Posts Tagged ‘Network Lan’

Connecting Lines: Computer Networking Explained

September 16th, 2009

In a nutshell, computer networking is basically a cluster of computers linked together in a way that it can transmit data and share resources. These sets of connections do not necessitate that the computers bear the same operating systems (OS); it does not even require that similar types of gadgets be used. A perfect example is a personal data assistant (PDA). One may connect a PDA to a laptop over a network. Even kitchen appliances like the internet enabled refrigerator uses networking to activate its surfing functions.

How Is Networking Done?

There are various methods to link computers and other gadgets to a network. And among the plethora of ways and means, the most common networking method is the use of cables. The market provides an assortment of cables from copper-wired to fiber optics each with its advantages and disadvantages.

Copper Wire: Unshielded Twisted Pair Cable (UTP)

The UTP is one of the frequently utilized cables for a local area network (LAN) connection, which is essentially linking a few computers within a small geographical area (thus the name, LAN). Going back to the UTP, this is composed of two unshielded and insulated copper wires coiled and twisted together to diminish electrical interference. This type of cable is often opted due to its flexibility, easy maintenance and low cost. The downside, it can (and will) possibly receive severe blows from electrical interference.

Fiber Optics

Data is exchanged by sending voltages along the wire. But for fiber optics, the data is transmitted through light pulses. While the UTP has copper, fiber optics has threadlike strands of glass, or silica. The process goes like this: the laser translates digital signals into pulses of light and conveys it down the series of glass strands. Fiber optics offer rapid data correspondence, though this speed comes with a price, a pocket burning price. With that said, this kind of connection is often seen being utilized by huge internet service providers (ISP) and data centers, not in office or home networks.

Network Topology: Bus Network

Simply put, network topology is the physical formation of the network. And the bus network is the most straightforward among the various network topologies. Let us begin with the bus. All the machines link up to a linear transmission channel, or the bus.

In operation, when a computer sends off data through the bus, all connected machines can see the data, otherwise known as packet. These packets possess pieces of information tagged as packet headers. And these headers, in turn, reflect the recipient or to which computer or machine the data is intended for. The bus inspects the header: if it is for that computer then the whole packet is recognized and received, but if it is not, it will be merely ignored.

The Downside: One at a Time

Unfortunately, the bus can only handle a single data at any given time. In here, two is a crowd. Imagine what could happen if three computers in the network simultaneously transmit data. Well, you will certainly have a few network problems if this collision happens. Speaking of collision, if and when two computers concurrently send data, the main computer (or the first one that notices the collision) will transmit a blocking sign onto the bus. This will trigger a standstill among the linked computers preventing any further data exchange.

Network Interface Cards (NIC)

NICs usually control the ‘to and fro’ or the transmission of packets across the wires bridging the computers in a single network. It also provides a venue of communication among the computers.

Hub

Hub is intended for small-scale computer networking. The problem with this is that it does not sort packets, meaning the data may be sent to the wrong recipient. Another is that the data will be open for everyone in the network. Security wise, this is not the way to go.

Router

To speed things up, this is a network device that diffuses data packets between two networks bearing different protocols. Yes, it is that blinking box that allows you to connect to the web.

There you go. This is simply scratching the surface of networking. You may opt to scour the internet for more information.




By: Benedict Smythe

Types of Computer Networks – LAN WAN MAN and Area Networks

September 4th, 2009

A computer network is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a mix of computer hardware and computer software. This interconnected system will share services and interact through a communications link.

A computer network is very helpful in a business. Most of the time a business will have more than one computer set up and it often very beneficial to network all of the computers in the office. A local area network (LAN) will connect your company’s computers. This will allow them to share and exchange different types of information. If you haven’t considered networking your office computers, listen to these reasons.

There are several types of computer networks. A computer network can be very simple, such as only connecting two computers or a computer and a printer, or it can be very complex, connecting millions of computers and devices. Here is a list of different computer network types.

The smallest type of network is a Personal Area Network (PAN). This type of computer network connects a computer to a number of devices. These devices may include, but are not limited to, printers, PDAs, and telephones. Usually these are located very close to a computer. A Local Area Network (LAN) is used to network a small geographical area. An example of this type of computer network is a home network with two or more computers or computers that are connected in a workplace. A version of a LAN is a Wireless Local Area Network (WLAN).

