Computer networks that are not connected by cables are called wireless networks. They generally use radio waves for communication between the network nodes. They allow devices to be connected to the network while roaming around within the network coverage.Types of Wireless NetworksWireless LANs − Connects two or more network devices using wireless distribution techniques.Wireless MANs − Connects two or more wireless LANs spreading over a metropolitan area.Wireless WANs − Connects large areas comprising LANs, MANs and personal networks.Advantages of Wireless NetworksIt provides clutter-free desks due to the absence of wires and cables.It increases the mobility of network devices connected to ... Read More

A wide area network (WAN) is a computer network that covers a large geographical area comprising a region, a country, a continent or even the whole world. WAN includes the technologies to transmit data, image, audio and video information over long distances and among different LANs and MANs.The distinguishing features of WAN areWANs have a large capacity, connecting a large number of computers over a large area, and are inherently scalable.They facilitate the sharing of regional resources.They provide uplinks for connecting LANs and MANs to the Internet.Communication links are provided by public carriers like telephone networks, network providers, cable systems, ... Read More

A metropolitan area network (MAN) is a network with a size greater than LAN but smaller than a WAN. It normally comprises networked interconnections within a city that also offers a connection to the Internet.The distinguishing features of MAN areNetwork size generally ranges from 5 to 50 km. It may be as small as a group of buildings in a campus to as large as covering the whole city.Data rates are moderate to high.In general, a MAN is either owned by a user group or by a network provider who sells service to users, rather than a single organization as ... Read More

A Local Area Network (LAN) is a private network that connects computers and devices within a limited area like a residence, an office, a building or a campus. On a small scale, LANs are used to connect personal computers to printers. However, LANs can also extend to a few kilometers when used by companies, where a large number of computers share a variety of resources like hardware (e.g. printers, scanners, audiovisual devices etc), software (e.g. application programs) and data.The distinguishing features of LAN areNetwork size is limited to a small geographical area, presently to a few kilometers.Data transfer rate is ... Read More

The basic computer hardware components that are needed to set up a network are as follows −Network CablesNetwork cables are the transmission media to transfer data from one device to another. A commonly used network cable is category 5 cable with RJ – 45 connector, as shown in the image below:RoutersA router is a connecting device that transfers data packets between different computer networks. Typically, they are used to connect a PC or an organization’s LAN to a broadband internet connection. They contain RJ-45 ports so that computers and other devices can connect with them using network cables.Repeaters, Hubs, and ... Read More

Computer networks components comprise both physical parts as well as the software required for installing computer networks, both at organizations and at home. The hardware components are the server, client, peer, transmission medium, and connecting devices. The software components are operating system and protocols.The following figure shows a network along with its components −Hardware ComponentsServers −Servers are high-configuration computers that manage the resources of the network. The network operating system is typically installed in the server and so they give user accesses to the network resources. Servers can be of various kinds: file servers, database servers, print servers etc.Clients − ... Read More

Computer networks have become invaluable to organizations as well as individuals. Some of its main uses are as follows −Information and Resource Sharing − Computer networks allow organizations having units which are placed apart from each other, to share information in a very effective manner. Programs and software in any computer can be accessed by other computers linked to the network. It also allows sharing of hardware equipment, like printers and scanners among varied users.Retrieving Remote Information − Through computer networks, users can retrieve remote information on a variety of topics. The information is stored in remote databases to which ... Read More

A computer network is a collection of computing devices that are connected with each other for the purpose of information and resource sharing among a wide variety of users.Each device in the network is called a node which is connected to other nodes through wired or wireless media.The features of a computer network are −Sharing − Computer networks enable sharing of files, software, hardware resources and computing capabilities.Speed: The communication speed among the components is fast enough to be comparable with a centralized system.Scalability − Sizes of computer networks dynamically increase with time. The networks have to be scalable so ... Read More

The function time.time() returns the time in seconds since the epoch, i.e., the point where the time starts.For Unix, the epoch is January 1, 1970. For Windows, the epoch is January 1, 1601.time.time() is used for benchmarking on Windows. time.time() behaves the same on both UNIX and Windows but time.clock() has different meanings.On UNIX, time.clock returns the current processor time expressed in seconds, i.e., the CPU time it takes to execute the current thread so far. While on Windows, it returns the wall-clock time expressed in seconds elapsed since the first call to this function, based on the Win32 function ... Read More