The way in which network is designed depends specifically on what the network will be used for. The unique interconnection between devices which enable the way they are able to communicate is known as a topology. There are several topology networks. A topology is taking of the elements needed to create a network and arranging them effectively for that network to operate as desired.
A network topology is the configuration of computers with an interconnection consisting of two types of topologies; physical, and logical. The topologies are arranged or mapped to form a network. Each topology plays a part in the interconnection process. A physical topology is responsible for the physical mapping of computers. It is representative of the physical structure of a network, its devices, location and installation of the cable (Satalkar, 2010). A logical topology is responsible for mapping the transference of the data paths of a network. There are several types of physical topologies which are bus, ring, mesh, star, and tree and each has its own discriminate interconnection process. (Satalkar, 2010)
The bus topology network consists of computers connected to a common transmission, which serves as a medium with two endpoints. The bus is the foundation of this network, wherein the data travels and is transmitted. This type of network is also referred to as a “linear bus topology”, because of the medium, having two endpoints. If the medium had more than two endpoints, it would be referred to as having a “distributed bus topology” (Oak, 2011). A bus topology network is typically more effective when used with small networks. This is because the cable length is limited, and this, in turn, limits connection strength and can result in a decreased computer response. It is still an extensive network due to the ease in which it can be installed, and it is easy to use (Oak, 2011).
An advantage of a bus topology is that it is easy to maintain and handle. A disadvantage of a bus topology is its cable limitations which restrict the number of connections that can be made to other computers. The ring topology network works by connecting computers to create a uniform operation system within the network. To clarify, each computer is connected to two more computers and ends by connecting the first computer to the last computer, which completes the ring pattern. Each computer in the network takes its turn at communicating in the circle formation with data being transmitted in one direction, which could be sent in going forward or reverse and passing through computers as signals until they reach their destination. If the data is needed to travel in more than one direction, then dual connections are created among computers (Oak, 2011).
An advantage of a ring topology is that a master computer is not needed for effective transmissions. The disadvantage of a ring topology is that with this type of network, if changes are made, or if it is moved, this may cause a station to fail. If one station fails, the network will cease to operate.
A mesh topology network can be either partially connected or fully connected. The connectivity of this network is established by connecting every other node. A fully connected mesh topology network setup is arranged in a manner that creates flexibility within the transmission signal. It enables a signal to be received by one computer that instantly spreads to other computers. This network is preferred for its consistently short transmissions that do not require the use of all of the computers, as with this network only some of the network computers are connected to more than one computer (Oak, 2011). For this network to be effective, the computers require routing that provides the shortest route to accommodate sending and receiving of the signals and data during transmissions.
An advantage of a mesh topology is its capability to transfer data from one computer to another simultaneously. A disadvantage of a mesh topology is that many connections are not used which results in a redundancy of those which are;
A Star topology network requires the connection of all computers in the network to a hub. A hub is simply the main or the master computer. The way this works is that all data from the other computers is transmitted through the master computer. This network gets its name by the unique pattern of its connections “A distributed star formed by the interconnection of two or more individual star networks” (Oak, 2011). The use of a master computer assists in supporting and allowing the isolation of data for the individual computers, however, the transmissions rest solely on the master computer for effectiveness. If the master computer experiences any issues, the entire network will be compromised (Alphonse, 2011). Advantages of a star topology is that it is quite easy to install and require minimal wiring. Because it is centralized, it is easier to maintain. Plus, the removal of devices will not cause any disruption to the network. Disadvantages of a star topology are that it requires more cable length than a bus topology. Due to the necessity of being centralized, it renders the entire network as vulnerable on its dependency on the master computer. If the master computer fails, the entire network will become inoperable.
A Tree topology network setup combines both that of bus and star topologies. It is a system that rises like a tree by integration of multiple star networks and their master computers to a bus topology. In clarification, “it allows for multiple hubs to exist on a network which act as roots for terminals connected to them” (Phatak, 2011).
An advantage of a tree topology is that it is a excellent choice when a large network is needed. Its structure accommodates by dividing the entire network into easily managed sections. Because it is supported by some hardware and software vendors, this makes parts easier to get. A disadvantage of a tree topology is that it is harder to configure it, and it requires more wiring than other networks, and as the size of the network increasing the ability to manage, it will become more difficult.
All of these topologies make up the routine basis of networking. There are also “hybrid network topologies”. These consist of combining two or more topologies. For example, bus, ring, mesh, star, tree, for added support and resiliency, with the aim of getting the most advantage out of these networks.
Some things that should be considered when building a network topology is the cost. One would better choose the network that matches the needs it is required for the most. This will help to balance the amount of maintenance and money that must be invested into it. The star topology is the most expensive, while a bus topology is the least expensive. Other considerations are the cable length, which expands with bigger networks, and decreases with smaller networks in meeting the specific needs of the desired network. The type of cable to be used is also important. Also, the future growth potential of a network should be considered. This would be in alignment with a star topology, as it is hierarchical, but keeps in mind the larger it grows, the harder it is to manage.
In conclusion, Roy Winkelman (2011) advises an easy way to remember the basic foundations of the physical topology networks, which is that a linear bus topology protocol is Ethernet, and uses a twisted pair coaxial fiber cable.