Data Communications Networking Devices: Operation, Utilization and Lan and Wan Internetworking, 4th Edition

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LAN INTERNETWORKING DEVICES

In the first four chapters of this book we became familiar with networking fundamentals, obtaining an overview of the characteristics of different types of networks and a general appreciation for the operation and utilization of several networking devices. Using that knowledge we will now begin to examine networking devices in detail. In this chapter we will focus our attention upon a core series of devices used to interconnect LANs that can be separated by a short cabling distance or that are located thousands of miles from one another … thus, the title of this chapter.

Devices we will examine in this chapter include what many persons refer to as the Three Musketeers of LAN internetworking—bridges, routers, and gateways. Although these devices play an important role in LAN internetworking, they are not the only products that provide users with the ability to access a local area network. Thus, we will also examine the operation and utilization of several additional internetworking devices in this chapter. Those additional devices include access servers, LAN switches, and several types of communications servers. While a Frame Relay Access Device (FRAD) can be considered to represent a LAN internetworking device, it also represents a communications product that can concentrate data from several network devices. Therefore we will defer a discussion of the operation and utilization of FRADs until Chapter 6 when we cover data communications concentration ...