Edison_ilustre,Rea+Asella+D.+-Assignment+no.1

what is network? -A computer network, often simply referred to as a network, is a collection of computers and devices interconnected by communications channels that facilitate communications among users and allows users to share resources. Networks may be classified according to a wide variety of characteristics. A computer network allows sharing of resources and information among interconnected devices. A network is a group of two or more computer systems linked together. There are many types of computer networks, including: local-area networks (LANs) : The computers are geographically close together (that is, in the same building). wide-area networks (WANs) : The computers are farther apart and are connected by telephone lines or radio waves. campus-area networks (CANs): The computers are within a limited geographic area, such as a campus or military base. metropolitan-area networks MANs): A data network designed for a town or city. home-area networks (HANs): A network contained within a user's home that connects a person's digital devices. In addition to these types, the following characteristics are also used to categorize different types of networks: topology : The geometric arrangement of a computer system. Common topologies include a bus, star, and ring. See the Network topology diagrams in the Quick Reference section of Webopedia. protocol : The protocol defines a common set of rules and signals that computers on the network use to communicate. One of the most popular protocols for LANs is called Ethernet. Another popular LAN protocol for PCs is the IBM token-ring network . architecture : Networks can be broadly classified as using either a peer-to-peer or client/server architecture. Computers on a network are sometimes called nodes. Computers and devices that allocate resources for a network are called servers. (v.) To connect two or more computers together with the ability to communicate with each other. WHAT IS TOPOLOGY? -Network topology is the layout pattern of interconnections of the various elements (links, nodes, etc.) of a computer network.Network topologies may be physical or logical. Physical topology means the physical design of a network including the devices, location and cable installation. Logical topology refers to how data is actually transferred in a network as opposed to its physical design. Topology can be considered as a virtual shape or structure of a network. This shape does not correspond to the actual physical design of the devices on the computer network. The computers on a home network can be arranged in a circle but it does not necessarily mean that it represents a ring topology. Any particular network topology is determined only by the graphical mapping of the configuration of physical and/or logical connections between nodes. The study of network topology uses graph theory. Distances between nodes, physical interconnections, transmission rates, and/or signal types may differ in two networks and yet their topologies may be identical. A local area network (LAN) is one example of a network that exhibits both a physical topology and a logical topology. Any given node in the LAN has one or more links to one or more nodes in the network and the mapping of these links and nodes in a graph results in a geometric shape that may be used to describe the physical topology of the network. Likewise, the mapping of the data flow between the nodes in the network determines the logical topology of the network. The physical and logical topologies may or may not be identical in any particular network. DIFFERENT TYPES OF NETWORK TOPOLOGY -Point-to-point topology Bus (point-to-multipoint) topology Star topology Ring topology Tree topology Mesh topology Hybrid topology This classification is based on the interconnection between computers — be it physical or logical. The physical topology of a network is determined by the capabilities of the network access devices and media, the level of control or fault tolerance desired, and the cost associated with cabling or telecommunications circuits. Networks can be classified according to their physical span as follows: LANs (Local Area Networks) Building or campus internetworks Wide area internetworks

