All About Network Topologies
What are Network Topologies?
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| Fig 3.1 : How devices are connected to each other |
- Network topology is the arrangement of the elements (links, nodes, etc.) of a communication network. Network topology is the topological structure of a network and may be depicted physically or logically. It is an application of graph theory wherein communicating devices are modeled as nodes and the connections between the devices are modeled as links or lines between the nodes.
What are Types of Network Topologies?
1. Linear Bus Topology
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| Fig 3.2 : Linear Bus Topology has a backbone, a terminator, and nodes |
- Linear bus topology is a type of network topologyin which each device is connected one after the other in a sequential chain (shown right). In this case, the bus is the network connection between the devices, and if any link in the network chain is severed, all network transmission is halted. It works well for small networks because it is simple to set up and utilizes shorter cables since each device is connected to the next. It is a poor solution for larger networks, however since the entire network relies on each connection, and network speed is reduced as more devices are added.
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| Fig 3.3 : Linear Bus Network Topology |
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| Fig 3.4 : Star Topology connects devices using a hub |
- A Star network is one of the most common computer network topologies. In its simplest form, a star network consists of one central hub which acts as a conduit to transmit messages. In star topology, every host is connected to a central hub. A star network is an implementation of a spoke–hub distribution paradigm in computer networks. The hub and hosts, and the transmission lines between them, form a graph with the topology of a star. Data on a star network passes through the hub before continuing to its destination. The star topology reduces the impact of a transmission line failure by independently connecting each host to the hub. Each host may thus communicate with all others by transmitting to, and receiving from, the hub. The failure of a transmission line linking any host to the hub will result in the isolation of that host from all others, but the rest of the network will be unaffected.
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| Fig 3.5 : Star Network Topology |
3. Ring Topology
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| Fig 3.6 : Ring Topology |
- A ring network is a network topology in which each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node - a ring. Data travels from node to node, with each node along the way handling every packet. Rings can be unidirectional, with all traffic travelling either clockwise or anticlockwise around the ring, or bidirectional. Because a unidirectional ring topology provides only one pathway between any two nodes, unidirectional ring networks may be disrupted by the failure of a single link. A node failure or cable break might isolate every node attached to the ring. In response, some ring networks add a "counter-rotating ring" (C-Ring) to form a redundant topology: in the event of a break, data are wrapped back onto the complementary ring before reaching the end of the cable, maintaining a path to every node along the resulting C-Ring.
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| Fig 3.7 : Ring Network Topology |
4. Mesh Topology
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| Fig 3.8 : Mesh is the best topology to use |
- Mesh network (or simply Meshnet) is a local network topology in which the infrastructure nodes (i.e. bridges, switches and other infrastructure devices) connect directly, dynamically and non-hierarchically to as many other nodes as possible and cooperate with one another to efficiently route data from/to clients. This lack of dependency on one node allows for every node to participate in the relay of information. Mesh networks dynamically self-organize and self-configure, which can reduce installation overhead. The ability to self-configure enables dynamic distribution of workloads, particularly in the event that a few nodes should fail. This in turn contributes to fault-tolerance and reduced maintenance costs. Mesh topology may be contrasted with conventional star/tree local network topologies in which the bridges/switches are directly linked to only a small subset of other bridges/switches, and the links between these infrastructure neighbours are hierarchical.
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| Fig 3.9 : Mesh Network Topology |
5. Hybrid Topology
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| Fig 3.10 : Linear, Star, and Ring Topologies |
- Hybrid topology is an integration of two or more different topologies to form a resultant topology which has many advantages (as well as disadvantages) of' all the constituent basic topologies rather than having characteristics of'
one specific topology. This combination of'topologies is done according to the requirements of' the organization.
Sources : https://en.wikipedia.org/wiki/Network_topology (network topology)https://www.computerhope.com/jargon/l/linear-bus-topology.htm (linear bus topology)https://en.wikipedia.org/wiki/Star_network (star topology)https://en.wikipedia.org/wiki/Ring_network (ring topology)https://en.wikipedia.org/wiki/Mesh_networking (mesh topology)https://blossoms.mit.edu/sites/default/files/video/download/Notes-on-Hybrid-topology.pdf (hybrid)
