Telecommunications and Networks

Chapter Outline	Key Terms	Study Questions
The Evolution of Networking	telecommunications	What factors have encouraged the growth of networking?
Data Transmission Characteristics		The transmission of data over networks is characterized by what three factors?
Bandwidth	bandwidth bits per second (bps) broadband medium narrowband medium	Explain the difference between a broadband medium and a narrowband medium, and provide examples of each.
Analog and Digital Transmission	analog signal frequency range pitch modem modulation demodulation dial-up modem internal modem external modem Personal Computer Memory Card International Association (PCMCIA) modem	What applications are analog signals used for? What system do computers use to transform data into digital signals? What are two major functions of modems? Explain the difference between an internal modem and an external modem. What is the advantage of each type of modem?
Parallel and Serial Transmission	parity bit serial transmission parallel transmission	Explain the difference between a parallel and serial port. What is the advantage of parallel transmission? What are two common connectors for serial ports?
Communications Media	communications medium	Communications media are classified into what two broad categories?
Wired Communications Media		Why would a user use wired communication media instead of wireless?
Twisted-Pair Cable	twisted-pair cable	What are the advantages of twisted-pair cable?
Coaxial Cable	coaxial cable cable modem	What are the advantages of coaxial cable? What device must be installed to use a cable modem?
Fiber-Optic Cable	fiber-optic cable	What are five advantages of fiber-optic cables? What is the most important advantage of fiber-optic cables?
Integrated Services Digital Network (ISDN)Lines	Integrated Services Digital Network (ISDN) line	What device is required for the use of an ISDN line?
Digital Subscriber Line (DSL)	Digital Subscriber Line (DSL)	What advantage does a DSL offer users who are connected to the Internet?
T Lines	T line T1 line T3 line	What is a major disadvantage of T lines? What are two popular types of T lines? How does a T3 line differ from a T1 line?
Wireless Communications Media		What six types of technology are included under the category of wireless communications media?
Microwave Systems	microwave system	What factor determines the distance between microwave stations? Where are microwave stations usually located and why?
Satellite Systems	communications satellite transponder earth station geosynchronous orbit	Where are communications satellites positioned? Explain how a communication satellite functions. What is an important benefit of satellite systems? For what applications are satellite systems most appropriate?
Infrared Technology	infrared technology	What are three common uses for infrared technology?
Cellular Technology	cellular technology cell wireless service provider (WSP)	How do signals sent by cell phones reach their final destination? With what mobile devices can wireless modems be used?
Wi-Fi Technology	Wi-Fi (802.11 protocol) wireless access point hotspot	What is the most commonly used wireless technology today? How can home networks take advantage of Wi-Fi technology?
Bluetooth Technology	Bluetooth	What are some common uses of Bluetooth technology?
Network Classifications		Into what three categories are networks classified?
Networks Classified by Architecture	network architecture	What are the two major architectural designs for networks?
Client/Server Architecture	client/server architecture client server	What are the proposes of a server? What is a major advantage of a client/server?
Peer-to Peer Architecture	peer-to-peer architecture	What are the advantages and disadvantages of peer-to peer architecture?
Networks Classified by Coverage		What is the difference between local area networks (LANs) and wide area networks (WANs)?
Local Area Networks (LANs)	local area network (LAN) file server print server	What advantages do LANs offer multiple users?
Wide Area Networks (WANs)	wide area network (WAN) metropolitan area network (MAN) public access network (PAN) value added network (VAN) virtual private network (VPN)	What types of organizations are likely to use WANs? What are four major types of WANs? What services are offered by value added networks (VANs)? What well-know service provider is a VAN? What factors make VPNs an attractive option?
Networks Classified by Users		Networks can be classified into what two groups of users?
Intranets	intranet firewall	Why is it difficult for unauthorized users to gain access to an intranet?
Extranets	extranet	Why is it difficult for unauthorized users to gain access to an extranet? Explain how mobile workers can connect with their companies while in the field.
Network Topologies	network topology node	Explain the difference between network topology and the actual wiring path of a network. What are the three common network topologies?
Bus Topologies	bus topology bus transceiver terminator	What do messages sent by the transceiver contain? Explain why problems occur if two or more computers send messages at the same time. What serious problem may occur if there is a broken connection along the bus? What type of cables are used by bus topologies?
Star Topologies	star topology (hub-and-spoke topology)	In star topology, what is the function of the hub? What is the major disadvantage of star topology?
Ring Topologies	ring topology token	What is a potential drawback of ring topologies?
Hybrid Topologies	hybrid topology	Why would businesses choose to use a hybrid topology?
Physical vs. Logical Topologies		Explain the two levels of meaning for the term “typology.” Explain the difference between bus and ring.
Network Hardware		What does setting up a computer network generally require?
Hubs	hub	What is the major function of a hub?
Switches	switch	Why does a network switch render a higher performance than a hub?
Repeaters	repeater (amplifier)	What major advantage does a repeater offer?
Routers	router	What is the purpose of a cable/DSL router?
Gateways	gateway	What two items combine to form a gateway?
Bridges	bridge	What is the major purpose of a bridge?
Network Interface Cards	network interface card (NIC)	What is the most common LAN architecture? What is necessary for a client computer to communicate with another computer?
Network Software	network operating system (NOS)	What is the most important type of networking software? What are the major advantages of Netware?
Communications Software and Protocols		What are the major applications of communications software?
Communications Utilities Features		What three useful features are offered by communications software programs?
Communications Protocols	protocol Open Systems Interconnection (OSI) Reference Model (OSI model)	What are six communications protocols, and what is the purpose of each protocol?
Directional Protocols	simplex transmission half-duplex transmission full-duplex transmission	What are the three possible directions for directional protocols? Explain the differences between simple transmission, half-duplex transmission, and full-duplex transmission.
Asynchronous and Synchronous Transmission Protocols	asynchronous transmission start bit stop bit synchronous transmission synch byte	Explain the differences between asynchronous and synchronous transmission protocols. To communicate with each other, why must computers use the same transmission method?
Local Area Network (LAN) Protocols	Ethernet protocol token ring protocol	A broken ring protocol is used by which networks? Explain how a token can carry both an address and a message.
Wide Area Network (WAN) Protocols	Systems Network Architecture (SNA) polling protocol Feber Distributed Data Interface (FDDI)	What is a major application of FDDI?
Internet and Web Protocols	Transmission Control Protocol/Internet Protocol (TCP/IP) Hypertext Transfer Protocol (HTTP) File Transfer Protocol (FTP)	What is packet switching? What do the letters HTTP indicate? What is a URL? What is an advantage of using FTP?
Electronic Mail Protocols	Simple Mail Transfer Protocol (SMTP) mail server Post Office Protocol (POP) server	Explain how electronic mail is sent and received with SMTP and POP.
Wireless Application Protocols	Wireless Application Protocol (WAP) Internet Protocol (IP) 802.11 protocol 802.11b protocol 802.11a protocol 802.11g protocol 3G	What wireless communication devices allow users to exchange information? What is the major benefit of wireless LANs? What is a major disadvantage of IP? What industry standard is the basis upon which most new wireless devices are being designed and built? What three variations of the 802.11b protocol are widely used? Explain the differences between 802.11a and 802.11b. What is the major advantage of 3G cellular technology?