信息與通信工程專業(yè)介紹(英文版)(1)

1、Brief Introduction to Information and Communication Engineering 2011.5.30Brief Introduction to Information and Communication EngineeringvAmong all of the essentials for human existence, the need to interact with others ranks just below our need to sustain life. Communication is almost as important t

2、o us as our reliance on air, water, food, and shelter. vThe methods that we use to share ideas and information are constantly changing and evolving. Whereas the human network was once limited to face-to-face conversations, media breakthroughs continue to extend the reach of our communications. From

3、the printing press to mobile phone, each new development has improved and enhanced our communication.The development of Communication（1）In ancient times ，information could be transferred through light or sound。 光通信：中國-烽火臺、希臘火炬的位置表示字母符號聲通信：中國擊鼓鳴金（2）Beginning and turning point：1837-Morse-telegram；1876

4、-Bell-telephone；1895-Marconi-radioThe development of Communicationvdevelopment of transmission channel multicore cableCoaxial Cableoptical fiber 多芯電纜同軸電纜光纖vdevelopment of Communication components vacuum tubetransistorintegrate circuitlarge scale integrated circuit 真空管晶體管集成電路大規(guī)模集成電路vdevelopment of tr

5、ansmission method telegram voice Much carrier modulationpulse - code modulation 電報(bào)-聲音多載波調(diào)幅pcmvdevelopment of range of message voice text graph， image 聲音文字圖形、圖像 The development of CommunicationvAs with every advance in communication technology, the creation and interconnection of robust data networks

6、 is having a profound effect. vEarly data networks were limited to exchanging character-based information between connected computer systems. Current networks have evolved to carry voice, video streams, text, and graphics between many different types of devices. Previously separate and distinct comm

7、unication forms have converged onto a common platform. This platform provides access to a wide range of alternative and new communication methods that enable people to interact directly with each other almost instantaneously. The future of Communication（3）5w：whatever wherever whoever whomever whenev

8、er 任何人在任何時(shí)間、任何地點(diǎn)接收來自任何人的任何信息The future of Communication Mobile Cellular NetworkMobile Cellular Network Mobile Ad Hoc Network Fixed NetworkFixed Network BSC BSC BSC WLANWLANWhat is Communication？vAs we all know，networks can support the way we learn，the way we work and the way we play.Living in a netw

9、ork-centric world,communication is an essential part of our lives.What is Communication？v Communication in our daily lives takes many forms and occurs in many environments. Each situation has its corresponding expected behaviors and styles. vEstablishing the Rules Before beginning to communicate wit

10、h each other, we establish rules or agreements to govern the conversation. These rules, or protocols, must be followed in order for the message to be successfully delivered and understood. Among the protocols that govern successful human communication are:vAn identified sender and receivervAgreed up

11、on method of communicating (face-to-face, telephone, letter, photograph)vCommon language and grammarvSpeed and timing of deliveryvConfirmation or acknowledgement requirements Ensure Quality of CommunicationsvCommunication between individuals is determined to be successful when the meaning of the mes

12、sage understood by the recipient matches the meaning intended by the sender. vThe external factors affecting communication are related to the complexity of the network and the number of devices a message must pass through on its route to its final destination.Ensure Quality of CommunicationsvInterna

13、l factors that interfere with network communication are related to the nature of the message itself. vBoth the internal and external factors that affect the receipt of a message must be anticipated and controlled for network communications to be successful. New innovations in network hardware and so

14、ftware are being implemented to ensure the quality and reliability of network communications.Communication over NetworksvBeing able to reliably communicate to anyone, anywhere, is becoming increasingly important to our personal and business lives. In order to support the immediate delivery of the mi

15、llions of messages being exchanged between people all over the world, we rely on a web of interconnected networks. These data or information networks vary in size and capabilities, but all networks have four basic elements in common:vRules or agreements to govern how the messages are sent, directed,

16、 received and interpretedvThe messages or units of information that travel from one device to anothervA means of interconnecting these devices - a medium that can transport the messages from one device to anothervDevices on the network that exchange messages with each other The Elements of a Network

17、vThe diagram shows elements of a typical network, including devices, media, and services, tied together by rules, that work together to send messages. The Elements of a Network：devicesThe Elements of a Network：devicesvSwitch - the most common device for interconnecting local area networksvFirewall -

18、 provides security to networksvRouter - helps direct messages as they travel across a network vWireless Router - a specific type of router often found in home networksThe Elements of a Network：mediumThe Elements of a Network：mediumvFor a network to function, the devices must be interconnected. Netwo

19、rk connections can be wired or wireless. In wired connections, the medium is either copper, which carries electrical signals, or optical fiber, which carries light signals. In wireless connections, the medium is the Earths atmosphere, or space, and the signals are microwaves. The Elements of a Netwo

20、rk：rulesvHuman beings often seek to send and receive a variety of messages using computer applications; these applications require services to be provided by the network. Some of these services include the World Wide Web, e-mail, instant messaging, and IP Telephony. Devices interconnected by medium

21、to provide services must be governed by rules, or protocols. In the chart, some common services and a protocol most directly associated with that service are listed. The Elements of a Network：rulesThe Elements of a Network：messagesvIn the first step of its journey from the computer to its destinatio

22、n, our instant message gets converted into a format that can be transmitted on the network. All types of messages must be converted to bits, binary coded digital signals, before being sent to their destinations. This is true no matter what the original message format was: text, video, voice, or comp

23、uter data. Once our instant message is converted to bits, it is ready to be sent onto the network for delivery.The Elements of a Network：messageschannelMultiple services-multiple networksvTraditional telephone, radio, television, and computer data networks each have their own individual versions of

24、the four basic network elements. In the past, every one of these services required a different technology to carry its particular communication signal. Additionally, each service had its own set of rules and standards to ensure successful communication of its signal across a specific medium.Multiple

25、 services-multiple networksConverged Networks Technology advances are enabling us to consolidate these disparate networks onto one platform - a platform defined as a converged network. The flow of voice, video, and data traveling over the same network eliminates the need to create and maintain separ

26、ate networks. On a converged network there are still many points of contact and many specialized devices - for example, personal computers, phones, TVs- but only one common network infrastructure. Converged NetworksWhat is required for us？vConverged networks, which carry all communications types (da

27、ta, voice, and video) on one infrastructure, provide an opportunity to reduce costs and offer users feature-rich services and content. However, the design and management of converged networks requires extensive networking knowledge and skills if all services are to be delivered as expected to users.vDifferent types of