ATM模擬框架與模擬輔助環境

Abstract

ATM為新一代的網路技術，具有高頻寬、低延遲、容納多樣網路服務的能力。在ATM網路發展的過程中，必須歷經通訊協定驗證之程序以確認該通訊協定功能與效能的正確性。對於龐大且複雜的ATM通訊協定，要進行其驗證是一件困難的工作，因此適當的驗證流程對於ATM通訊協定而言是相當重要的。 ATM通訊協定的驗證可分為三個階段︰靜態驗證分析、動態驗證分析、實際量測。其中動態驗證方法是在模擬環境下以軟體模擬的方式執行通訊協定製作以進行參數的量測與驗證工作，可以幫助通訊協定設計人員及早發現大部分原來只能在最後實際製作階段中才能發現的錯誤，甚至連原來難以發現的錯誤，設計人員也可以在較容易受控制的模擬環境中發現。 為輔助通訊協定設計人員完成動態驗證所需之模擬程式，本研究設計一個以ATM模擬程式框架為基礎的模擬輔助環境，利用組合元件的方式完成所需之模擬程式。ATM模擬程式框架（稱為ATM模擬框架）定義了ATM模擬程式的軟體架構及其內部共同（共用）類別，利用此框架，設計人員可採以下兩種擴充方式得到所需之模擬程式：1) override pre-defined methods 2) plug in software components。ATM模擬輔助環境建構於ATM模擬框架之上，提供一個Visual Programming的設計環境，讓設計師能夠利用設計完成的元件組合出所需要的模擬程式，並能針對特殊需求設計新的元件；藉此提供設計師更快、更有效率的方式完成動態驗證所需要的模擬程式。

As a new network technology, ATM has the transmission capability of high bandwidth and low delay to serve multiple network service. In the process of ATM protocol development, verification must be performed to insure the functionality and performance of the protocol. Since ATM protocols are so large and complicated that their verification is difficult to be performed, proper verification process is important to ATM protocol development. ATM Protocol verification can be divided into three stages: static analysis, dynamic analysis, and physical measurement. Dynamic analysis is the method that simulates the execution process and measures the verification parameters of the protocol within the simulation environment. Under the controlled simulation environment, protocol designers can find most errors that can only be observed in physical measurement and even the errors that are hard to observe. To help protocol designers completing the simulation program for dynamic analysis, we design a simulation environment based on the framework of ATM simulation programs to provide designers with a component-based construction approach for constructing simulation programs. The framework of ATM simulation programs, called ATM simulation framework, defines the software architecture and the common classes of ATM simulation programs. Designers may extend ATM simulation framework to derive required simulation programs by following approaches : 1) override pre-defined methods 2) plug in software components. ATM simulation framework is the infrastructure of ATM simulation environment. ATM simulation environment provides a visual programming environment which allows designers to compose a simulation program with designed components and to design new components for some specific requirements. With the assistance of ATM simulation environment, designers are able to complete the simulation programs for dynamic analysis more efficiently and more effectively.