NETWORK TOPOLOGY

network topology

what is network topology ?

• network topology is the layout of the computers and devices in a communications network.

Different between bus, star and ring topology

BUS TOPOLOGY

bus topology is a consists of a single central cable (backbone) , to which all computers and other devices connected.

Advantages of bus network

• Inexpensive and easy to install
• other devices can be attached or detached without disturbing the network
• failure of one device usually does not affect the rest of the network

Disadvantages of bus network

• there might be disruption when computer or other devices are added or removed
• the break in the main cable (backbone) will prevent all systems from accessing the network
• it is difficult to identify the problem if the entire network shut down

STAR TOPOLOGY

Star topology is all the computers and other devices on the network connect to a central device, thus forming a star.

Advantages of star network

• If one device fails, only that device is affected
• devices can be added or removed from network with no disruption
• easy to troubleshoot and isolate problem

Disadvantages of star network

• If the hub or switch fails, the entire network will be inoperable
• Requires more cables than most of the other topology
• More expensive because of the cost of hub or switch

RING TOPOLOGY

Ring topology is a cable forms a closed loop(ring) with all computers and devices arranged along the ring.

Advantages of ring network

• transmission of data is simple as packets travel in one direction only
• cabel faults are easily located, making troubleshooting easier
• all devices in ring topology share the network resources fairly

Disadvantages of ring network

• A failure in any cable or device breaks the loop and can take down entire network
• data packets must pass through every computer, thus make it slower
• more difficult to install than a bus network

Classification of Network
  
Different between LAN,MAN and WAN

CRITERIA	LAN	MAN	WAN
Area of coverage	Network cover limited area such as closely positioned group of buildings network, network at home, network office in building.	A high speed network that connects Local Area Network in a Metropolitan Area such as a cities or town.	Network cover large geographical area such a countries, the continent or the world.
Network size	Small size (in a building)	Larger size (in a cities or a campus)	Larger size (different states or countries)
Speed	Fastest in data transferring and access time	Slower in data transferring and access time	Slowest in data transferring and access time
Examples	-Network inside the computer lab -Network around school -Network inside your home	-Surveillance system -Traffic light monitoring system -Cable network TV	-Car navigation system -Video conference -Intelligent transportation sytem (ITS)
Communication devices	Connected using modems, hub , switch , router	Connected using modems, hubs, switch , router	The connection is made via satellite communication link or via internet
Cost	Less cost	More costly	Costliest
Network ownership	Private	Private	Not owned up any organization but exist under collective or disributed ownership