在非同步傳輸網路中使用頻譜分析的訊務控制

Abstract

隨著科技的快速進步, 寬頻整合服務數位網路將是未來的主流.在其中 , 非同步傳輸模式將會在服務傳輸上被採用. 此非同步傳輸模式網路最大 的優點是在於它可彈性地收容各種不同的服務. 然而, 每一件被收容的 服務都必須滿足其服務品質. 若我們接受太多服務於網路上, 這服務品 質就可能受損. 因此, 本篇論文研究如何在滿足服務品質的條件下, 而 能到達最佳的系統使用率, 我們將研究利用輸入訊務的功率頻譜, 設計 一個在呼叫層的訊務控制, 就是允諾控制, 此外, 我們也提出一個在細 胞層且具雙參考值和部份拒絕的訊務控制, 也就是阻塞控制, 並定義了 一個效能準則來評估整體系統效能, 同時, 我們也以此效能準則找出最佳 之阻塞階段值. With the rapid development of technology, B-ISDN (Broadband Integrated Services Digital Networks) will be the main trend in the future. Among other things, the ATM (Asynchronous Transfer Mode) will be adopted in service transmission. The main advantage of an ATM network is the flexibility of accommodating verstile services, however, all the quality of services on the network must satisfy the QOS required by service providers. If we accept too many services, the QOS may be corrupted. Hence, this paper studies how to achieve high system utilization under the constraint of QOS. We use the power spectrum of the input traffic to design a call-layer traffic control, i.e., call admission control. In addition, we also propose a two-threshold congestion control with partial rejection at cell layer. We define a performance criterion for the evaluation of the overall system utilization. Also, we use this performance criterion to find the optimal levels setting for the congestion control.