| Compared with the traditional best-effort service, the incoming IP traffic such as multimedia applications and multicast applications are undergoing great changes. They demand not only huge amount of the bandwidth but also strict end-to-end delay guarantees. Therefore, particular QoS control mechanism as well as new Internet service mode should be introduced. This thesis focuses on the research of QoS architecture and implementation mechanism for broadband access network. Since Ethernet Passive Optical Network (EPON) emerges to be a promising candidate for the next-generation broadband access networks, all the study in this thesis will be based on the EPON transmission platform. The content of the thesis is organized into four parts as follows.The first part discusses two service models concerned with IP QoS and their realization. As a per-flow oriented QoS architecture, IntServ model is just fit for edge networks with small scale. To achieve end-to-end QoS, an IntServ-oriented EPON QoS architecture is proposed, which includes three key function modules: resource reservation, packet scheduling and bandwidth allocation. Although EPON's protocol IEEE 802.3ah is standarded by modifying and expanding IEEE 802.3, the point-to-multipoint structure is quite different from the point-to-point Ethernet. Based on SBM (Subnet Bandwidth Manager) protocol and EPON architecture, an improved SBM named SOEP (SBM Over EPON) is proposed to implement IntServ model in EPON. It redefines the managed EPON segment, offers solutions to the election of the DSBM and the establishment of the per-hop path, etc. Moreover, it substitutes LLID-based soft state refreshment for traditional RSVP session-based refreshment, which increases the scalability of state refreshment as well as reduces protocol overhead. To decreases message loss probability, four new messages are created in SOEP to achieve acknowledgement and retransmission scheme. Finally, the perfect...
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