基本信息
- 原书名：Computer Networking and the Internet
- 原出版社： Addison Wesley
编辑推荐
本书讲解透彻，深入浅出，是一部非常成功的网络技术教科书，不仅适合作为计算机、通信、电子工程等专业本科生和研究生的教材，而且适合相关技术人员参考使用。
内容简介
书籍
计算机书籍
随着万维网的出现，全球性质的因特网已经快速发展成为计算机网络的主导类型。除了提供基本的电子邮件和IP电话服务外，因特网还可以利用网页为全世界的人们提供电子商务和各种娱乐服务。因此，对计算机网络的研究实际上就是对因特网及其应用的研究。
本书是一部非常成功的网络技术教科书，第5版经过完全修订，删除了过时的网络协议和网络架构，重点介绍因特网。目前，因特网技术发展突飞猛进，许多因特网应用涉及多种数据类型 (文本、图像、语音、音频和视频) ，因此本书还详细地讲述了怎样表示这些数据类型。本书讲解透彻，深入浅出，不仅适合作为计算机、通信、电子工程等专业本科生和研究生的教材，而且适合相关技术人员参考使用。
本书特点
●采用了大量的图表以及实例，使复杂的系统以及知识点一目了然。
●内容翔实，覆盖面广，从数据通信和互联网基础知识到因特网的应用，从局域网、无线网到因特网协议，从电子商务到网络安全。
●紧跟最新的技术发展潮流，详细讲解了与当前技术发展密切相关的网络知识，反映了计算机网络领域的最新进展，增加了因特网最新的技术内容。
●提供了丰富的学习资源的在线指南，可查看www.pearsoned.co.uk/halsall。
计算机书籍
随着万维网的出现，全球性质的因特网已经快速发展成为计算机网络的主导类型。除了提供基本的电子邮件和IP电话服务外，因特网还可以利用网页为全世界的人们提供电子商务和各种娱乐服务。因此，对计算机网络的研究实际上就是对因特网及其应用的研究。
本书是一部非常成功的网络技术教科书，第5版经过完全修订，删除了过时的网络协议和网络架构，重点介绍因特网。目前，因特网技术发展突飞猛进，许多因特网应用涉及多种数据类型 (文本、图像、语音、音频和视频) ，因此本书还详细地讲述了怎样表示这些数据类型。本书讲解透彻，深入浅出，不仅适合作为计算机、通信、电子工程等专业本科生和研究生的教材，而且适合相关技术人员参考使用。
本书特点
●采用了大量的图表以及实例，使复杂的系统以及知识点一目了然。
●内容翔实，覆盖面广，从数据通信和互联网基础知识到因特网的应用，从局域网、无线网到因特网协议，从电子商务到网络安全。
●紧跟最新的技术发展潮流，详细讲解了与当前技术发展密切相关的网络知识，反映了计算机网络领域的最新进展，增加了因特网最新的技术内容。
●提供了丰富的学习资源的在线指南，可查看www.pearsoned.co.uk/halsall。
作译者
作者：(英国)哈尔索尔
目录
Chapter 1 Data communications and networking basics
1.1 Overview
1.2 Application and networking terminology
1.3 Digital communication basics
1.4 rotocol basics
1.5 Protocol stacks
Summary
Exercises
Chapter 2 Telephone networks and modems
2.1 Introduction
2.2 Transmission systems
2.3 Access network signaling
2.4 Trunk network signaling
2.5 Broadband modems
2.6 Internet service providers
Summary
Exercises
Chapter 3 Local area networks and intranets
3.1 Introduction
3.2 Ethernet / IEEE 802.3
1.1 Overview
1.2 Application and networking terminology
1.3 Digital communication basics
1.4 rotocol basics
1.5 Protocol stacks
Summary
Exercises
Chapter 2 Telephone networks and modems
2.1 Introduction
2.2 Transmission systems
2.3 Access network signaling
2.4 Trunk network signaling
2.5 Broadband modems
