Types of Networks: LAN, WAN, WLAN, MAN, SAN, PAN, EPN & VPN - Video & Lesson Transcript | Study.com

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Personal Area Network

A personal area network, or PAN, is a computer network organized around an individual person within a single building. This could be inside a small office or residence. A typical PAN would include one or more computers, telephones, peripheral devices, video game consoles and other personal entertainment devices.

If multiple individuals use the same network within a residence, the network is sometimes referred to as a home area network, or HAN. In a very typical setup, a residence will have a single wired Internet connection connected to a modem. This modem then provides both wired and wireless connections for multiple devices. The network is typically managed from a single computer but can be accessed from any device.

This type of network provides great flexibility. For example, it allows you to:

Send a document to the printer in the office upstairs while you are sitting on the couch with your laptop.
Upload a photo from your cell phone to your desktop computer.
Watch movies from an online streaming service to your TV.

If this sounds familiar to you, you likely have a PAN in your house without having called it by its name.

Local Area Network

A local area network, or LAN, consists of a computer network at a single site, typically an individual office building. A LAN is very useful for sharing resources, such as data storage and printers. LANs can be built with relatively inexpensive hardware, such as hubs, network adapters and Ethernet cables.

The smallest LAN may only use two computers, while larger LANs can accommodate thousands of computers. A LAN typically relies mostly on wired connections for increased speed and security, but wireless connections can also be part of a LAN. High speed and relatively low cost are the defining characteristics of LANs.

LANs are typically used for single sites where people need to share resources among themselves but not with the rest of the outside world. Think of an office building where everybody should be able to access files on a central server or be able to print a document to one or more central printers. Those tasks should be easy for everybody working in the same office, but you would not want somebody just walking outside to be able to send a document to the printer from their cell phone! If a local area network, or LAN, is entirely wireless, it is referred to as a wireless local area network, or WLAN.

Metropolitan Area Network

A metropolitan area network, or MAN, consists of a computer network across an entire city, college campus or small region. A MAN is larger than a LAN, which is typically limited to a single building or site. Depending on the configuration, this type of network can cover an area from several miles to tens of miles. A MAN is often used to connect several LANs together to form a bigger network. When this type of network is specifically designed for a college campus, it is sometimes referred to as a campus area network, or CAN.

Wide Area Network

A wide area network, or WAN, occupies a very large area, such as an entire country or the entire world. A WAN can contain multiple smaller networks, such as LANs or MANs. The Internet is the best-known example of a public WAN.

A WAN can be setup both physically and virtually. A WAN can connect multiple other LANs virtually, creating what is called a VLAN. In this sense it is like a LAN of LANs!

When it comes to today’s increased use of remote work connections, the WAN is a powerful tool that provides interfaces to the Internet as well as giving access to systems that may be spread throughout the world.

One means of connecting to a WAN is through a VPN or virtual private network. This allows a secure connection to the WAN, thus protecting your data and device from attack.

In addition to virtual connections, fiber optic provides a backbone to many WAN setups.

Private Networks

One of the benefits of networks like PAN and LAN is that they can be kept entirely private by restricting some communications to the connections within the network. This means that those communications never go over the Internet.

For example, using a LAN, an employee is able to establish a fast and secure connection to a company database without encryption since none of the communications between the employee’s computer and the database on the server leave the LAN. But, what happens if the same employee wants to use the database from a remote location? What you need is a private network.

One approach to a private network is to build an enterprise private network, or EPN. An EPN is a computer network that is entirely controlled by one organization, and it is used to connect multiple locations. Historically, telecommunications companies, like AT&T, operated their own network, separate from the public Internet. EPNs are still fairly common in certain sectors where security is of the highest concern. For example, a number of health facilities may establish their own network between multiple sites to have full control over the confidentiality of patient records.

With the growth of the Internet, private networks have gone virtual. A virtual private network, or VPN, extends a private network into a public network, such as the Internet. A VPN is a network in which some parts of the network use the Internet, but data is encrypted before it is sent over the Internet to indicate that it is a private network. A VPN provides a high level of security for traffic over the Internet.

Other Special Purpose Networks

Most computer networks are general purpose networks used for many different forms of communication, but some networks have been built for a very specific purpose.

A storage area network, or SAN, is a network dedicated to data storage. A large organization may have different types of centralized storage, not all of which should be accessible to all users of the local area network within the organization. A dedicated SAN gives network and database administrators more control over data storage. Regular LAN users only get access to the elements of this storage system that are relevant to them.

A home area network, or HAN, is a type of PAN specifically designed for home use. A home network may include things like digital televisions, home security and other types of systems that are unique to the home environment and not typically found in an office.

A body area network, or BAN, is a network of wearable computing devices. This can include things like a watch, special glasses, tracking devices and heart-rate monitors. For example, an Alzheimer’s patient could be outfitted with a location tracking device and a cellular communication device. If they leave a certain area, family members can be alerted with a text or e-mail message to the location of their loved one.

Lesson Summary

Computer networks can be characterized in the term of the geographic area they occupy and the purpose of the network within this geographic area. Networks can cover anything from a handful of devices within a single room to millions of devices spread across the entire globe.

A personal area network is a computer network organized around an individual person within a single building. A local area network consists of a computer network at a single site for sharing resources, typically an individual office building.

A metropolitan area network consists of a computer network across an entire city, college campus or small region. A wide area network occupies a very large area, such as an entire country or the entire world. Special purpose networks include storage area networks, home area networks and body area networks.