Summary

Chapter 8: Fundamental Networks 29■Single-mode is cable that has a very thin core. It is harder to make, uses lasers as alight source, and can transmit signals dozens of kilometers with ease.A fiber-optic cable is one or more optical fibers enclosed together in a sheath or jacket.Describe LAN Topologies and ArchitecturesMost of the computers that you work on will be part of a network. Topologies and architecturesare building blocks for designing a computer network. Although you may not build acomputer network, you need to understand how they are designed so that you can work oncomputers that are part of a network.The two types of LAN topologies are physical and logical. A physical topology, shown inFigure 8-19, is the physical layout of the components on the network. A logical topology,shown in Figure 8-20, determines how the hosts communicate across a medium, such as acable or the airwaves. Topologies commonly are represented as network diagrams.Figure 8-19Physical TopologyA LAN architecture is built around a topology. A LAN architecture comprises all the componentsthat make up the structure of a communications system. These components includethe hardware, software, protocols, and sequence of operations.After completing this section, you will meet these objectives:■■Describe LAN topologies.Describe LAN architectures.