2.6 Internet service providers
Summary
Exercises
Chapter 3 Local area networks and intranets
3.1 Introduction
3.2 Ethernet / IEEE 802.3
译者序
文艺复兴以降，源远流长的科学精神和逐步形成的学术规范，使西方国家在自然科学的各个领域取得了垄断性的优势；也正是这样的传统，使美国在信息技术发展的六十多年间名家辈出、独领风骚。在商业化的进程中，美国的产业界与教育界越来越紧密地结合，计算机学科中的许多泰山北斗同时身处科研和教学的最前线，由此而产生的经典科学著作，不仅擘划了研究的范畴，还揭橥了学术的源变，既遵循学术规范，又自有学者个性，其价值并不会因年月的流逝而减退。
近年，在全球信息化大潮的推动下，我国的计算机产业发展迅猛，对专业人才的需求日益迫切。这对计算机教育界和出版界都既是机遇，也是挑战；而专业教材的建设在教育战略上显得举足轻重。在我国信息技术发展时间较短、从业人员较少的现状下，美国等发达国家在其计算机科学发展的几十年间积淀的经典教材仍有许多值得借鉴之处。因此，引进一批国外优秀计算机教材将对我国计算机教育事业的发展起积极的推动作用，也是与世界接轨、建设真正的世界一流大学的必由之路。
机械工业出版社华章图文信息有限公司较早意识到"出版要为教育服务"。自1998年开始，华章公司就将工作重点放在了遴选、移译国外优秀教材上。经过几年的不懈努力，我们与Prentice Hall，Addison-Wesley，McGraw-Hill，Morgan Kaufmann等世界著名出版公司建立了良好的合作关系，从它们现有的数百种教材中甄选出Tanenbaum，Stroustrup，Kernighan，JimGray等大师名家的一批经典作品，以"计算机科学丛书"为总称出版，供读者学习、研究及庋藏。大理石纹理的封面，也正体现了这套丛书的品位和格调。
"计算机科学丛书"的出版工作得到了国内外学者的鼎力襄助，国内的专家不仅提供了中肯的选题指导，还不辞劳苦地担任了翻译和审校的工作；而原书的作者也相当关注其作品在中国的传播，有的还专程为其书的中译本作序。迄今，"计算机科学丛书"已经出版了近百个品种，这些书籍在读者中树立了良好的口碑，并被许多高校采用为正式教材和参考书籍，为进一步推广与发展打下了坚实的基础。
随着学科建设的初步完善和教材改革的逐渐深化，教育界对国外计算机教材的需求和应用都步入一个新的阶段。为此，华章公司将加大引进教材的力度，在"华章教育"的总规划之下出版三个系列的计算机教材：除"计算机科学丛书"之外，对影印版的教材，则单独开辟出"经典原版书库"；同时，引进全美通行的教学辅导书"Schaum's Outlines"系列组成"全美经典学习指导系列"。为了保证这三套丛书的权威性，同时也为了更好地为学校和老师们服务，华章公司聘请了中国科学院、北京大学、清华大学、国防科技大学、复旦大学、上海交通大学、南京大学、浙江大学、中国科技大学、哈尔滨工业大学、西安交通大学、中国人民大学、北京航空航天大学、北京邮电大学、中山大学、解放军理工大学、郑州大学、湖北工学院、中国国家信息安全测评认证中心等国内重点大学和科研机构在计算机的各个领域的著名学者组成"专家指导委员会"，为我们提供选题意见和出版监督。
这三套丛书是响应教育部提出的使用外版教材的号召，为国内高校的计算机及相关专业的教学度身订造的。其中许多教材均已为M．I．T.，Stanford，U．C．Berkeley，C．M．U．等世界名牌大学所采用。不仅涵盖了程序设计、数据结构、操作系统、计算机体系结构、数据库、编译原理、软件工程、图形学、通信与网络、离散数学等国内大学计算机专业普遍开设的核心课程，而且各具特色--有的出自语言设计者之手、有的历经三十年而不衰、有的已被全世界的几百所高校采用。在这些圆熟通博的名师大作的指引之下，读者必将在计算机科学的宫殿中由登堂而入室。
权威的作者、经典的教材、一流的译者、严格的审校、精细的编辑，这些因素使我们的图书有了质量的保证，但我们的目标是尽善尽美，而反馈的意见正是我们达到这一终极目标的重要帮助。教材的出版只是我们的后续服务的起点。华章公司欢迎老师和读者对我们的工作提出建议或给予指正，我们的联系方法如下：
电子邮件：h2JsJ@hzbook．com
联系电话：(010)68995264
联系地址：北京市西城区百万庄南街l号
邮政编码：100037
近年，在全球信息化大潮的推动下，我国的计算机产业发展迅猛，对专业人才的需求日益迫切。这对计算机教育界和出版界都既是机遇，也是挑战；而专业教材的建设在教育战略上显得举足轻重。在我国信息技术发展时间较短、从业人员较少的现状下，美国等发达国家在其计算机科学发展的几十年间积淀的经典教材仍有许多值得借鉴之处。因此，引进一批国外优秀计算机教材将对我国计算机教育事业的发展起积极的推动作用，也是与世界接轨、建设真正的世界一流大学的必由之路。
