The Complete Guide to Metropolitan Area Networks (MAN Networks)

There are many differing types of area networks available for networking purposes, with the metropolitan area network being among them. If you’re a novice to computer networking, it does help to know the differences between each computer network available.

Metropolitan area networks are somewhat rarer to encounter for the common IT professional, but you interact with them on a daily basis. As with any new subject, there is a fair bit to explore and understand when it comes to MANs. This guide is meant to give useful and actionable information about MANs.

As well as let you know what constitutes one, and where they are used in common applications. This is a higher-level guide, so networking students may find some of this a bit of a rehash of common concepts.

What is an Area Network

An area network refers to interconnected devices. At its purest distillation, a network is simply two or more devices that can intercommunication with each other. If you have a Bluetooth headset and a phone, once connected these are an area network. In networking jargon, this would be a personal area network or PAN.

Area networks run the gamut from very small to very large. Personal area networks typically cover the area of a room or a smaller office, accounting for around 33 feet of transit distance. Local area networks are larger and can range up to a mile or so.

Metropolitan area networks, or MANs, are the second largest of the area networks. They range from 2 miles up to 25 miles, the size of a city more or less. Beyond MANs are wide area networks, or WANs. Think of this one as internet coverage for a county and you aren’t far off the mark.

What Makes a Metropolitan Area Network

Metropolitan area networks are wide-spanning networks that interconnect nodes with a transit distance roughly the size of a typical city. Multiple local area networks make up a typical MAN, like multiple offices or homes, and their own routers and switches.

With this in mind, these local area networks appear as little more than single points to a MAN, however. A metropolitan area network might serve as internet coverage for a city or town. As previously mentioned, each implementation of an area network is meant for intercommunication.

These individual nodes, or LANs, is like a local area network spread across miles of coverage. Multiple metropolitan area networks will make up a WAN, accounting for internet coverage across a whole county.

MANs do have drawbacks, however. As with any network implementation, there can be congestion if all nodes are transmitting at the same time. From an infrastructural standpoint, they’re immensely expensive. Some ISPs might opt for establishing a WAN instead of a MAN to cover a given area.

Maintaining a MAN can prove to be difficult as well, given the limited geographical scope. There are inherent advantages to metropolitan area networks, however.

Users might experience faster transmission, due to the shorter distance between nodes. They also cover a far larger area than a LAN, meaning data can travel much further before reaching an endpoint.

Common Usages

Metropolitan area networks do have practical applications. You will likely find them as the means of connecting government offices, especially within the same general area. If your city has more than one office meant to service the Department of Social Services, the Department of Motor Vehicles, and so on, they are likely connected via MAN.

College campuses will typically incorporate campus area networks or CANs that then go to a metropolitan area network. If you or your child’s main college campus has an admissions office or something of the like off-campus, it might be connected through a MAN.

As previously mentioned, metropolitan area networks can serve as a means for internet connectivity for an area. Local ISPs might opt for establishing one in lieu of connecting an area to a wide area network. This is a rarer usage, especially with the many large national-level internet service providers around.

Typically, a metropolitan area network will connect larger local area networks together, rather than serving as the means of internet access for a community.

How is a Metropolitan Area Network Built?

Metropolitan area networks aren’t going to rely on standard ethernet cabling to get the job done. You might think something like CAT5 or CAT5e cabling would suffice, but the signal degradation is too great over larger distances. A metropolitan area network will instead rely on more robust transmission mediums to carry a signal.

If you’re familiar with coaxial or fiber optic cables, these are the typical means used to connect a MAN. Part of the reasoning behind this is that they offer far better signal strength over longer distances. A CAT5 cable can span an office building at most, but coaxial cabling can carry a signal for miles before signal strength is lost.

Endpoint devices might be switches, routers, or modems, depending on the intention of the metropolitan area network. Local internet service is going to typically rely upon a modem for carrying a signal from node to node. A MAN meant to interconnect offices with miles between them might rely on a specialized switch or router that incorporates the functions of a modem, however.

Establishing a metropolitan area network can be a very costly endeavor. As you might expect, running miles of cabling is not a cheap proposal for any company.

In organizations where miles might separate offices, they may instead opt for establishing a virtual private network, or VPN, and rely on the local wide area network to establish a connection. This helps to keep the costs down while providing a means of intercommunication between two or more remote locations.

Metropolitan Area Networks vs. Wide Area Networks

With all this in mind, why would you implement a WAN over a MAN? Part of it comes down to cost considerations. While developing the infrastructure behind a wide area network isn’t cheap, it is something most internet service providers are going to account for when developing an area.

Transmission speeds are typically a bit slower when using a WAN, but the increase in speed isn’t going to be a consideration for most WANs. The larger area coverage from endpoint to endpoint, however, means that a WAN can scale and establish intercommunication with other WANs.

Metropolitan area networks are expensive, as you’re essentially establishing a small internet service provider to develop one. Most newer companies utilizing wired connectivity are typically going to opt for a WAN connection.

Implementing VPN connections between distant sites is far cheaper than building out separate infrastructure. It might cost a company thousands to license and implement a VPN to connect sites, but building out cabling could cost millions.

Closing Thoughts

A metropolitan area network is just one of many types of area networks. It has a limited scope in which it can be effectively deployed, like any area network. That said, they do have a very specific utility. While they can be an expensive solution to a problem, MANs are highly performant networks.

As with any area network, it really does boil down to the cost of the implementation. Building out any computer network is less a question of what the best-performing option is, and more a question of what the most cost-effective means of establishing interconnectivity might be.

As such, metropolitan area networks are one of the rare implementations of an area network. They may have been the method of choice for communicating between businesses decades ago, but technology has advanced to the point where wide-area networks have largely replaced them in common usage.

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