What is Bandwidth Throttling?

What is Bandwidth Throttling & Why Do Some Companies Do It?

Bandwidth throttling
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Bandwidth throttling is a purposeful slowing of available bandwidth.

In other words, and in general, it's an intentional lowering of the "speed" that's typically available over an Internet connection.

Bandwidth throttling can happen at various places between your device (like your computer or smartphone) and the website or service that you're using over the Internet.

Why Would Anyone Want to Throttle Bandwidth?

You as the user of an Internet connection or service rarely benefitĀ from bandwidth throttling.

Very simply, bandwidth throttling means limiting how fast you can access something when online.

Companies along the path between you and your web-based destination, on the other hand, often have much to gain from bandwidth throttling.

For example, an ISP might throttle bandwidth during certain times of the day to decrease congestion over their network, which lowers the amount of data they have to process at once, saving them the need to buy more and faster equipment to handle Internet traffic at that level.

While very controversial, ISPs also sometimes throttle bandwidth only when the traffic on the network is of a certain kind or from a certain website. For example, an ISP might throttle the bandwidth of a user only when heavy amounts of data is being downloaded from Netflix or uploaded to a torrent website.

Sometimes, too, an ISP will throttle all types of traffic for a user after a certain threshold has been reached.

This is one way they "lightly" enforce the written, or sometimes unwritten, bandwidth caps that exist with some ISP's connection plans.

ISP-based bandwidth throttling is most common, but it can also happen inside business networks. For example, your computer at work may have an artificial limit placed on its connection to the Internet because the system administrators decided to put one there.

On the other end of the spectrum, sometimes an end-service itself will throttle bandwidth. For example, a cloud backup service might throttle bandwidth during the large initial upload of your data to their servers, drastically slowing down your backup time but saving them a lot of money.

Similarly, Massively Multiplayer Online Game (MMOG) services might also throttle bandwidth at certain times to prevent their services from overloading and crashing.

How Do I Tell if My Bandwidth is Being Throttled?

If you suspect that your ISP is throttling bandwidth because you've been reaching a monthly threshold, an Internet speed test done several times throughout the month might shed light on that. If your bandwidth suddenly decreases near the end of the month then this might be happening.

ISP bandwidth throttling that's based on the type of traffic, like torrent use or Netflix streaming, can be tested with some certainty with Glasnost, a free traffic-shaping test.

Other types of bandwidth throttling are harder to test for. If you suspect the company network has some throttling enabled, just ask your friendly office IT person.

Any bandwidth throttling at the far end, like an MMOG, a cloud backup service, etc., is probably explained somewhere in the service's help documentation.

If you can't find anything, just ask them.

Is There a Way to Avoid Bandwidth Throttling?

Virtual Private Network services are sometimes helpful to circumvent bandwidth throttling, especially if it's your ISP that's doing it.

VPN services hide the kind of traffic that's flowing between your network at home and the rest of the Internet. So, for example, on a VPN, your 10 hour per day Netflix binge watching that used to get your connection throttled now doesn't look like Netflix to your ISP.

Any local bandwidth throttling by your network administrators at work are less avoidable, if not impossible, most likely because you also probably aren't allowed to use a VPN service, which requires making certain changes to your computer.

Even harder to avoid is throttling at the end-point, the kind that's enforced by the service you're connecting to or using.

So, for example, if this was a concern for you with an online backup service, your best bet from the beginning would be to choose one that doesn't do that.