机械工业出版社华章图文信息有限公司较早意识到"出版要为教育服务"。自1998年开始，华章公司就将工作重点放在了遴选、移译国外优秀教材上。经过几年的不懈努力，我们与Prentice Hall，Addison-Wesley，McGraw-Hill，Morgan Kaufmann等世界著名出版公司建立了良好的合作关系，从它们现有的数百种教材中甄选出Tanenbaum，Stroustrup，Kernighan，JimGray等大师名家的一批经典作品，以"计算机科学丛书"为总称出版，供读者学习、研究及庋藏。大理石纹理的封面，也正体现了这套丛书的品位和格调。
"计算机科学丛书"的出版工作得到了国内外学者的鼎力襄助，国内的专家不仅提供了中肯的选题指导，还不辞劳苦地担任了翻译和审校的工作；而原书的作者也相当关注其作品在中国的传播，有的还专程为其书的中译本作序。迄今，"计算机科学丛书"已经出版了近百个品种，这些书籍在读者中树立了良好的口碑，并被许多高校采用为正式教材和参考书籍，为进一步推广与发展打下了坚实的基础。
随着学科建设的初步完善和教材改革的逐渐深化，教育界对国外计算机教材的需求和应用都步入一个新的阶段。为此，华章公司将加大引进教材的力度，在"华章教育"的总规划之下出版三个系列的计算机教材：除"计算机科学丛书"之外，对影印版的教材，则单独开辟出"经典原版书库"；同时，引进全美通行的教学辅导书"Schaum's Outlines"系列组成"全美经典学习指导系列"。为了保证这三套丛书的权威性，同时也为了更好地为学校和老师们服务，华章公司聘请了中国科学院、北京大学、清华大学、国防科技大学、复旦大学、上海交通大学、南京大学、浙江大学、中国科技大学、哈尔滨工业大学、西安交通大学、中国人民大学、北京航空航天大学、北京邮电大学、中山大学、解放军理工大学、郑州大学、湖北工学院、中国国家信息安全测评认证中心等国内重点大学和科研机构在计算机的各个领域的著名学者组成"专家指导委员会"，为我们提供选题意见和出版监督。
这三套丛书是响应教育部提出的使用外版教材的号召，为国内高校的计算机及相关专业的教学度身订造的。其中许多教材均已为M．I．T.，Stanford，U．C．Berkeley，C．M．U．等世界名牌大学所采用。不仅涵盖了程序设计、数据结构、操作系统、计算机体系结构、数据库、编译原理、软件工程、图形学、通信与网络、离散数学等国内大学计算机专业普遍开设的核心课程，而且各具特色--有的出自语言设计者之手、有的历经三十年而不衰、有的已被全世界的几百所高校采用。在这些圆熟通博的名师大作的指引之下，读者必将在计算机科学的宫殿中由登堂而入室。
权威的作者、经典的教材、一流的译者、严格的审校、精细的编辑，这些因素使我们的图书有了质量的保证，但我们的目标是尽善尽美，而反馈的意见正是我们达到这一终极目标的重要帮助。教材的出版只是我们的后续服务的起点。华章公司欢迎老师和读者对我们的工作提出建议或给予指正，我们的联系方法如下：
电子邮件：h2JsJ@hzbook．com
联系电话：(010)68995264
联系地址：北京市西城区百万庄南街l号
邮政编码：100037
前言
Objectives
Prior to the introduction of the World Wide Web, there were many different types of computer networks used to interconnect geographically distributed sets of computers. Many large corporations and businesses, for example, often used proprietary networks, each with its own protocols and networking infrastructure, while, at the same time, the Internet was used primarily to interconnect distributed sets of computers that were located at academic and research institutions around the world. Typical applications were electronic mail and more general file transfers between computers.
