A Nesting Doll of Networks: Types of Networks

  PAN, WAN, MAN, LAN, CAN - what is up with all these rhyming words? As much as I would love to have a walk down memory lane and make a right at Kindergarten Avenue, these are actual names - well, acronyms, - for the types of networks that exist today. These networks are like nesting dolls. PANs can be found in LANs, LANs make up our WANs, and there is more in between. Let's take a closer look at these networking nesting dolls.

Personal Area Networks (PANs)

Have you ever grown frustrated at how your Bluetooth headphones seem to take forever to pair to your phone? Do you use a wired mouse or a wireless mouse with your desktop? Do you use your smartphone for payment by "tapping" it? These are examples of personal area networks. 

A personal area network connects devices close in range, from a few centimeters to a few meters in range. These types of networks can be wired or wireless. A wired PAN may be a computer connected to a printer by a USB cable or Ethernet cable. A wireless PAN may use communication methods, such as Bluetooth, infrared, or radio waves. Wireless earbuds communicate with your phone, laptop, or other device using Bluetooth, where the pairing process is not always so seamless, but I digress. 

Other than being small, PANs do not consume as much energy as the other types of networks. Smart home devices, such as thermostats or door locks, do not consume much power, using other wireless methods such as Zigbee or Z-Wave. Some of these devices are even powered by a battery. 

As being small means less space taken up, that is also a PAN's weakness. Have you ever had your earbuds in and as you walk out the house without, the sounds become garbled? Bluetooth has a distance limitation - 30 feet. Depending on the connection method, data transfer can also be slow. You can use an Ethernet cable between your computer to a printer, but sending a file over Bluetooth is significantly slower. When you tap your phone to make a transaction, it is more fitting because it is quick and short-range. If you are looking for speed, look at the next nesting doll.

Local Area Networks (LANs)

Several personal area networks can come together to create a local area network. While PANs have their personal space - hence the name - a local area network knows how to branch out. 

A local area network has more range than a personal area network.  LANs are often associated within a single small or distinct area. For example, your own home has a local area network. A building can have a LAN for every floor, and a workplace can have a LAN for each department. Since it covers more space, you are going to need connection methods that have more range and power. Bluetooth will not cut it alone. We have reached wireless fidelity - Wi-Fi! Local area networks can also be wired. This is where we get to the networking hardware, such as routers, switches, access points - but more on that later. 

A local area network often uses Ethernet cables. Ethernet is a networking protocol that allows devices to communicate with each other. Depending on the type of cable, you will have more range and speed. Either way, LANs are great for transfers between devices and connecting many devices.

A local area network can also use a wireless method to connect devices in an area. This type of network is called a wireless LAN, or a WLAN. Commonly, this is done by radio transmission media, such as Wi-Fi. In homes, offices, schools, and other places, there are often a combination of wired and wireless connections to form a LAN. Think about within a house. A house can have several smart devices, such as TVs, cameras, lights, and refrigerators, and other devices, such as a computer, printer, smart phones, and gaming consoles. This local area network may use a wireless access point, so devices that have Wi-Fi capabilities can connect wirelessly. Smart devices, such as an Amazon Alexa, need to reach the Internet to access news stories and give you the weather. In order for our devices to reach the Internet, we have routers in our homes that take our requests through several "checkpoints" - or other routers - to get to a site. More on this on a future post!

Just like PANs, LANs are still limited in geographic range. Ethernet is a protocol, so it has rules. When creating a LAN with Ethernet, the signal degrades after approximately 300 feet before adding "aid" to carry that signal any further. A LAN require more maintenance and planning than a PAN, such as considering the type of cable, how much of it, and how many devices will be operating on that network. 

You can group LANs to create even bigger networks, such as CANs and MANs. 

Campus Area Networks (CANs)

The first word says much - campus. A business park or a school campus may have a campus area network. A campus area network consists of several LANs connected across multiple buildings or sections within a certain area. With a bigger population and more distance, these types of networks can use fiber optic cabling to connect buildings and deal with more traffic than a normal LAN would encounter. 

Metropolitan Area Networks (MANs)

Once again, the first word says much - metropolitan. A metropolitan area network can consist of several LANs and CANs spanning a vast public area, such as a city. Like campus area networks, MANs can use fiber optic cabling to connect buildings and deal with the amount of traffic. In these networks, you may see cell towers to provide enough coverage for all those within populated areas. 

Wide Area Networks (WANs)

So far, PANs are one of the smallest types of networks. You can group several PANs to create a LAN. Then, you can group several LANs to create CANs and MANs, all depending on the range you are going for. What happens if you group all these together? By all, I mean every network in the world. You get the Internet - the biggest wide area network of them all. 

A wide area network is a type of network that consists of all types of networks across a vast distance. The Internet is a prime example. The Internet is more than just going to Google and finding who won last night's game. The Internet consists of all different devices, files, and applications in the world that users interact with. Another example of a WAN may be a headquarters of a business and its main offices in different cities across a country. This restricted, internal type of wide area network is called an intranet.  

WANs are often connected by long-range connections, such as fiber optics, satellite, cellular, and radio. In my co-op iteration with Motorola Solutions, I was introduced to the extensive system of radio communications and critical infrastructure across counties and within different cities. Through microwave and radio links, subsites are able to transmit and receive signals from subscribers, or radios. There are more within the system, but this would be an example of a WAN using radio waves and microwaves as a transmission media. 

Putting it All Together

Here is a conceptual example of PANs, LANs, and WANs within an office environment. In the personal area network, two computers and the office computer and office speaker are able to communicate with each other via Bluetooth. Both sides of the connection have a local area network. The computers are connected to a switch which are then connected to a router. There is a local main office router and a remote router that is for an office in Miami. To connect the two LANs, there is an intermediate router. When these two offices communicate over a long distance, a WAN is formed.  

This is a simplified look of the types of networks without going in-depth with the actual hardware. That will be in a future post. Yet, these networks expand to include more devices, more range, and more traffic. When you open a network (or a cabinet with all the networking hardware), we are actually seeing one nesting doll amongst others. When it is all unraveled, each type of network has its own design just like one of those nesting dolls. However, an important aspect of network design is handling traffic. How is that done? Stay tuned.