The categorization of a network is closely associated with its size and location. In this video, you’ll learn about LANs, WANs, PANs, SANs, and WLANs.
If you’re plugging into an Ethernet connection or using a local 802.11 wireless network, then you are communicating over a Local Area Network, or a LAN. We usually refer to a LAN as a group of networks that are close to our location, so this might be on the floor of a building or in a group of buildings that make up this particular local area network.
One of the common characteristics of a LAN is that we usually get our fastest speeds by a local area network. If we’re connecting to networks that are farther away, then we’re probably not on a local area network anymore, and therefore, we’re not getting those same high throughputs.
If you’re connecting to a location that’s in another city, another state, another country, or anywhere around the world, then you’re communicating over a Wide Area Network, or a WAN. Because of the challenges associated with communicating over such long distances, wide area networks tend to be a bit slower than communicating over a LAN.
There also might be many different technologies used to be able to communicate over this wide area network. For example, you might be communicating using point-to-point serial connections, or it might be an MPLS network, or Multiprotocol Label Switching network.
And some wide area networks may use communication facilities here on Earth. We refer to these as terrestrial networks. Or we might use satellites to communicate across the WAN. Those would be non-terrestrial networks.
We’ve also created specialized networks for devices and components that are close to us as individuals. We refer to these as a PAN, or Personal Area Network. If you’re communicating with Bluetooth, infrared, or near-field communication, you’re probably communicating over a PAN.
We might be using a personal area network inside of our vehicle to have audio output from our phone and be able to communicate hands-free. Or it may be integrating with the media services that are already on your existing mobile device.
Many of the wireless headsets that we use these days are communicating using Bluetooth. That certainly would be a personal area network protocol. And some of the health-related technologies we use also use a personal area network. So if you’re gathering health details on your smartphone or you’re communicating directly to your workout devices, then you’re probably using a personal area network.
We’ve talked about a local area network, and we’ve talked about a wide area network, but there is a network that sits in the middle of those two. That would be a Metropolitan Area Network, or a MAN. This is a network that tends to be in a single geographical area, such as a city. If we have a lot of remote locations around the same city, we can usually connect to those using a metropolitan area network.
Traditionally, these metropolitan area networks have been proprietary. But increasingly, we’ve seen these standardize on Ethernet, specifically Metro Ethernet, which describes a type of Ethernet connectivity in our local city.
And you might also find that your local government has put their own fiber into the ground. Since they do have right of way, they’re able to put anything they would like inside of the pipes. And they can create their own metropolitan area network using their own fiber.
Many organizations will have a repository of storage that they refer to as a SAN, or Storage Area Network. This is usually a high-speed connectivity because we’re often transferring large amounts of data into and out of that SAN.
To the devices accessing the SAN, this looks and feels like a local storage device. So you can even take a very large file and change a very small bit of data within that file very, very efficiently. We refer to this as block-level access. Because we’re moving so much data in and out of the SAN, we’re usually putting these on their own isolated network, connected to the rest of the network over very high-speed connections.
And in our homes and businesses, we often will install wireless networks that are 802.11 technology, referred to as WLAN, or Wireless LAN. These allow you to move around your local area and still have access to all of the resources you need over your mobile devices, your laptops, or anything else that’s using this wireless network. And if you’re working in multiple buildings or a larger campus area, you can add additional access points to expand the reach of your wireless local area network.