With the advent of the Web, however, since the Internet was the networking infrastructure used for the Web, the Internet has rapidly become the dominant computer network as people at home and at work started to use the Web. Typical applications are interactive entertainment, electronic commerce, and so on, which, of course, are in addition to the standard applications already supported by the Internet. As we can deduce from this, therefore, the subject of computer networking is now synonymous with the study of the Internet and its applications.
The combined effect of these developments means that the number of users of the Internet has expanded rapidly. To support this expansion, instead of most users accessing the Internet through an academic network, a number of different types of access network are now used. For example, most users at home and in small businesses gain access through their local switched telephone network using either a Iow bit rate modem or, more usually, a broadband modem. Alternatively, for cable television subscribers, access is often through a high bit rate cable modem. In practice, however, both access methods provide only a physical connection to a second network called an Internet service provider (ISP) network. This, as its name implies, provides the access point to the Internet for a set of users that fall within the field of coverage of a particular ISP network. Clearly, therefore, there are many ISPs each of which is a private, commercial company and hence access to the Internet through an ISP must be paid for.
In addition to telephone and cable networks, with the introduction of Internet-enabled mobile phones and laptops with radio interfaces, many users on the move now gain access to the Internet using a regional/national/international cellular phone network? All of these different types of access network are in addition, of course, to the conventional site networks used by large corporations and businesses. Because of the importance of the Web to their businesses, most of these site networks now use the same protocols as the Internet to facilitate inter working with it.
In many instances, the expanding range of applications supported by the Internet has come about through the technological advances in the way the user data associated with these applications is represented. For example, until relatively recently, a number of the access networks that are now used, in addition to providing their basic service such as telephony, only supported applications in which the application data was composed of text comprising strings of alphanumeric characters entered at a keyboard. As a result of the technological advances in the area of compression, however, the same access networks can now support a much richer set of applications involving multiple data types. These include, in addition to text, digitized images, photos/pictures, speech, audio and video.
As we can deduce from this brief overview, to study the technological issues relating to computer networking and the Internet requires an in-depth understanding not only of the operation of the Internet itself but also the operation of the different types of access network that are used and how they interface with the Internet. In addition, because many of the applications involve the transfer of sensitive information, the topic of security is now essential when describing the operation of the Internet. The aim of this book is to provide this body of knowledge. To do this, the book is divided into two logical parts. The first - Chapters 1 through 5 - is concerned with the fundamentals of digital transmission and communication protocols together with descriptions of the mode of operation of the different types of access network that are now used and how they interface with the global Internet. The second - Chapters 6 through 10 - describes the architecture and communication protocols used by the Internet and the applications that it supports. In addition, the second part describes the techniques that are used to ensure that all the data relating to these applications are transferred in a secure way-
The book has five appendices. In Appendix A we present descriptions of how the different types of data used in the various Internet applications are represented together with an overview of the operation of the compression algorithms that are employed with text, digitized images, photos/pictures, speech, audio and video.
