Topology
The term “Topology” refers to the way in which the end points or stations/computer systems, attached to the networks, are interconnected. We have seen that a topology is essentially a stable geometric arrangement of computers in a network. If you want to select a topology for doing networking. You have attention to the following points.
(1) Mesh topology.
(2) Star topology.
(3) Tree (Hierarchical) topology.
(4) Bus topology.
(5) Ring topology.
(6) Cellular topology.
- Application S/W and protocols.
- Types of data communicating devices.
- Geographic scope of the network.
- Cost.
- Reliability.
(1) Mesh topology.
(2) Star topology.
(3) Tree (Hierarchical) topology.
(4) Bus topology.
(5) Ring topology.
(6) Cellular topology.
- Ring and mesh topologies are felt convenient for peer to peer transmission.
- Star and tree are more convenient for client server.
- Bus topology is equally convenient for either of them.
Mesh Topology
The value of fully meshed networks is proportional to the exponent of the number of subscribers, assuming that communicating groups of any two endpoints, up to and including all the endpoints, is approximated by Reed's Law.
The number of connections in a full mesh = n(n - 1) / 2
The number of connections in a full mesh = n(n - 1) / 2
Star Topology
In a star topology, cables run from every computer to a centrally located device called a HUB. Star topology networks require a central point of connection between media segment. These central points are referred to as Hubs.
Hubs are special repeaters that overcome the electromechanical limitations of a media. Each computer on a star network communicates with a central hub that resends the message either to all the computers. (In a broadcast network) or only the destination
computer. (In a switched network).
Ethernet 10 base T is a popular network based on the star topology.
Hubs are special repeaters that overcome the electromechanical limitations of a media. Each computer on a star network communicates with a central hub that resends the message either to all the computers. (In a broadcast network) or only the destination
computer. (In a switched network).
Ethernet 10 base T is a popular network based on the star topology.
Tree (Hierarchical) topology
It is similar to the star network, but the nodes are connected to the secondary hub that in turn is connected to the central hub.
The central hub is the active hub.
The active hub contains the repeater, which regenerates the bits pattern it receives before sending them out.
The secondary hub can be either active or passive.
A passive hub provides a simple physical connection between the attached devices.
The central hub is the active hub.
The active hub contains the repeater, which regenerates the bits pattern it receives before sending them out.
The secondary hub can be either active or passive.
A passive hub provides a simple physical connection between the attached devices.
Bus topology
A bus topology connects computers along a single or more cable to connect linearly. A network that uses a bus topology is referred to as a "bus network" which was the original form of Ethernet networks. Ethernet 10Base2 (also known as thinnet) is used for bus topology.
Ring topology
In ring topology, each device has a dedicated point-to-point line configuration only with two devices on either side of it.
A signal is passed along the ring in one direction, from device to device until it reaches its destination.
Each device in the ring has a repeater. When the devices receive the signal intended for the other node, it just regenerates the bits and passes them along.
Ring network passes a token.
A token is a short message with the electronic address of the receiver.
Each network interface card is given a unique electronic address, which is used to identify the computer on the network.
A signal is passed along the ring in one direction, from device to device until it reaches its destination.
Each device in the ring has a repeater. When the devices receive the signal intended for the other node, it just regenerates the bits and passes them along.
Ring network passes a token.
A token is a short message with the electronic address of the receiver.
Each network interface card is given a unique electronic address, which is used to identify the computer on the network.
Cellular topology
The cellular topology is applicable only in case of wireless media that does not require cable connection.
In wireless media, each point transmits in a certain geographical area called a cell.
Each cell represents a portion of the total network area.
Devices that are in the cell communicate through a central hub. Hubs in different cells are interconnected. They route data across the network and provide a complete network infrastructure.
The data is transmitted in the cellular digital packet data (CDPD) format.
In wireless media, each point transmits in a certain geographical area called a cell.
Each cell represents a portion of the total network area.
Devices that are in the cell communicate through a central hub. Hubs in different cells are interconnected. They route data across the network and provide a complete network infrastructure.
The data is transmitted in the cellular digital packet data (CDPD) format.
