臺灣博碩士論文加值系統

　　寬頻整體服務數位網路提供了多種的服務，例如聲音、影像、圖片等，它的優點使未來的網路都將朝向它而發展，而非同步傳輸模式正是實現寬頻整體服務數位網路的技術；由於光纖技術發展的成熟，使得在非同步傳輸模式的網路中，交換機的處理能力成為一個瓶頸。
　　縱橫式交換機是一種架構簡單的交換結構，它擁有非阻塞和自我繞路兩項優點，但它的缺點是在一個N×N的交換架構中,其交換點的數目高達N2個，這使得在製作大型交換架構上將耗費相當大的成本，因此，本研究將交換點對映到有限投影平面上，利用有限投影平面的特性，將交換點的複雜度由O（N2）降為O（N□N），同時設計出一個簡單的自我繞路演算法，讓改良式縱橫式交換仍有保自我繞路的優點。
　　由於改良式縱橫式交換機其交換點的減少，造成內部阻塞的產生；在效益評估中，發現埠數在大於169後，對於內部阻塞的機率影響極小，而輸入埠的細胞接收率才是影響內部阻塞的真正因素。

　　The Broadband Integrated Services Digital Network (B-ISDN) offers versatile services such as voice, image and video. Its advantage has motivated growth in B-ISDN. The ATM is a solution for implementing a B-ISDN. The development of optical fiber is very mature. So, In ATM networks the switching, unit has become the bottleneck.
　　Crossbar switch is a very simple switch fabric. Its advantage is non-blocking and self-routing. But, the complexity of switch points is O(N2). That is quite high. So, we map the switch points to the finite projective plane. It can reduce the complexity to O(N□N). we also design a self-routing algorithm that makes the cell from an input port to an output port very quickly.
　　Because the switch points of Modified-crossbar switch decrease, it causes the internal blocking. In performance evaluation, when the port size great than 169, the reflection of internal blocking is very low. The major factor is load.