乙太網路可以非常高的速度傳輸資料、可簡單並快速安裝、維護簡單、以及價格低廉的短距離傳輸網路環境，並可選用光纖作為傳輸介質，增加了網路應用的範圍及距離，使得乙太網路非常成功的從區域網路，跨入到城域網路，乃至於廣域網路。以10Gbps或100Gbps為主要核心的光纖乙太網路架構，將會構成下一代網路的骨幹。原本的城域網路及廣域網路都是使用電信網路作為基礎傳輸架構，但基於乙太網路的傳輸速度一直以十倍提昇，但價格卻是一直下降，又因網路傳輸協定的改進，使得利用乙太網路傳輸電信網路資料成為可行。 對於乙太網路一直使用1500Byte的資料長度，也因傳輸的品質、速度越來越高，以傳輸效率來看，加大資料長度換用Jumbo Frame以降低CPU處理能力需求的必要性。 本文主要討論使用光纖乙太網路架構為核心網路，並以其作為分時多工的電信網路基礎傳輸架構，轉換傳統電信語音網路的資料至封包交換式網路，以期望可以架構出便宜、有效率及穩定的乙太網路為基礎的電信傳輸網路，作一分析及探討。 Ethernet is a hierarchical local area data network for high data rate, simplicity relatively short-distance transport, quick installation, easily maintenable, and low cost. Alghough with optical fiber for extened the transport distance to Metro even International connection as transport networks. Ethernet is a permanent success story, extending its reach from LAN and MAN into WAN. 10 Gbps and 100Gbps Ethernet will be the key enabler for a new generation of true end-to-end carrier grade Ethernet networks for carrier the TDM circuits. When the Ethernet frame size is still use 1500Byte since 10Mbps to 10Gbps, but it must rasie up because the transport performance is be lmited with small chunk and required higher performance of network processor. This paper first focuses on functionality and standards required to enable carrier-grade Ethernet-based core networks and possible Ethernet backbone network architechtures will be discussed. The second part then evaluates the TDM circuits over the Ethernet core networks and competitive network architectures. The results propose that Ethernet will not only soon be mature enough for deployment in carrier prvider's backbone networks but also provide huge cost advantages to carrier providers than the original TDM network architectures.
