信息保障与安全.doc

This book focuses on two broad areas: cryptographic algorithms and protocols, which have a broad range of applications; and network and Internet security, which rely heavily on cryptographic techniques. 这本书主要集中在两大领域：加密算法与协议，具有广泛的应用范围；网络和网络安全，这很大程度上依赖于加密技术。 Cryptographic algorithms and protocols can be grouped into four main areas: 加密算法与协议可以分为四个主要部分： Symmetric encryption: Used to conceal the contents of blocks or streams of data of any size, including messages, files, encryption keys, and passwords. 对称加密：用来隐藏任何大小的数据块和数据流，包括消息、文件、加密密钥和密码。 Asymmetric encryption: Used to conceal small blocks of data, such as encryption keys and hash function values, which are used in digital signatures. 非对称加密：用来隐藏小数据块，如加密密钥和散列函数值，这是用于数字签名。 Data integrity algorithms: Used to protect blocks of data, such as messages, from alteration [,?:lt?‘rei??n]. 数据完整性算法：通常保护数据块，比如信息的变化。 Authentication protocols: These are schemes based on the use of cryptographic algorithms designed to authenticate the identity of entities. 认证协议：这些都是基于密码算法设计实体的身份认证方案的使用。 10 09 2. COMPUTER SECURITY: The NIST Computer Security Handbook [NIST95] defines the term computer security as follows: The protection afforded to an automated information system in order to attain the applicable objectives of preserving the integrity, availability, and confidentiality of information system resources (includes hardware, software, firmware固件, information/ data, and telecommunications通信). This definition introduces three key objectives that are at the heart of computer security: 计算机安全： NIST计算机安全手册[ nist95 ]计算机安全术语定义如下： 给一个自动保护信息系统以达到保存完整，适用的目标的可用性，必威体育官网网址的信息系统资源（包括硬件、软件、固件、信息、数据和通信）。这个定义了计算机安全核心的三个关键目标： 1) Confidentiality(机密性，必威体育官网网址性): Preserving authorized restrictions on information access and disclosure, including means for protecting personal privacy and proprietary information. A loss of confidentiality is the unauthorized disclosure of information. This term covers two related concepts: Data confidentiality: Assures that private or