Difference Between Bandwidth and Data Rate

Bandwidth vs Data Rate

在谈到network connections, sometimes, the two terms ‘bandwidth’ and ‘data rate’ are used with the same meaning of data transfer rate (or bit rate). It is related to the amount of data being transferred within a second. However, bandwidth and data rate have different meanings in networking and communications.

Bandwidth

In communications, bandwidth is the difference between highest and lowest of the frequency range used for signaling. It is measured in Hertz (Hz). Bandwidth has the same meaning also in electronics, signal processing, and optics.

For a network connection, bandwidth is the maximum amount of data that can be transferred within a unit time. It is measured in the unit ‘bits per second’ or bps. For example, bandwidth of Gigabit Ethernet is 1Gbps. Bit is the basic unit of measuring information. Value of a bit can be ‘0’ or ‘1’ (or ‘true’ or ‘false’). For example, to represent the number 6 (in decimal) in binary, we need 3 bits as six is 110 in binary.

Data Rate

Data rate (or data transfer rate) is the amount of data being transferred through a connection within a second. Data rate cannot be higher than the bandwidth of the connection. Data rate is also measured in ‘bits per second’ or bps. Sometimes data rate is also called as bit rate.

What is the difference between bandwidth and data rate? 1. In communications, bandwidth is measured in Hz and it is measured in ‘bps’ (kbps, Mbps etc) for network connections. However data rate is only measured in ‘bps’ 2. For a given network data transfer, data rate cannot be higher than the bandwidth of the network connection. 3. In communications, bandwidth (in Hz) and data rate (bits per second) are related to each other by Shannon–Hartley law.