隨著網路上流動的資料量增多，網路的連線速度也必須隨之提升。乙太網路(Ethernet)是在本區地域網絡(local area network)最普遍被使用的一種協定，而在廣域區域網絡(wide area network)中部建10億級位元速度的乙太網路(Gigabit Ethernet)也正在進行中。同步光纖網路(SONET)這個已存在的基本的架構提供了有效率、可信賴的資料傳輸能力。利用同步光纖網路來傳輸乙太網路的訊框(Ethernet-over-SONET, EoS)成了既可保有乙太網路的簡單特性，又融合了同步光纖網路的有效率的一個選擇。
我們實作了一個有新穎架構的EoS映射器(mapper)，在實體端(physical side)能夠連接24個乙太網路埠，而在線路端(line side)能夠提供四個OC-12的介面。加上引入了鏈路容量調整機制(LCAS)和虛擬串聯(VCAT)，我們的設計還有如下的特點，如：動態頻寬調整，新的封包與成員的對應機制，以及消除了延遲時間差(differential delay)的問題

As data traffic has stepped up enormously, the network speed has to be raised up. Ethernet is the most popular protocol deployed in local area networks (LANs) while deploying the Gigabit Ethernet (GbE) to the wide area networks (WANs) is moving on and on. SONET, an exited telecommunication infrastructure, provides efficient, reliable data transportation capability. Ethernet-over-SONET (EoS) becomes one choice to haul the packets while keeping the Ethernet’s simplicity and SONET’s efficiency.
We implement an EoS mapper with novel architecture. It is able to provide 24 Ethernet ports at the physical side and quad OC-12 rate at line side. With LCAS and VCAT, many features are achieved, such as dynamic bandwidth adjustment, new packet-member mapping scheme, moreover, the differential delay problem is eliminated.

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