Computer network is an integral part of our daily lives, with the most important reason being that of communication. The use of computer networking is to share resources like fax machines, printers, modems, files etc., and its other uses are database server, computer server, email, chat, internet etc. The computer to which the resources are attached is called the server and the other computers that access the resource are called clients. In peer-to-peer computer networks there are no servers.

The sharing of fax machines, printers, and modems amongst many computers and users reduce the operational cost. A database on a computer network is a very important application as it stores and runs many important data and jobs. Emails and chats can be used for instantaneous communication and sending of files on a computer network.

The computer networks are classified, depending upon the size, as Local Area Networks (LAN), Wide Area Networks (WAN), Metropolitan Area Networks (MAN) and Personal Area Networks (PAN). The topology (topology is the way the computer networks and network resources are connected) of the networking can be classified as Bus Network, Ring Network and Star Network.

The networking hardware basically consists of wiring, network cards and a hub. Computer network cards are required so that one computer can understand what the other computer is “talking”. Network cards have a unique MAC address to identify computers on a computer network. Hubs connect all the computers in the network. Hubs can also be used to connect to other hubs to increase the size of the computer network. Two computers can be connected using Ethernet cards or phone lines or power lines for communication, with hardware kits available at roughly a cost of $100.

As the number of computers in an office or a home increases, so do the number of cables, so wireless networking is a viable solution. In wireless networking radio transreceivers or infrared signals are used to communicate between computers and devices. Examples of wireless networking include Wi-fi and Bluetooth technology, though there may be security issues involved in wireless networking. However there definitely is a stronger preference towards wireless networking nowadays among consumers.

Computer networks have added a new dimension to the 21st century. Today the cyber world is much faster and wider than the real world. This has all been made possible due to computer networks. Computer networks have revolutionized business, communication, travel, research, defense, society and almost all human endeavors. The evolution of computer networks has helped the technological revolution take a big leap forward.

What’s my IP and what do its numbers stand for?
IP stands for Internet Protocol and the address is formed from 4 numbers separated by periods. The IP address format is a 32 bit numeric one and each number can be from 0 to 255. The IP address consists of two parts: first one represent the network number and it is similar for more than one user (like the number of a street) and second represents the host name which is different for each user (like the house number). To increase the number of available IP addresses within big networks with a lot of users or small networks with few hosts, the address is divided into 4 classes (A, B, C, and D)

Having an IP address it’s like having a last name in a network. To identify a computer in a network (LAN-local area network, WAN-wide area network or on the Internet) it has to have an IP address. This number is similar to a phone number or to a zip code. It is unique and without it the device or computer can not be used in a network area. Within an isolated network the computers can be assigned different random IP addresses, but if a private network needs to be connected to the Internet the IP has to be registered so that its uniqueness is verified.

Where do I find my IP address?
Connect to a site that recognizes your IP address and let you see it also. You can visit this site for example: iprelated.com. These IP Lookup sites are very easy to use and very useful for others. An IP address can offer a lot information about the person who logs in on the Internet and engages in a certain activity.
This is how illegal activity is sometimes detected and violations are reported. The IP address says less about the user if it is a dynamic one because it changes every time the user logs in.
Another interesting aspect is that some people who have the information from your IP address are interested in taking you computer over and using its resources. This is not impossible! They can use software that enables them to do this so it is better to hide your IP when you are online.

Who gives me my IP address?
The IP address can be static or dynamic, meaning it can be the same every time you are online or it can change. The IP address is provided by a server through a service called DHCP (Dynamic Host Configuration Protocol)

Although things can get pretty complicated when explaining numbers and their significance, this is just a small and easy to understand introduction about the IP address that does not involve technical terms. The importance of these details is very high because starting from these brief explanations one can truly comprehend the necessity and implications of the IP address and of virtual geo location.

Every network that has an internet connection is at risk of being compromised. Whilst there are several steps that you can take to secure your LAN, the only real solution is to close your LAN to incoming traffic, and restrict outgoing traffic.

However some services such as web or FTP servers require incoming connections. If you require these services you will need to consider whether it is essential that these servers are part of the LAN, or whether they can be placed in a physically separate network known as a DMZ (or demilitarised zone if you prefer its proper name). Ideally all servers in the DMZ will be stand alone servers, with unique logons and passwords for each server. If you require a backup server for machines within the DMZ then you should acquire a dedicated machine and keep the backup solution separate from the LAN backup solution.

The DMZ will come directly off the firewall, which means that there are two routes in and out of the DMZ, traffic to and from the internet, and traffic to and from the LAN. Traffic between the DMZ and your LAN would be treated totally separately to traffic between your DMZ and the Internet. Incoming traffic from the internet would be routed directly to your DMZ.
Therefore if any hacker where to compromise a machine within the DMZ, then the only network they would have access to would be the DMZ. The hacker would have little or no access to the LAN. It would also be the case that any virus infection or other security compromise within the LAN would not be able to migrate to the DMZ.

