对照ISO/OSI参考模型各个层中的网络安全服务，在物理层可以采用(53)加强通信线路的安全；在数据链路层，可以采用(54)进行链路加密；在网络层可以采用(55)来处理信息内外网络边界流动和建立透明的安全加密信道；在传输层主要解决进程到进程间的加密，最常见的传输层安全技术有(56)等；为了将低层次安全服务进行抽象和屏蔽，最有效的一类做法是可以在传输层和应用层之间建立中间件层次实现通用的安全服务功能，通过定义统一的安全服务接口向应用层提供(57)安全服务。

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Originally, the World-Wide Web was designed as information medium for(71) research teams. A deliberately simple implementation model was chosen to make it as simple as possible for authors to(72) documents to the web, and to(73)these in the sense of updating content. This implementation model is centered around the notion of resources, usually file-based. For the (74)intended use of the web, resources presented a useful abstraction, as they related to relatively self-contained chunks of information such as research publications and (75) pages. Such chunks of information typically could be set up and maintained independently of other resources, so that resources were the appropriate abstraction for composition and modification.

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UML-based tools are often used for J2EE/.NET application analysis and design，both because UML's object orientation is ideal for the J2EE/.NET implementation(66) and because of the expanding scope and complexity of today's enterprise endeavors．(67) the approaches diverge at the coding/implementation phase，a common Set of analysis and design techniques applies to both J2EEand.NET．

 The use of a virtual machine (VM) architecture is also common to J2EE and .NET. Application development tools(68) intermediate-level code instead of platform-specific binary code, which means the VM interprets that code in real time or performs Just-In-Time (JIT) compilation; the Microsoft VM always runs JIT-compiled code. This VM-based model results in(69)-independent applications and is conducive to the late-binding technique that's(70) to the OO approach.