BUS TOPOLOGY The bus topology is one where a single able connects all computer/nodes (file servers, workstations and peripherals). On the network, the participating nodes communicates over the same bus and one connected through short stub lines to the bus there is no central or host computers used. Each node manages part of the network and messages can be sent from one computer directly to another. Terminating resistor Bus network In the above diagram, it station A intends to send data to station B; the message reaches all connected station. Only station B, processes the dada, all other stations are ignoring it. ADVANTAGES OF BUS NETWORK 1. it is simple, cheap to operate, easy to connect new stations 2. requires less cabling than a star topology. 3. The failures or breakdown of a station does not affect the others in the network. DISADVANTAGES OF BUS NETORK 1. The entire network shuts down it there is a break in the main cable 2. It can be difficult to identify the problem it the entire network shuts down 3. Terminators are required at both end of the main cable. STAR TOPOLOGY Section B Central station Hub Section A The star topology is when each network host is connected to a central hub in LAN called “star” It is a topology where each node is connected directly to central node. Designated computer as central station; message of station A, is forwarded to station B, through the central station. Broadcast network (hub) or point connection switch. ADVANTAGES 1. 2. 3. 4. It is easy to install and wire. One malfunctioning node does not affect the host of the networks. Easy to direct faults and to network parts. No disruption to the network when connecting or rewiring. DISADVANTAGES 1. It requires lots of cabling than bus topology; hence expensive central station is needed. 2. It the central node fails, nodes attached are disable. RING TOPOLOGY This is a topology that is set up in a circular fashion where computers are connected in a single cable with the end nodes also connected to each other. Data travels around the ring in one direction and each device on the right acts as repeaters to keep the signal strong as it travels. This topology uses the token ring technology. Ring topologies are found in some office buildings or school campuses. ADVANTAGES 1. It can be established or spam a large environment than other types such as bus or star. 2. Easy correction of new stations Stations are connected by two opposed rings. DISADVANTAGES 1. A breakdown of one single station can cause complete network failure. 2. It is expensive to set up 3. It the cable breaks, it can cause network failure TREE TOPOLOGY The tree topology is a “hybrid” topology that combines the characteristics of the bus and star topologies. It is a connection of several buses or stars. ADVANTAGES 1. It is a good flexible choice for large computer network, as the tree topology divides the whole network into parts that are more easily manageable. 2. It is easy to expand a network. 3. Minimization of the cable length necessary i.e. the amount of cable used in constructing it is less. 4. It is adaptable to any given geographical structure or zone or area. DISADVANTAGES The online network depends on a central bus and a failure of the central bus can cripple the entire network. MESHED TOPOLOGY This is a topology where nodes are connected with many redundant (alternating) inter connections between network nodes. Every node on the network has a connection to every other node. ADVANTAGES 1. Very long distances can be covered. 2. It is a redundant network, it is hard for the network to fail.