Network topology refers to the layout or structure of the network in relation with the flow of data. Can be used to define or describe the arrangement of various types of telecommunication network, including command and control radio networks, industrial field busses and computer networks. It is a substantial arrangement of a network in which all nodes are connected with each other using network link or connecting lines. Apart from just describing how he nodes are interconnected, network topology also explains how the data is transferred in a network. And may be depicted physically or logically.
Howard Frank had founded Network Analysis Corporation (NAC), a company specializing in topological design based on hid groundbreaking work at the Office of Emergency Preparedness (OEP). Frank remembers Robert's call requesting a meeting: Arpanet was a four node network
Physical Topology refers to the interconnected structure structure of a local area network (LAN). The method employed to connect the physical devices on the network with the cables, and the type of cabling used, all constitute the physical topology.
Logical Topology is a concept in networking that defines the architecture of communication mechanism for all nodes in a network. Using network equipment such as routes and switches, the logical topology of a network can be dynamically maintained and reconfigured.
Types of Network Topologies:
Linear Bus Topology
Linear bus topology is a type of network topology where each device connects one after the other in a sequential chain (shown right). In this case, the bus is the network connection between the devices. It uses a long cable, referred to as a backbone, to which computers and other devices attached. If any link in the network chain is severed, all transmission is halted.
Advantages of Linear Bus Topology:
👍 It is the easiest network topology for connecting peripherals or computer in a linear fashion.
👍 It works very efficient well when there is a small network.
👍 It requires less cable length than the star topology.
👍 It is easy to connect or remove devices in this network without affecting any other devices.
👍 Very cost-effective as compared to the other network topology i.e. mesh and star
Disadvantages of Linear Bus Topology:
👎 Bus topology is not great for large network.
👎 Identification of problem becomes difficult if whole network goes down.
👎 The entire network shuts down if there is a break in the backbone.
👎 Need of terminators are required at both ends of main cable.
👎 This network topology is very slow as compared to other topologies.
Bus topology is one of the simplest physical topology used for the network. This topology is famously used for Local Area Network. Small workgroup whose computers are connected using thinnest cable. Trunk cables connecting hubs or switches of department LANs to form a larger LAN.
Star Topology
Star topology is one of the most common network setups. In this configuration, every node connects to a central network device, like a hub, switch, or computer. The central network device acts as a server and the peripheral devices acts as clients. Data from the computer passes through the hub or switch before it can reach the other target node.
Advantages of Star Topology:
👍 Easy to install and wire.
👍 No disruptions to the network when connecting or removing devices
👍 Easy to detect faults and to remove parts.
👍 Centralize management of the network, through the use of central computer, hub, or switch.
👍 It provides very high speed data transfer.
Disadvantages of Star Topology:
👎 Entire performance of the network depends on the single device hub.
👎 If the hub device goes down, the entire network will be dead.
👎 Requires more wires compared to the ring and bus topology.
👎 Purchasing the network cabling and file servers can be expensive.
👎 Viruses can spread to other computers throughout a computer network.
Stark network topologies are common in home networks, where the central connection point may be a router, switch or networking hub. Unshielded Twisted Pair (UTP) Ethernet cabling is typically used to connected devices to the hub, though coaxial cable or optical fiber may also be employed.
Ring Topology
Ring topology is a network configuration where device
connections create circular data path. Wherein nodes are connected to each other forming one contiguous pathway in a ring formation. In other words, data need to travel from one node to the next, with each one receiving data traffic and passing it along to the next until it reaches its final destination.
connections create circular data path. Wherein nodes are connected to each other forming one contiguous pathway in a ring formation. In other words, data need to travel from one node to the next, with each one receiving data traffic and passing it along to the next until it reaches its final destination.
Advantages of Ring Topology:
👍 All data flows in one direction, reducing the packet chance of packet collisions.
👍 Each repeater duplicates the data signals so that there is a very little signal degradation.
👍 A network server is not needed to control network connectivity between each workstation.
👍 Data can transfer between workstations at high speed.
👍 Additional workstations can be added without impacting performance of the network.
Disadvantages of Ring Topology:
👎 All data being transferred over the network must pass through each workstation on the network, which can make it slower than a star topology.
👎 The entire network will be impacted if one workstation shuts down.
👎 It is expensive.
👎 Difficult to troubleshoot the ring.
👎 Addition and removal of any node during a network is difficult and may cause issue in network activity.
Ring topology are most often found on school campuses, though some commercial organizations also use them. FDDI, SONET, or Token Ring technology are typically used. In Wide Area Networks (WAN) and Metropolitan Area Networks (MAN), a ring topology is used to as the topology for the backbone connect the costumers.
Mesh Topology
Mesh topology is a network setup where each computer and network device is interconnected with another. This network are structures wherein all the nodes on the network can route data traffic on their one. This topology setup allows for most transmission to be distributed even if one of the connections goes down. Has multiple connections, making it the most fault tolerant topology available.
Advantages of Mesh Topology:
👍 Manages high amounts of traffic, because multiple devices can transmit data simultaneously.
👍 A failure of one device does not cause a break in the network or transmission of data.
👍 Adding additional devices dost not disrupt data transmission between other devices.
👍 Fault identification is easy because of point to point connection.
👍 It provides high privacy and security.
Disadvantages of Mesh Topology:
👎 Requires high NO: of cables and I/o ports for communication.
👎 Installation is very difficult in mesh topology, as each node is connected to every node.
👎 Mesh topology is costly compared to other network topologies
👎 The chance of redundant connections is high, which adds to the high costs and potential for reduced efficiency.
👎 Building and maintaining the topology is difficult and time consuming
Mesh topology is a type of networking where all nodes cooperate to distribute data amongst each other. This topology was originally develop 30+ years ago for military applications, but today, they are typically used for things like home automation, smart HVAC control, and smart buildings.
Hybrid Topology
Hybrid topology is a type network topology that uses two or
more differing network topologies in such way the final network does not exhibit one of the characteristics of the standard topologies. This combination of topologies is done according to the requirements of the organization. Good examples of a hybrid network are star-ring and star-bus network.
Advantages of Hybrid Topology:
👍 Hybrid network combines he benefits of different types of topologies.
👍 Can modified as per requirement.
👍 It is extremely flexible.
👍 It is very reliable.
👍 It is easily scalable.
Disadvantages of Hybrid Topology:
👎 The design of a hybrid network is complex.
👎 It is expensive.
👎 Hardware changes are required in order to connect topology to another topology.
👎 Installation is a difficult process.
👎 Hubs which are use to connect two distinct network, are very costly. And hubs are different from usual hubs as they need to be intelligent enough to work with different architectures.
If there is a Mesh topology in one office department while a Ring topology is another department, connecting these two with bus topology will result in Hybrid topology. The choice to use hybrid topology over a standard topology depends on the need of a business, school, or the users.







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