Summary

The following points summarize the main elements of this chapter:

		The physical layout of computers on a network is called a topology.
		There are four basic topologies: star, bus, ring, and mesh.
		Topologies can be physical (actual wiring) or logical (the way they work).
		In a bus topology, the computers are connected in a linear fashion on a single cable.
		Bus topologies require a terminator on each end of the cable.
		In a star topology, the computers are connected to a centralized hub.
		Mesh topologies connect all computers in a network to one another with separate cables.
		Hubs are used to centralize the data traffic and localize failures. If one cable breaks,
		it will not shut down the entire network.
		The data is segmented into pieces, addressed, and then encoded on the media.
		The transport layer links the network support layers (physical, data link, and network
		layers) and the user support layers (session, presentation, and application layers).
		The physical layer coordinates the functions required to transmit a bit stream over a physical medium.
		The data link layer supports delivering data units without errors from a device to another.
		The network layer is responsible for the routing of data (packets) through the network;
		handles the addressing and delivery of data

Summary

		The transport layer is responsible for delivering a message from a process to process.
		The session layer coordinates session between devices over the network.
		The presentation layer defines the format used to exchange data among communicating devices.
		The application layer provides a means for the user to access information on the network
		through an application.