topology Last modified: Wednesday, June 07, 2006
The shape of a local-area network (LAN) or other communications system. Topologies are either physical or logical. There are four principal topologies used in LANs. bus topology: All devices are connected to a central cable, called the bus or backbone. Bus networks are relatively inexpensive and easy to install for small networks. Ethernet systems use a bus topology. ring topology : All devices are connected to one another in the shape of a closed loop, so that each device is connected directly to two other devices, one on either side of it. Ring topologies are relatively expensive and difficult to install, but they offer high bandwidth and can span large distances. star topology: All devices are connected to a central hub. Star networks are relatively easy to install and manage, but bottlenecks can occur because all data must pass through the hub. tree topology: A tree topology combines characteristics of linear bus and star topologies. It consists of groups of star-configured workstations connected to a linear bus backbone cable. These topologies can also be mixed. For example, a bus-star network consists of a high-bandwidth bus, called the backbone, which connects a collections of slower-bandwidth star segments. For network diagrams, see Network Topology Diagrams in the Quick Reference section of Webopedia.
•E-mail this definition to a colleague• For internet.com pages about topology . Also check out the following links! Open Networks Today  Networking news moves at a fast pace, and Open Networks Today lets you keep up with it. Open Networks Today offers its readers the ability to control how news is presented through customizing content filters, discussions, and news feed links. Topologies Understanding the topology of LAN technologies can tell you a lot about your alternatives when installing or expanding a LAN. Yahoo!'s network topology page Yahoo!'s directory of network topology.	Network Topologies 5-4-3 rule bus network cache coherence CAN collapsed backbone Ethernet HAN HPNA HSSI local-area network logical topology mesh physical topology token bus network VSAT Give Us Your Feedback Books topology Products Shop by Top Models: Stephen Willard - General Topology Books 3 store offers from $15 - $46 Mathematics of Fuzzy Sets: Logic, Topology, and Measure Theory 1 store offers from $304 - $304 John W. Milnor - Topology from the Differentiable Viewpoint 2 store offers from $25 - $38 Andrew H. Wallace - Algebraic Topology: Homology and Cohomology 2 store offers from $10 - $12 Michael Monastyrsky - Riemann, Topology, and Physics 1 store offers from $40 - $40