Circuit Switching
Circuit switching dominates the public switched telephone network or PSTN. Network resources set up calls over the most efficient route. That might mean a call from New York to San Francisco goes through switching centers in San Diego, Chicago, and Saint Louis. But no matter how convoluted the route, that path or circuit stays the same throughout the call. Got it? One call, one circuit. It's like having a dedicated railroad track with only one train, your call, permitted on the track at a time.
Packet Switching
Packet switching dominates data networks like the internet. A data call or communication from San Francisco to New York is handled much differently than with circuit switching. With circuit, all packets go directly to the receiver in an orderly fashion, one after another on a single track. Like the train we mentioned before, hauling one boxcar after another. With packet switching routers determine a path for each packet or boxcar on the fly, dynamically, ordering them about to use any railroad track available to get to the destination. Other packets from other calls race upon these circuits as well, making the most use of each track or path, quite unlike the circuit switched calls that occupy a single path to the exclusion of all others.
LAN
A local area network (LAN) is a group of interconnected computers that share the same geographic location, such as an office. This is opposed to a wide area network (WAN), which connects computers over greater distances, and would be used to link branch offices.
Each computer connected to a LAN is able to access the other connected computers' hard drives, as if they were installed internally. Also, you can connect your LAN to a file server, which is specifically designed to house shared files and resources for all the networked computers to access.
WAN
A WAN is a data communications network that covers a relatively broad geographic area and often uses transmission facilities provided by common carriers, such as telephone companies. WAN technologies function at the lower three layers of the OSI reference model: the physical layer, the data link layer, and the network layer.
A point-to-point link provides a single, pre-established WAN communications path from the customer premises through a carrier network, such as a telephone company, to a remote network. A point-to-point link is also known as a leased line because its established path is permanent and fixed for each remote network reached through the carrier facilities.
In conclusion, a local area network is made up of computers and a myriad of devices, such as routers, servers, switches, and firewalls. In order for it to connect to the Internet, a router must be installed. Servers provide special functions such as printing, file sharing, etc. Switches connect the computers together from different parts of the network. Firewalls prevent unauthorized access. There are a host of other devices that may be used as well. These devices are hubs, gateways, repeaters, wireless access points,
Meanwhile, the advent of early PC’s and the recognition of the value in networking devices together gave rise to Local Area Networks. These LAN’s were developed from a business customer perspective, which placed more emphasis on costs and ease of use over reliability. There were a number of different competing LAN technologies, two of the most common being Token Ring (IBM) and Ethernet (everyone else). The triumph of Ethernet in the marketplace, to the extent where it is included in every PC, game console and some refrigerators, provides a consistent and relatively inexpensive way to build internal networks with relative ease.
A network switch is a small hardware device that joins multiple computers together within one LAN.
... access to what and in which sequence. The router connects the LAN to other networks, which could be the Internet or another corporate network so that the LAN can exchange information with networks external to it. The most common LAN operating systems are Windows, Linux, and Novell. Each of these network operating systems supports TCP/IP as their default networking protocol. Ethernet is the dominant LAN standard at the physical network level, specifying the physical medium to carry signals between computers, access control rules, and a standardized set of bits used to carry data over the system. Originally, Ethernet supported a data transfer rate of 10 megabits per second (Mbps). Newer versions, such as Fast Ethernet and Gigabit Ethernet, support data transfer rates of 100 Mbps and 1 gigabits per second (Gbps), respectively, and are used in network backbones.
In an organization, systems are deployed and configured in the LAN – Local area network. The LAN is the private network of the organization. The public network refers to the internet. Devices on the private network are not directly connected to the public network. The organization would use devices like routers, firewalls to provide public network access to the private network users.
Institute, C. L. (2005). Switching and Routing. In R. H. Ivy, Networking + Fundamentals and Certification (pp. 192-193). Upper Saddle River, NJ: Prentice Hall.
In this modern times a revolution is taking place. Quietly this revolution has started and grown that it involved the world. A revolution is a sudden change in the way people live (Merriam-Webster). The birth of computer networking started during the early 1970's and began to flourish during the late 1970's. Various manufacturers in the computer industry launched small minicomputers with enough computational power to cater the needs of several users. Because of the cheap prices of such computers, every department in sizable organizations can afford one. In order to interconnect minicomputers and allow swift transfer of information among them, a number of organizations started to install Local Area Networks. Because LAN Technology is both cheap and easy to install, an individual department can buy, install and operate a LAN for their minicomputers without seeking the help of the administration (Comer, 2007)
In comparison to circuit switching, packet switching has some pros and cons over circuit switching.
Local Area Networks also called LANs have been a major player in industrialization of computers. In the past 20 or so years the worlds industry has be invaded with new computer technology. It has made such an impact on the way we do business that it has become essential with an ever-growing need for improvement. LANs give an employer the ability to share information between computers with a simple relatively inexpensive system of network cards and software. It also lets the user or users share hardware such as Printers and scanners. The speed of access between the computers is lighting fast because the data has a short distance to cover. In most cases a LAN only occupies one or a group of buildings located next to each other. For larger area need there are several other types of networks such as the Internet.
One of the most basic types of topologies is Point to Point, where a connection between two nodes is established just to communicate between the two. One of most basic examples of this is a two tin can’s on a string; they are connected to each other just so the two can communicate. This relationship can also be observed with two computers connected with a crossover Ethernet cord. This method of connection is also used for communication through telephone, but this is achieved logically. Switched telecommunications systems are used to create a link between two phones to connect them and allow communications between the two and then dropped when the connection is no longer needed. Point to Point communication in modern times is still prevalent, but achieved using more complex networks with the help of logical networking, and can be used to describe many of the connections between individual parts of a network.
It is a network of limited devices connected with each other. It is a private network, in which computers communicate with each other which are within the same network. No outside device can communicate with devices connected in intranet.
programs used to link two or more computers. Network users are able to share files,
lines and radio waves; this is what we call a WAN (a system of LANs
Before we begin our discussion on transporting voice over a data networks, it is important to understand the concept and terms associated with a traditional telephone network. One of the most common piece of telecommunication equipment used today is the telephone. When you plug an ordinary analog telephone into the wall jack installed by the local telephone company, you are connected to the telephone network and are able to place calls. 1), but how is this process performed?
This report will describe the two forms of data communications in terms of the physical interfaces and modes of operation. It will describe the features of data communications equipment in relation to synchronous and asynchronous communication including modems, network terminating units and sending and receiving equipment.