As we shall explain, when transmitting digital data over a network, bit corruptions/errors are often introduced. Hence in Appendix B we describe a number of the different methods that are used to detect the presence of transmission/bit errors in a received block of data.
Normally, when a bit error within a block of data is detected, another copy of the block is requested by the receiving device. In some instances, however - for example when data is being transmitted over a radio/wireless link - the frequency of bit errors is such that the request message for a new copy of a corrupted block may also be corrupted and hence an alternative approach must be used. This involves adding significantly more what are called error control bits. These are added in such a way that the receiver can use them to deduce what the original data block contained. This approach is called forward error control and an introduction to this topic is given in Appendix C.
Wireless networks - that is, networks that use radio as the transmission medium - are now widely used in a number of access networks. In Appendix D, therefore, we give a short introduction to the subject of radio propagation and transmission so that the standards relating to this type of network can be understood.
As we shall see, the global Internet is composed of many thousands of networks that are organized into hierarchical layers. At the higher layers, the networks must route data through them at very high rates and are called backbone networks. In Appendix E we describe the technology that is used to achieve these very high switching rates.
Intended readership
The book has been written primarily as a course textbook for both university and college students studying courses relating to the technical issues associated with computer networking based on the Internet, its protocols and applications. Typically, the students will be studying in a computer science, computer systems, computer engineering or electronic engineering department/ school. In addition, the book is suitable for computer professionals and engineers who wish to build up a working knowledge of this rapidly evolving subject. At one extreme this requires the reader to understand the techniques that are used to transmit a digital bitstream over the different types of transmission medium, such as copper wire, coaxial cable, radio and optical fiber. At the other extreme it requires an understanding of the software that is used in the different types of equipment - personal computers, workstations, laptops, mobile phones, set-top boxes, etc. - that are used to support Internet applications. The first is the domain of the electronics engineer and the secondof the computer scientist. Care has been taken, however, to ensure that the book is suitable for use with courses for both types of student by ensuring that the level of detail required in each subject area is understandable by both categories of reader.
In order to achieve this goal, an introductory chapter has been included that describes the basic hardware and software techniques that are used to achieve the reliable transfer of a block/stream of digital data over a transmission channel. These include the different methods that are used to detect the presence of transmission errors - bit corruptions - in a received block/stream of data and the procedures that are followed to obtain another copy of the block/stream when this occurs. The latter form what is called a communications protocol, Hence this chapter also includes an introduction to the subject of protocols to give the reader who has no previous knowledge of this subject the necessary foundation for the later chapters that describe the operation of the different types of access networks and the protocols and applications of the Internet.
Intended usage
To the instructor
As we can see from the list of contents, the book covers a range of topics each of which is to a depth that makes it interesting and academically challenging. As a result, the book can be used for a number of different courses relating to computer networking and the Internet. Ideally, in order to obtain an indepth technical understanding of the subject area, a set of courses should be used to collectively cover the total contents of the book from the principles of data communications through to details of the different types of access networks and the protocols and applications of the Internet. Alternatively, it can be used for one or two courses each of which covers a subset of this subject area. For example, one course may cover the basics of digital communications and an overview of the operation of the different types of access network that are used with the Internet. The second course can then cover the architecture and detailed operation of the Internet and its protocols together with its applications including the World Wide Web and the topic of security. The book is considered to be suitable for both undergraduate and taught masters courses.
As indicated earlier, all of the topics are covered to a depth that enables the reader to build up an in-depth technical understanding of the subject. Hence because of the technical nature of the subject, to help the reader to understand each topic within an area, either a worked example or a relatively detailed diagram is used to illustrate the concepts involved. This is considered to be one of the main advantages of the book over competing texts owing to the technical detail associated with many of the diagrams. Also, both the examples and diagrams are seen as being particularly useful for instructors as they can be used directly for lectures. To facilitate this, therefore, both the worked examples and all the diagrams are available to instructors in their electronic form so reducing considerably the time required to prepare a set of lectures for a course. These can be downloaded from www. booksites, net/halsaU. In addition, each chapter has a comprehensive set of exercises that have been structured to help the student to revise the topics covered in that chapter in a systematic way.
