The paper “ Applied Data Communications and Networks by Buchanan” is a great example book review on information technology. A computer network is the connection of a group of computers together with the motive of data and information sharing. Computer network topology, therefore, is the manner in which individual computers connect, including the devices and the nodes used. There are three common types of network topologies which include; the fully connected or mesh, bus, star and hub topologies. The mesh topology allows the interconnection of the computer and other devices with each other.
Every node is therefore capable of sending its own signal as well as disseminating data from other nodes. It is the most difficult to build and the number of connection at each node equals the total number of nodes minus one. Bus networks are characterised by competition for possession by all nodes on a common bus. Data is transmitted when an idle bus is detected. A collision occurs when two or more nodes transmit data simultaneously, and this is handled by the Carrier Sense Multiple Access with Collision Detection, which causes nodes to stop and wait before data retransmission. Instar networks, all the nodes connect to a central communication hub known as the concentrator.
Small networks require only a single hub with4, 8, 16, 32 or more connections available. Large networks require multiple hubs thus increasing hardware and cabling costs. Fig 1.1: Topologies for a five node network In-ring networks, each node is connected to two other nodes and the data circulates in a ring. It consumes time since information travels around a ring and link failure can cause network failure.
Network access points offer access to national, as well as global network traffic. Companies can install communication networks by connecting to one or more NAPs or acting as NAPs themselves. NAP connected companies enter into agreements which allow traffic exchange. Chapter 3: Networking HardwareThe basic networking hardware components comprise of cabling, network interface cards, repeaters, transceivers, hubs, switches, router and firewalls. The major cable types that are used are the Ethernet cables and the specialised cables. Ethernet cables enhance fast connections between two devices like computers and routers. The three main varieties of Ethernet cables are the RG-58 coaxial cables or thin wire such as the 10 bases 2 operations, the RG-11 coaxial cable or thick wire such as the 10 bases 5 operations and the unshielded twisted pair (UTP) which comprises of 10 base T, 100 base T and 1000 base T operations. The UTP cable is used with hubs switches and other 10 or 100 base T equipment.
The twisted pair wires are advantageous because they reduce noise and cross talk and allow higher speed data rates. Fibre optic cables, on the other hand, use light pulses in the transmission of information down the fibre lines.
The construction of these cables requires plastic or glass with different properties. The light beam used reflects off the boundary between the core and the cladding. The expression of the fibre optic sizes is usually given in terms of the core size followed by the cladding size. There are two major classes of the fibre optics cables.
ReferencesBuchanan, W. (2012). Applied Data Communications and Networks. Boston, MA: Springer US.