Computer networks are a part of most homes and businesses. If you connect to the Internet, you are technically connecting to a network. For security and efficiency, it’s best to understand how networking works before connecting all of your important computers to shared resources and especially the Internet.
Types of Networks
If you want to network your home or office, you want to build one of the most common types of networks: a local area network (LAN). LANs can consist of two or more computers and devices, but these computers and devices are located in the same general area. For instance, you might have an office of 100 employees and several printers. This is a LAN. Networking computers in your home is also a LAN.
The other common networking type is the Internet. The Internet is really just one large network consisting of servers, data centers, routers and other devices. The Internet is open to the public, which is what makes it considerably different than a LAN.
Wide area networks (WANs) are basically multiple LANs linked together by some device. WANs are connected using satellite, point-to-point devices or telephony equipment. You typically use a WAN when you have multiple offices located in different locations and need them to connect for collaboration between employees.
Intranets are less common but popular in larger corporations. Intranets are internal networks usually for sharing documents, company information and news through the employees’ browser. The company uses web servers with collaboration software. For instance, Microsoft Sharepoint is a common tool used to host intranets. Employees log in to the Sharepoint website to download important documents, read the latest news and update any personal information used for company purposes.
Extranets are the final type of network. Extranets are expanded intranets. The only difference between an intranet and an extranet is security. An intranet is only available to internal employees. An extranet is an expanded intranet that makes some of the information available to the public over the Internet. For instance, a company could use an intranet for software documentation for employees, but this same information could be available to the public using the extranet.
Years ago, networking equipment was usually just printers, routers, switches and servers. Now, networking equipment can be mobile devices, Wi-Fi hotspot hardware and other mobile resources. Network administrators also need to account for mobile device support such as tablets and smartphones.
Probably most common networking equipment hardware is a router. A router connects multiple networks together. These segmented networks are referred to as subnets. A subnet lets you segment and expand your network beyond the physical location. Driving traffic to the right subnet is done using routers. Routers have a list of IP tables, security configurations, DHCP and wireless or wired connections to connect all of your computers and hardware resources. You can buy a router at a local hardware store. If you have Internet in your home or office, you probably have a cable or DSL router. The router connects to your ISP’s servers and allows you to access the Internet using the ISP resources.
Hubs or switches are secondary to routers. You can also have a hub in your small network. Hubs aren’t “intelligent” devices. Hubs connect computer devices just like routers. However, hubs don’t have any intelligent routing such as DHCP, IP tables, routing traffic or security. For instance, you could use a hub to connect an older printer with no network card. All computers on the network can access the printer through shared resources on the computer on which the printer is connected.
Another part of networking equipment is a network card. You need a network card that matches the protocol you use on the network. Protocols are the “language” or “language rules” used for computers to communicate. The network card is the gateway between the network connection and the computer’s CPU. You need a network card for computers and devices such as printers. Network cards can be wireless or wired, depending on the type of network you set up.
As mentioned above, networking protocols are the rules for the routing “language.” The most common set of protocols is the Internet protocol set. The basic protocol used on the Internet is TCP/IP. TCP/IP is a set of protocols that allow you to connect devices, transfer your request to web servers and read web pages. Other, older protocols can also be used on a network, but doing so just makes your network more cumbersome since you need TCP/IP anyway to connect to the Internet.
You can use applications on the Internet to read and “understand” information. For instance, the HyperText Transfer Protocol (HTTP) is what you use to read web pages. HTTP is plain text sent over the Internet, so your browser can then read and parse the website information. HTTP has HTTPS, which is a security protocol that encrypts data. This adds a security layer to HTTP, so your private data such as medication information, financial data such as credit cards and login information are sent with encryption.
When you send information over the Internet, your data is packaged with several piece of information such as the source IP (your computer’s IP address) and the destination IP address (where you want to connect to).
This information is very basic compared to the more complex application and administration of computer networks. Security is one main concern when using a large network that also has a connection to a public-facing network such as the Internet. When you determine that you want to set up a computer network, you can read more information in the documentation for your equipment. Networking is not difficult with the amount of manufacturers creating support documentation to help you get started. After you create a small network, make sure you take the time to understand security to protect your private data.