To the student
Prior to the introduction of the World Wide Web, there were many different types of computer networks used to interconnect geographically distributed sets of computers. Many large corporations and businesses, for example, often used proprietary networks, each with its own protocols and networking infrastructure, while, at the same time, the Internet was used primarily to interconnect distributed sets of computers that were located at academic and research institutions around the world. Typical applications were electronic mail and more general file transfers between computers.
With the advent of the Web, however, since the Internet was the networking infrastructure used for the Web, the Internet has rapidly become the dominant computer network as people at home and at work started to use the Web. Typical applications are interactive entertainment, electronic commerce, and so on, which, of course, are in addition to the standard applications already supported by the Internet. As we can deduce from this, therefore, the subject of computer networking is now synonymous with the study of the Internet and its applications.
The combined effect of these developments means that the number of users of the Internet has expanded rapidly. To support this expansion, instead of most users accessing the Internet through an academic network, a number of different types of access network are now used. For example, most users at home and in small businesses gain access through their local switched telephone network using either a Iow bit rate modem or, more usually, a broadband modem. Alternatively, for cable television subscribers, access is often through a high bit rate cable modem. In practice, however, both access methods provide only a physical connection to a second network called an Internet service provider (ISP) network. This, as its name implies, provides the access point to the Internet for a set of users that fall within the field of coverage of a particular ISP network. Clearly, therefore, there are many ISPs each of which is a private, commercial company and hence access to the Internet through an ISP must be paid for.
In addition to telephone and cable networks, with the introduction of Internet-enabled mobile phones and laptops with radio interfaces, many users on the move now gain access to the Internet using a regional/national/international cellular phone network? All of these different types of access network are in addition, of course, to the conventional site networks used by large corporations and businesses. Because of the importance of the Web to their businesses, most of these site networks now use the same protocols as the Internet to facilitate inter working with it.
In many instances, the expanding range of applications supported by the Internet has come about through the technological advances in the way the user data associated with these applications is represented. For example, until relatively recently, a number of the access networks that are now used, in addition to providing their basic service such as telephony, only supported applications in which the application data was composed of text comprising strings of alphanumeric characters entered at a keyboard. As a result of the technological advances in the area of compression, however, the same access networks can now support a much richer set of applications involving multiple data types. These include, in addition to text, digitized images, photos/pictures, speech, audio and video.
As we can deduce from this brief overview, to study the technological issues relating to computer networking and the Internet requires an in-depth understanding not only of the operation of the Internet itself but also the operation of the different types of access network that are used and how they interface with the Internet. In addition, because many of the applications involve the transfer of sensitive information, the topic of security is now essential when describing the operation of the Internet. The aim of this book is to provide this body of knowledge. To do this, the book is divided into two logical parts. The first - Chapters 1 through 5 - is concerned with the fundamentals of digital transmission and communication protocols together with descriptions of the mode of operation of the different types of access network that are now used and how they interface with the global Internet. The second - Chapters 6 through 10 - describes the architecture and communication protocols used by the Internet and the applications that it supports. In addition, the second part describes the techniques that are used to ensure that all the data relating to these applications are transferred in a secure way-
The book has five appendices. In Appendix A we present descriptions of how the different types of data used in the various Internet applications are represented together with an overview of the operation of the compression algorithms that are employed with text, digitized images, photos/pictures, speech, audio and video.
As we shall explain, when transmitting digital data over a network, bit corruptions/errors are often introduced. Hence in Appendix B we describe a number of the different methods that are used to detect the presence of transmission/bit errors in a received block of data.
