Conclusion 45
References 47

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