Bus network topology
The bus topology is an old one and essentially has each of the computers on the network daisy-chained to each other and you can see if computer #1 sends a packet to computer #4, it must pass through computers #2 and #3, creating excess traffic.
Advantages: Cheap, easy to set up.
Disadvantages: A failure may affect many users and problems are difficult to troubleshoot.
Star network topology
The star topology uses twisted pair (10baseT or 100baseT) cabling and requires that all devices are connected to a hub.
Advantages: centralized monitoring and failures do not affect others unless it is the hub. It is easy to modify.
Disadvantages: If the hub fails then everything connected to it is down.
Ring network topology
The ring topology looks the same as the star, except that it uses special hubs and ethernet adapters. The ring topology is used with Token Ring networks.
Advantages: Equal access.
Disadvantages: Difficult to troubleshoot and network changes or failures affect many users.
Hybrid network topology
Hybrid topologies are combinations of the above and are common on very large networks. For example, a star bus network has hubs connected in a row (like a bus network) and has computers connected to each hub as in the star topology.
Mesh network topology
In a true mesh topology every node has a connection to every other node in the network. A full mesh network can be very expensive, but provides redundancy in case of a failure between links.
Wireless network topology
Wireless networks allow computers to comunicate without the use of cables. IEEE 802.11b defines two pieces of equipment, a wireless station, which is usually a PC or a Laptop with a wireless network interface card (NIC), and an Access Point (AP), which acts as a bridge between the wireless stations and Distribution System (DS) or wired networks. An 802.11b wireless network adapter can operate in two modes, Ad-Hoc and Infrastructure. In infrastructure mode, all your traffic passes through a wireless access point. In Ad-hoc mode, your computers talk directly to each other and do not need an access point at all. 802.11b delivers data throughput of 11 Mbps and 802.11g runs at 54mbps.
Advantages: World-wide acceptance. Ranges over 150 feet. Freedom to move about and no cables needed.
Disadvantages: Susceptible to interference from objects such as microwave ovens, cordless phones, etc.
