Bandwidth: The maximum data transfer rate of a network connection.

There is a common misconception that bandwidth measures the speed of data transfer between connections. While it is true that bandwidth measures speed, it does not measure the speed of the data itself. In fact, the movement of the data is so fast it is negligible.

What bandwidth really measures is the rate of the transfer, or how much data can flow through the connection at any given time. This rate is most often measured in mbps- megabits per second. Different connections can handle different bandwidths.

For example, an Ethernet connection can handle about 1000 mbps, vs. a cable modem which can handle only 25. This is where the confusion in bandwidth generally comes in. All connections are not made equal, some can handle massive quantities of data, and others can barely handle everyday use.

Therefore, when transferring data from a connection with a large bandwidth to a location with a smaller bandwidth, there can be a bottleneck effect which slows the rate.

Think of the old adage, “Only as strong as the weakest link.” The transfer rate is determined by the connection with the smallest bandwidth. Often the weakest link is the users ISP router. The simplest analogy is to imagine an hourglass with the top filled all the way with sand.

If the tube in the middle is small, the grains will fall through slowly. If it is large, they will pass right through. This speed is why many people often assume bandwidth means data speed, when the truth is they are not observing individual speeds, but a collective rate determined by their connection capacity.

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