What Is a Bandwidth Cap?

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Internet Service Providers (ISPs) sometimes place limits on the amount of data customers can send and/or receive over their Internet connections. These are often called bandwidth caps.

Monthly Data Quotas

Comcast, one of the largest ISPs in the U.S., instituted a monthly quota for its residential customers starting in October 2008. Comcast caps each customer to a total of 250 gigabytes (GB) of traffic (combination of downloads and uploads) per month. Except for Comcast, Internet providers in the United States typically do not impose monthly data quotas although the process tends to be more common in some other countries.

Bandwidth Throttling

Service plans for broadband Internet access normally rate their connection speed as a certain bandwidth level like 1 Mbps or 5 Mbps. Besides maintaining connections that regularly achieve the advertised data rate, some broadband providers put additional technology into their network to actively prevent connections from going faster than their rating. This type of throttling is managed by the broadband modem.

Bandwidth throttling can be applied dynamically on a network, such as to limit connection speeds during certain times of the day.

Bandwidth throttling may also be performed by providers on a per-application basis. ISPs have most notably targeted peer to peer (P2P) applications for throttling, which due to their popularity can overload their networks. To help file sharers keep within reasonable usage limits, all popular P2P applications include options for throttling the bandwidth they consume.

Other Types of Bandwidth Caps

Old, low-speed Internet connections dialup are not bandwidth throttled but instead are inherently limited by their modem technology to 56 Kbps speeds.

Individuals may have temporary, personal bandwidth limits applied to their accounts as disciplinary action by providers.