MAN: Definition & How It Compares to a LAN

A metropolitan area network (or MAN) is a form of computer network that connects resources within one geographic region.

MAN is sometimes (redundantly) called "MAN network" or a "MAN network computer." No matter what you call it, a MAN can be a powerful tool if you hope to connect a large group of users to resources within a geographic area with clear boundaries you can define.

What is a MAN?

A MAN is a network made up of several smaller networks, all connected through a mixture of wireless technology and cables.

Let's start with an example.

We know that modern office buildings are getting bigger and bigger. But we're not building many more of them. If you own an office building and outgrow your space, your best option is to buy or rent another building near you. How can you keep employees in that building connected to your resources with lightning-fast speed?

A MAN can do that work for you. Invest in the infrastructure, and you'll link the networks that support both buildings into one cohesive whole. 

This is just one type of MAN. You could also use the concept to:

• Connect cities. A mayor with deep pockets could give all constituents access to free WiFi through a MAN. 
• Link different businesses. As a cost-saving measure, you could build a MAN with a completely different organization. 
• Run an efficient government. A MAN could also help a city interconnect resources, including wireless appliances and devices.

The geographic vicinity is critical to a MAN. You'll need to link items via cables, and they can't run long distances without becoming too costly. A MAN, by definition, is small.

What sets a MAN apart?

Plenty of network types exist, and most help devices link up if they are near one another. A MAN is slightly different than others you've likely heard of before.

A MAN is often confused with:

• CAN. A campus-area network (or CAN) links all of the buildings on a campus together. A CAN is a form of MAN, and for students, the connection is critical. Some 17 million students don't have an internet connection at home. A CAN helps them stay in touch while on campus. 
• LAN. A local area network (or LAN) is a collection of devices that are all connected in one location. Several LANs are pulled together to make up one MAN. 
• WAN. A wide-area network (or WAN) is a connection of devices scattered across vast distances. A WAN is much larger than a MAN.

It's easy to get confused by all the acronyms involved in computing. But know that a MAN does things these other networks can't.

How are MANs constructed?

Several smaller LANs must come together to form one MAN to serve all interested parties. Typically, wires make those connections. 

Ethernet runs and fibers can do the work. But if that's not possible, administrators can lean on point-to-point WiFi, wireless LAN, or private 5G networks to maintain a connection.

MANs rely on internet exchange points. An independent switch like this operates more efficiently when traffic zooms between networks, meaning fewer delays and issues for users.

How to protect a MAN in networking

A MAN can keep your users connected to your resources and servers. But that system also comes with plenty of access points, and each could be an open door for a hacker. 

Some MAN systems have been implicated in man-in-the-middle attacks, where a hacker watches (and sometimes changes) all data that enter and exit a specific point on the server. Distributed denial of service attacks can also target MANs. 

These risks shouldn't dissuade you from using a MAN. If you have several buildings and plenty of access points, interconnectivity is crucial. But you should know your threat landscape and respond accordingly. 

We have an exceptional security insights piece about protections at the admin, user, and network levels. We encourage you to check it out for more ideas on how to keep your assets safe.

References

Average Size of New Commercial Buildings in United States Continues to Grow. (May 2015). U.S. Energy Information Administration. 

17 Million Students Lack Home Internet. (August 2020). The 74. 

Promoting the Use of Internet Exchange Points: A Guide to Policy, Management, and Technical Issues. (December 2012). Internet Society.