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CREATED BY :- KONDHIYA SATYAM V. (095270693046)R.K.COLLEGE OF ENGI. AND TECH. -- RAJKOT

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TYPES OF NETWORK TOPOLOGY

INTRODUCTION:-

Topology provides different configurations that are

used to create a network . A network is a group of devicesconnected by communication path to exchangeinformation and share resources . While connectingcomputer together to form a network the use needsconsider a structure , layout and the caballingrequirement.

A network can be created by using point to pointconnection or multi point connection . In point to pointconnection, only two devices are connected to each other.The user can use a point to point connection to transferdata from local network to a remote network through a

dedicated line . Example of point to point connection aremicrowave, satellite and television network. In multipleconnection, many devices share the connection and arecalled as multi drop connection.

Topology can be physical or logical . physicaltopology refers to the actual physical structure of thenetwork , while logical topology determines the way inwhich the data actually passes through the network fromone devices to other.


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Different types of topologies are Single node, Star,Bus , Ring , Mesh , Tree and Hybrid. Physical topologiesare how the wires interconnected , while logical topologyis how the network behaves and interoperates .

1) Bus Topology :In Bus topology devices

share a common backbone cable to send and receivedata. A thick co-axial cable is used to connect alldevices . Bus topology uses daisy chain scheme toadd more devices in a network. In a daisy chainscheme , device 1 is connected to device 2 ; device 2is connected to device 3. The first and last devices are

connected to 50 ohm terminator register.


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Basic Introduction :-In bus topology , the server is

connected at one end of the back bone cable and the otherdevices are connected at different positions along the back bone cable known as trunk. Terminator is placed at eachend of the cable. It is used to unset data (packet) from thecable if the destination devices is faulty . Data is sent toall the devices along the cable. When two machinetransmit data at the same time the signals collide. Due tothis, the information is destroyed . this process is calledcollision. Collision can affect the performance of the

network.


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Advantages :-

1) Easy to connect a device to linear bus.

2) Requires less cable.

3) Less expensive than other topologies.

4) Works better for smaller networks.

Disadvantages :-

1) Entire network gets affected if there is a break in

the main cable.

2) Terminators are requires at both ends of the

backbone cable.

3) Difficult to detect the faulty devices.

4) Limited number of devices can be attached .

5) Heavy traffic and addition of devices degrades the

performance.6) Expensive than single node topology.


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2) Star Topology :-

In star topology, multipledevices are connected to a central connectionpoint known as hub or switch. Devices areattached to the hub by using either copper cablesor fiber optic cables. Star netwoks provide a costeffective method for sharing information

between different user. Star topology can be usedin airlines reservation counter and small businessoffers where employees what an access tocommon application and files.


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Basic Introduction :-

Each devices is connectedpoint to point to a central devices which is either which iseither a hub or switch . Hub manages and controls all thefunction of the network. It also acts as a multi portrepeater for the data flow. Hub is used to connect segment

of LAN and contains multiple ports. Hub can be active orpassive. Passive hub are used as a connection point whichroutes all the traffic towards the devices . Active hubcontains electronics circuits that regenerates andretransmit the information.


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Advantages :-

1) Easy to install, configure and manage.

2) Easy to detect faulty device.

3) Easier to expands.

4) Connecting or removing devices does not affect the

network.

5) Hub provides a centralized management.

Disadvantages:-

1) Increased device causes traffic which makes the

network slow.2) Requires move cable length than a linear topology.

3) Hub failure leads to networks failure.

4) More expensive.


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The ring topology is used to

implement the token ring network at 4 or 16 Mbps . intoken ring network, a special single or a small messagecalled token is continually passed from one device toanother. The devices which has the token is allowed totransmit data over the network. The nodes on a Token-Ring are connected electrically or optically in ringstructure. But physically they are always connected in astar configuration to hub which is also asMAU( Multistation Access Unit )


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Advantages:-

1) Easier to manage as compared to Bus Network.

2) Handles large volume of traffic.

3) Very reliable and offers great speed.

4) Provides a good communication over a long distance.

5) No terminator are required .

Disadvantages :-

1) More cable wires compared to bus topology are

required.

2) One faulty devices affected the entire network.

3) Addition and charge of devices can affect the

network.


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4) Mesh Topology :-In mesh topology , every

devices is connected to each and every node in thenetwork with many redundant interconnection at leasttwo paths to and from every node. There are twotypes of mesh topologies , full mesh and partial mesh.In full mesh topology , each device is connecteddirectly to each other . in partial mesh topology some

of the devices are connected to all the other.


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There are some deviceswhich do not exchange data with all. So they areconnected only to those with which they communicatemost of the time . it is less expensive and less redundantcompared to full mesh topology. This topology is useful

where connection are easily and frequently broken.


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Advantages :-

1) Provide redundant path which help in sending data

using an alternate path if a specific path fails to send

the data.

2) Entire network does not get affected by one faulty

device.

3) Centralized management is not required as in startopology.

4) Easy to detect faulty devices .

Disadvantages :-

1) More cabling is required as compared to BUS ,STARand RING topologies.

2) Each link from one device to another requires anindividual NIC.

3) Very expensive as compared to BUS, STAR, andRING topologies.

4) Data carrying capability is under utilized unless alldevices are transmitting almost constantly .

5) Difficult to reconfigure.

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