Network Topologies

Network topology – a way to connect to the same network of network devices, ie Network topology describes the cables and devices, as well as routes that serve to transmit data.

Networks have both physical and logical topology. The term physical topology refers to the physical location of the device and the transmission medium. Typical physical topologies are:

  • bus topology;
  • ring topology;
  • star topology;
  • extended star topology;
  • hierarchical topology;
  • mesh.

<! – {Lofimg src = “/ images / stories / topology.jpg”} ->

Logical topology defines how workstations have access to the transmission medium for sending data.

Bus Topology

Also known as linear bus (linear bus) bus topology (bus topology) involves the connection of all devices in one cable that runs from one computer to another.

Main cable network should end special terminator, which absorbs light, when the latter reaches the end of the line, or electrical signal that represents the data reflected on the end of the cable would cause signal interference and network error.

Star and extended star topology

Star topology (star topology) the most commonly used type of network topology in local area networks and distributed. Star topology consists of a central connection point, which may be a hub, switch or router, and diverging from it cable segment.

Each workstation is connected to the central device of a separate cable, and if you have problems with one of these cable network remains operational as opposed to a bus topology. But at the same time the central point is a major weak spot and a star topology.If the central on-device, the entire network becomes unusable.

Network with a star topology to include additional network devices that are connected to a central point, the resulting topology is called the extended star (extended star topology).

The ring topology

Ring topology (ring topology)-is the topology in which workstations are connected together forming a continuous ring. Method of data transfer over the network is significantly different from that used in the network with bus topology. In this network, a special frame is moved around the ring, stopping at each node. If any node is required to transmit data, it can be inserted into the frame in your details and address. After that, the frame is moved around the ring as long as it reaches the node to the destination address, which retrieves data from that frame. The advantage of this method of data transfer is impossible conflicts .

Hierarchical topology

Hierarchical topology (hierarchical topology) similar to an extended star topology. Only in such a network, there is no central node.Instead, use the main site (trunk node) , which runs the branches (branches) to other nodes. There are two types of hierarchical topology: a binary tree – moving away from each node two compounds, and the backbone tree – the main site has bus-branch, which runs channels to workstations.

Full-and incomplete technology related

In a full mesh network topology (full-mesh topology) all devices (nodes) are connected to each other, which provides redundancy (as a result – the reservation), and fault tolerance. The advantage of this structure is that each node is physically connected to all the others, which provides a high degree of redundancy. If a channel goes down, there are many other routes for you to submit data to the desired destination. The disadvantage is that, with the exception of a very small number of nodes in the network, the number of connections is extremely large. As a result of the implementation of the network becomes extremely costly and difficult to implement. Mesh topology is typically used only in the connection between a router WAN WAN.

Online since incomplete technology related (partial-mesh topology) at least one device supports multiple connections to other devices. Nepolnosvyaznaya topology does cause a certain degree of redundancy due to the presence of several alternative routes.Nepolnosvyaznaya topology used in many telecommunications highways, as well as the global network Internet.

Logical topology networks

Under the logical network topology is understood way of communicating workstations in the network transmission medium. The two main types of logical topology is a broadcast topology and topology that uses token passing.

Using a broadcast topology only means that each workstation on the network environment sends its data to a particular NIC adapter multicast address or a broadcast address. The procedure for transferring data over the network by individual stations is not installed.

According to this principle runs all the Ethernet.

The second type of logical topology is the topology of token passing. Token Passing controls access to the network through the consistent delivery of electronic marker all workstations. When a station receives the token, it can send its data to the network. Two examples of networks that use token passing are the Token Ring and FDDI, which can be regarded as an example of implementation of the technology transfer of the marker on the network with physical ring topology.

Related articles
  • Topology of “star”Topology of “star”
    The network was built on the topology of "star" each workstation connected cable (twisted pair) to the hub or hub (Hub) . Concentrator provides parallel computer and, thus, all the computers connec...
  • Token Ring topologyToken Ring topology
    This topology is based on the topology of the "physical ring connecting a star." In this topology, all workstations are connected to a central hub (Token Ring) in a physical star topology.  Centra...
  • Network Topologies. Bus TopologyNetwork Topologies. Bus Topology
    All computers on the network are connected by lines of communication. Geometric arrangement of lines relative to hosts and physical connection to the network nodes called the physical topology. Dep...
  • All you need to know about the network topologyAll you need to know about the network topology
    Network architecture, including its topology and protocols used, directly affects its performance, including performance and fault tolerance. To estimate the total network performance need to be co...