In order for the DMZ to be effective, you will have to keep the traffic between the LAN and the DMZ to a minimum. In the majority of cases, the only traffic required between the LAN and the DMZ is FTP. If you do not have physical access to the servers, you will also need some sort of remote management protocol such as terminal services or VNC.

Database servers

If your web servers require access to a database server, then you will need to consider where to place your database. The most secure place to locate a database server is to create yet another physically separate network called the secure zone, and to place the database server there.
The Secure zone is also a physically separate network connected directly to the firewall. The Secure zone is by definition the most secure place on the network. The only access to or from the secure zone would be the database connection from the DMZ (and LAN if required).

Exceptions to the rule

The dilemma faced by network engineers is where to put the email server. It requires SMTP connection to the internet, yet it also requires domain access from the LAN. If you where to place this server in the DMZ, the domain traffic would compromise the integrity of the DMZ, making it simply an extension of the LAN. Therefore in our opinion, the only place you can put an email server is on the LAN and allow SMTP traffic into this server. However we would recommend against allowing any form of HTTP access into this server. If your users require access to their mail from outside the network, it would be far more secure to look at some form of VPN solution. (with the firewall handling the VPN connections. LAN based VPN servers allow the VPN traffic onto the network before it is authenticated, which is never a good thing.)

WiFi is the wireless way to handle networking. It is also known as 802.11 networking and wireless networking. The big advantage of WiFi is its simplicity. You can connect computers anywhere in your home or office without the need for wires. The computers connect to the network using radio signals, and computers can be up to 100 feet or so apart. So, in the spirit of spreading the word, I’m going to give you some great reasons why you need a wireless network.

Sharing Internet Access.

Wireless networking gives you a cheap and easy way to share one Internet connection between multiple computers, eliminating the need for more than one modem. You can even add new computers to your network simply by plugging in a wireless card and switching them on — they get an Internet connection straightaway! There aren’t many wired networks that can say that.

Sharing Files and Printers.

A wireless network gives you access to your files wherever you are in your home, and makes it easy to synchronise the data on a laptop with a home computer. It is much easier to send files between computers with a wireless network than it is to send them by email, or even by burning them to a CD.

Plus, with the printer connected, you can also write things wherever you want, press print, and go and collect them from a printer connected to another computer — printers that are plugged into one of the computers on the network are shared between all the computers automatically.

Always On Connection

A big factor in the spread of broadband was that it let Internet connections be always-on, without needing to dial in. Well, wireless networking lets network connections be always-on, meaning that any of your computers can connect to the Internet whenever you want! You can take laptops from room to room, and it doesn’t matter — they’ll always have access. Plus, there’s not even any need to set up a username and password system, as wireless networks work without logging in. It’s just so convenient!

No More Wires.

This, of course, is the biggest reason why you should switch your network over to wireless. Wires are inconvenient, expensive, ugly and dangerous — you’ll be delighted to see the back of them.

The average Ethernet wire doesn’t cost that much per metre, but once you’ve bought enough metres to do whatever you need to do, well, it tends to add up quickly. Not only that, but if you want to run your wire between rooms or floors, you have to knock holes in the walls — which might not even be allowed if you’re renting. I know plenty of people in rented apartments who had to keep their network confined to one room until they went wireless. With wireless networking, well, you can even take your computer outside, if you want to!

No more wires also means no more spaghetti all over the floor and in the corners. Not only does this improve the safety of your home, as it’s all too easy to trip over exposed wires, but it also means that you don’t have to go to all the trouble of packing all the wires up and re-connecting them at the other end when you move. It also means that you don’t have to examine every wire for damage if your Internet connection breaks down.

Play LAN and Internet Games.

You might have seen an option in your favourite game to play over a LAN. Well, wireless networks are LANs, which means that your whole family can play that game together — without needing the computers to be anywhere near each other. It’s far more fun to play against real people you know than to play against random people over the Internet, not to mention that the game will work much faster. You could even invite your friends to bring their computers and join in — a ‘LAN party’!

An added benefit is that wireless equipment lets you easily connect any games consoles you or your kids might have to the Internet, and start playing online. It’s far easier to play online with a wirelessly connected Xbox or PlayStation 2 than to have to connect it to your modem every time.

Convinced Yet?

If you’re excited, then that’s great — keep reading these articles for advice on how to set everything up. If you don’t think it’s for you yet, well, don’t give up on it — I’m sure you’ll come round when you realise just how easy and cheap wireless really is.