Title: Instructor's Perspective - Module 10
Course: CGS 1560 Microcomputer Operating Systems > Section: Module 10 - Networking

Module 10: Networking

If you look up the definition of network topology, you will most certainly find that it is how the computers are arranged on a network followed by the types, bus, ring, star, mesh, tree and hybrid. That reference is usually based on a wired network and if they mention wireless networks they try to relate them to the wired network. I think that a little clarification is in order regarding topology and wireless.

Almost every textbook still has bus and ring topologies listed as examples. These are both examples of zombie topologies, meaning that they died then came back to life in the textbooks where they remain. Bus and ring topologies had three limitations that they could not overcome, distance, speed and maximum capacity. These limitations ultimately resulted in their extinction.

The bus topology (IEEE 302.3) was 10Base2 and had a maximum distance of 185 meters, 30 nodes and 10 Mbps speed. 10Base5 was the other bus topology it had a maximum distance of 500 meters, 100 nodes and 10Mbps speed. It was retired from the IEEE working group in 1996. Ring or Token Ring (IEEE 802.5) was retired in 2001; it was limited to a maximum distance of 152 meters, 260 nodes, and 16 Mbps speed. Neither has been used in over a decade. Let them rest in peace.

The main topologies in use today for wired networks are star, mesh, tree and hybrid. Hybrid networks are made up of some combination of star, mesh or tree. Another common misconception is with the wireless networks (IEEE 802.11) being classified as a star because the wireless router or access point is central to the communications. In a wired network your connection is fixed in a wireless network it is not. These wireless topologies are correctly termed point-to-point, point-to-multipoint or mesh. The wireless network is made up of wireless routers, bridges and/or repeaters.

Typically a combination of wired and wireless is found in the business environment and wireless in a home environment. An operating system is adept at operating in either wired or wireless networks. There are limitations associated with any given topology. A sound knowledge of how to setup and manage either type of network is required with the different operating systems. This will allow you to achieve maximum performance within your network.

Attachments

- Mod10_InstructorPerspective.pdf