NETWORK TOPOLOGY

Network Topology

Introduction

Network topology

All computers on the network are connected by communication lines. Geometric arrangement of lines with respect to network nodes and the physical connection to the network node is called the physical topology. Depending on the topology of the network are distinguished: bus, ring, star, hierarchy, and arbitrary structure.

Distinguish between physical and logical topology. The logical and physical network topology is independent of each other. Physical topology - is the geometry of building a network, and logical topology defines the direction of data flow between network nodes and data options.

Currently, local networks, the following physical topologies: physical "bus" (bus);

Physical "star" (star)

Physical "Ring" (ring)

(Token Ring) physical star and logical ring "(Token Ring)”

Discussion

Discuss the benefits and constraints of different networking system types of topologies

Following are the different networking system types of topologies with there benefits and constraint.

Bus topology

Network with bus topology using mono line (coaxial cable) data at the ends, of which are set terminal resistor (terminator), every computer connected to the coaxial cable using a T-connector (T - connector). The data from the transmitting node are transmitted on the bus both ways, reflecting from the end-terminators. Terminators prevent reflected signal, used to suppress signals that reach the ends of the data channel. Thus, the information goes to all the nodes, but only accepted by the node to which it is intended. In a logical bus topology, transmission media are used jointly and simultaneously by all PCs on your network, and signals from the PC are released simultaneously in all directions on the transmission medium. Since the transmission of signals in the physical bus topology is a broadcast, signals are released simultaneously in all directions, and then the logical topology of a given network is a logical bus.

This topology is used in local area networks with the architecture of Ethernet (10Base-classes 5 and 10Base-2 for the thick and thin coaxial cable, respectively).

The benefits of a bus topology networks:

Failure of one node does not affect the network as a whole

Network is easy to set up and configure

Network is resistant to faults separate units

Constraint of network bus topology:

Break the cable can affect the entire network

Limited cable length and number of workstations

Difficult to identify defects in the compounds

The topology of a star

In a network constructed by the topology of a star every workstation connected cable (twisted pair) to a hub or a hub (hub). Concentrator provides a parallel connection of a PC and, thus, all computers connected to the network can communicate with each other.

The data from the transmitting station are transmitted through a network hub for all communication lines to all PCs. Information delivered to all workstations, but received only by those stations, which it is intended. Since the transmission of signals in a physical star topology is broadcast, signals from the PC are released simultaneously in all directions, and then the logical topology of the network is a logical bus. This topology is used in local area networks with the architecture of 10Base-T ...