Normally, when a bit error within a block of data is detected, another copy of the block is requested by the receiving device. In some instances, however - for example when data is being transmitted over a radio/wireless link - the frequency of bit errors is such that the request message for a new copy of a corrupted block may also be corrupted and hence an alternative approach must be used. This involves adding significantly more what are called error control bits. These are added in such a way that the receiver can use them to deduce what the original data block contained. This approach is called forward error control and an introduction to this topic is given in Appendix C.
Wireless networks - that is, networks that use radio as the transmission medium - are now widely used in a number of access networks. In Appendix D, therefore, we give a short introduction to the subject of radio propagation and transmission so that the standards relating to this type of network can be understood.
As we shall see, the global Internet is composed of many thousands of networks that are organized into hierarchical layers. At the higher layers, the networks must route data through them at very high rates and are called backbone networks. In Appendix E we describe the technology that is used to achieve these very high switching rates.
Intended readership
The book has been written primarily as a course textbook for both university and college students studying courses relating to the technical issues associated with computer networking based on the Internet, its protocols and applications. Typically, the students will be studying in a computer science, computer systems, computer engineering or electronic engineering department/ school. In addition, the book is suitable for computer professionals and engineers who wish to build up a working knowledge of this rapidly evolving subject. At one extreme this requires the reader to understand the techniques that are used to transmit a digital bitstream over the different types of transmission medium, such as copper wire, coaxial cable, radio and optical fiber. At the other extreme it requires an understanding of the software that is used in the different types of equipment - personal computers, workstations, laptops, mobile phones, set-top boxes, etc. - that are used to support Internet applications. The first is the domain of the electronics engineer and the secondof the computer scientist. Care has been taken, however, to ensure that the book is suitable for use with courses for both types of student by ensuring that the level of detail required in each subject area is understandable by both categories of reader.
In order to achieve this goal, an introductory chapter has been included that describes the basic hardware and software techniques that are used to achieve the reliable transfer of a block/stream of digital data over a transmission channel. These include the different methods that are used to detect the presence of transmission errors - bit corruptions - in a received block/stream of data and the procedures that are followed to obtain another copy of the block/stream when this occurs. The latter form what is called a communications protocol, Hence this chapter also includes an introduction to the subject of protocols to give the reader who has no previous knowledge of this subject the necessary foundation for the later chapters that describe the operation of the different types of access networks and the protocols and applications of the Internet.
Intended usage
To the instructor
As we can see from the list of contents, the book covers a range of topics each of which is to a depth that makes it interesting and academically challenging. As a result, the book can be used for a number of different courses relating to computer networking and the Internet. Ideally, in order to obtain an indepth technical understanding of the subject area, a set of courses should be used to collectively cover the total contents of the book from the principles of data communications through to details of the different types of access networks and the protocols and applications of the Internet. Alternatively, it can be used for one or two courses each of which covers a subset of this subject area. For example, one course may cover the basics of digital communications and an overview of the operation of the different types of access network that are used with the Internet. The second course can then cover the architecture and detailed operation of the Internet and its protocols together with its applications including the World Wide Web and the topic of security. The book is considered to be suitable for both undergraduate and taught masters courses.
As indicated earlier, all of the topics are covered to a depth that enables the reader to build up an in-depth technical understanding of the subject. Hence because of the technical nature of the subject, to help the reader to understand each topic within an area, either a worked example or a relatively detailed diagram is used to illustrate the concepts involved. This is considered to be one of the main advantages of the book over competing texts owing to the technical detail associated with many of the diagrams. Also, both the examples and diagrams are seen as being particularly useful for instructors as they can be used directly for lectures. To facilitate this, therefore, both the worked examples and all the diagrams are available to instructors in their electronic form so reducing considerably the time required to prepare a set of lectures for a course. These can be downloaded from www. booksites, net/halsaU. In addition, each chapter has a comprehensive set of exercises that have been structured to help the student to revise the topics covered in that chapter in a systematic way.
To the student
