Networking TopologyA topology refer to both physical and logical layout of network. The physical topology refer to actual layout of network devices. Physical topology should not be confused with logical topology which is method used to pass information between workstation. There are six type of Topology.

1.BUS Topology2.RING Topology3.STAR Topology4.MESH Topology5.FDDI Topology6.TREE Topology7.HYBRID Topology

BUS TopologyA BUS topology uses a trunk or backbone to which all of the computer on the network connect. System connect to this backbone using “T” type connector terminators. This topology require terminator for both side of backbone to avoid signal reflection. Commonly used for implementing Ethernet at 10 Mbps. Using Coaxial cable during the 1980 and early 1990. It has more segment.

Backbone

ADVANTAGE

1.Easy to implement2.Low Cost3.Easy to connect4.Require less cable.

DISADVANTAGE

1.Entire network shut down if there is break in main cable.2.Terminator are require both side.3.Difficult the problem if entire network shut down.

Ring Topology

The ring Network is a part of topology. In this Network all massage travel in a same direction. This type network is wired in a serial circuit a failure in any cable or device break the loop and can take down the entire network. All PC are connected in a Ring circle. There are no terminated in end.The method by which the data is transmitted around the ring is called token ring passing. IBM token ring uses this method. In the token ring network use Multistations access unit (MSAU) is equipment to a hub or Switch on Ethernet network.

Ring Topology

Token Ring Topology

ADVANTAGE

1.Cable faulty are easily located , Making troubleshoot easier.2.Ring network are moderately easy to install.

DISADVANTAGE

1.Expansion to the network can cause network disruption.2.A single break in the cable can disrupt the entire network.

STAR TOPOLOGY

In the star network all the computers and other network devices connected with central Device called HUB or SWITCH. Each connected require a single cable to connected to HUB. Creating point to point connection between hub or network device. It has require more cable. Generally UTP cable are used( Unshielded twisted pair).The star topology is most widely implemented network design in use today.

HUB

ADVANTAGE

1.Easy to implement and extend even in large network.2.Well suitable for temporary network.3. Security can be implemented in the HUB/Switch.

DISADVANTAGE

1.It has limited cable and length and number of station.2.Maintence costs may be higher in long run.3.Failure of central node can be disturb all network.

Mesh TopologyIn the mesh topology each computer are connected with each other by separate cable. Create point to point connection to every device on network. If one cable fail data always has alternative path to get to its destination.On a large scale, you can connect multiple LANs using mesh topology with leased line.This type topology generally use in military area.

Advantage

1.Provide redundant path between device.2. The network can be expanded without disruption to current user.

Disadvantage

1. Require more cable then other topology .2. Complicated implementations.

FDDI TopologyThe American national Standard s Institute (ANSI) developed the fiber distribution Data Interface.(FDDI) standard in the mid -1980s to meet the growing need for a reliable and fast networking system to accommodate distributed application. Its data transfer speed is 100 Mbps and higher.

ADVANTAGE

1. High speed data transfer2. Easy to connect.

DISADVANTAGE

1. Need costly equipment.2. Dual ring Design.

TREE TopologyTree Topology integrated multiple star topologies together onto bus. In its design only HUB / Switch device connect directly to the tree. A tree topology combines characteristics of linear bus and star topologies. It consists of groups of star-configured workstations connected to a linear bus backbone cable. Tree topologies allow for the expansion of an existing network, and enable schools to configure a network to meet their needs.

1.Point-to-point wiring for individual segments. 2.Supported by several hardware and software venders.

Advantages of a Tree Topology

1. Overall length of each segment is limited by the type of cabling used. 2. If the backbone line breaks, the entire segment goes down. 3. More difficult to configure and wire than other topologies.

Disadvantages of a Tree Topology

HYBRID TOPOLOGYWith the hybrid topology are combination of two or more topologies from a complete Network for example the hybrid topology could be the combination of star and bus topology. If a computer fail. It will not affect the rest of the network.

Physical Topology Common Cable Common Protocol

Linear BusTwisted Pair

CoaxialFiber

EthernetLocal Talk

Star Twisted PairFiber

EthernetLocalTalk

Star-Wired Ring Twisted PairT

Token Ring

TreeTwisted Pair

CoaxialFiber

Ethernet