A Campus Area Network (CAN) is ideal for a university but they are also found in industrial facilities. This type of computer network connects computers in a number of buildings. This is generally accomplished through bridging and routing. A Metropolitan Area Network (MAN) consists of any number of interconnected LANs and WANs but it will not extend certain boundaries, such as those of a town, city, or metropolitan area. Many of these are operated at public utilities and are used by businesses and individuals in the area.

A Wide Area Network (WAN) is a step up from a MAN. This type of computer network can cross metropolitan or even national boundaries. The best known WAN is the Internet. This computer network uses routers and public communication links to carry data. Many WANs are run by private companies and restricted, unlike the Internet. Although these are the MAN types of network that most users come across there are other computer networks ranging from as small as a Desktop Area Network (DAN) to a very large Global Area Network (GAN).




By: Giri – Austin Whitten

The Home Network How-To Install

August 6th, 2009

With many homes now having more than one computer, home networks are becoming more and more appealing to the average PC user. Networking your computers together allows you to transfer files amongst the different computers at breakneck speeds, as well as share a printer or scanner or other peripheral.

Worldofcables ( Santa Clara) CA – A basic network (LAN or Local Area Network) consists of two computers that are linked in order to share resources (such as printers and CD-ROMs), exchange files, or allow electronic communications.

For this article, we will assume that your local cable or Phone Company has installed a broadband Internet connection on one of your PCs. If they haven’t, then that should be your first step.

Many new homes are being built pre-wired for Internet. This means that you have network cables running throughout your walls and coming out as jacks in the wall in various rooms. If this is the case then you will have an even easier time setting up your network. If not, that’s ok too, as cables can be neatly run under carpets, through attics, or along baseboards.

For the basic network, you will need the following in order to connect two or more computers together (see figure to left):

A broadband internet connection (such as cable modem or DSL)

One CAT-5E network cable for each computer

One CAT-5E network cable for modem

One network interface card for each computer

Note that more and more computers are offering a network card already built in, so check your computer for an Ethernet cable port before purchasing another card. For Cat – 5 E cable visit www.worldofcables.com.

Plan Your Setup

Next, you need to figure out how and where to run the appropriate length cables to fit your specific needs. We offer special flat Ethernet cables specifically designed for running along baseboards and the floor. This helps in keeping them out of the way and from people tripping over them.

Connect one end of a network cable into the back of your DSL/cable modem and the other into the “Internet” port on the back of the router. Connect a network cable in the back of each of your computers and into separate ports in the back of the router. You now have the start of a basic network.

Note that the purpose of the network router is to allow multiple computers to share one internet connection, without having to pay for a multiple-connection option from the internet service provider.

Most new computers will auto-configure your router and get you connected. You may have to configure your computer to turn on DHCP. This allows your router to differentiate between your different computers.

Enable DHCP

If you have a Windows based computer: Go to Start -> Programs -> Control Panel -> Network Connections. Right click on the connection and select Properties. Select Internet Protocol (TCP/IP) and click properties. Select Obtain IP Address Automatically and Obtain DNS Server Address Automatically. If you are using a Windows 2000 machine you must then click Advanced and select DHCP Enabled and click OK. You may have to reboot for the settings to take affect.

If you have a Mac running OS 10.2: Go to System Preferences -> Network. Click on the TCP/IP tab. In the TCP/IP panel, change Configure Manually to Using DHCP. Delete any Domain Name Servers that are listed in the Domain Name Servers box. Click Apply Now.

If you have a Mac running OS 10.3: Go to System Preferences -> Network. From Show, choose Built-in Ethernet. Click on the TCP/IP tab. From Configure, choose Using DHCP. Delete Domain Name Servers. Click Apply Now.

Repeat the above steps for each computer on the network.

Setup Sharing

To allow for the other computers to share certain folders or printers:

If you are running Windows 2000/XP: Right click on any file folder and go to Sharing and Security… Select Share This Folder. Click OK. The other computers on your network can access anything you put in this folder. To share a printer, on the PC with the printer, go to Start -> Printers and Faxes. Right click on the printer you’d like to share and select sharing… Select Share this Printer. Click OK

If you have a Mac running OSX: Go to System Preferences (on the Apple menu) and click on Sharing. Select Personal File Sharing. The “Public” folder in your home folder will now be shared automatically. Use the address displayed at the bottom of the Sharing window to access this folder from other computers. Unlike Windows, Mac OSX does not allow you to share any folder you want. To share printers, select Printer Sharing. For more visit www.worldofcables.com




By: Pradeep Singh