BASIC CONCEPT
 NETWORK ARCHITECTURE
 NETWORK TOPOLOGY

Definition Of Network Topology.

PHYSICAL TOPOLOGY
 LOGICAL TOPOLOGY
  • the configuration of cables,computers and other peripherals. OR
  • the arrangement of a cabling on a network.
  • the path that data travels between computers on a network. OR
  • how signal travels along the physical path.
**Node - any device that is connected to a network.


 Bus
 Ring
 Star
Diagram






Definition/Physical topology
  • A bus network consists of a single cable (backbone/trunk),to which all computers and other devices connect (node).
  • A cable forms a closed loop (ring) with all computers and devices arranged along the ring.
  • All the computers and other devices on the network connect to a central device (hub/switch), thus forming a star.
Advantages
  • Failure of one device usually does not affect the rest of the bus network.
  • Bus network are inexpensive and easy to install.
  • Computers and other devices can be attached and detached at any point on the bus without disturbing the rest of the network.
  • All computers have equals access to the resources in the network.
  • The uses of token passing enable all devices in a ring topology to share the network resources fairly.
  • Cable faults are easily located,making troubleshooting easier.
  • Data packeting are flowing in one direction at high speed around the ring.
  • The transmission of data is relatively simple as packets travel in one direction only.
  • If one device (pc/printer) fails,only that device is affected.
  • Devices (pc/printer) can be added to or removed from network with little or no disruption.
  • Easy to troubleshhot and isolate problem.
Disadvantages
  • The network will be mulfunctioned if the single central cable breaks down.
  • A break in the backbone (single central cable) will prevent all system from accessing the network.
  • If mote computers are connected,the performance of the netwrok will become slower because of data collision.
  • It is difficlut to identify the problem if the entire network shut down.
  • The network will be mulfunctioned if the device (pc/printer) breaks down.
  • A ring network can span a larger distance than a bus network,but it is more diffiicult to install.
  • Data packets must pass through every computer therefore,this makes it slower.
  • The network will bbe mulfunctioned if the hub or switch break down.
  • Requires more  cable than most of the other topologies.