What Is Bandwidth?

Bandwidth is the data transfer capacity of a computer network in bits per second (Bps). The term may also be used colloquially to indicate a person's capacity for tasks or deep thoughts at a point in time.

Key Takeaways

  • Bandwidth is a measure of how much information a network can transfer.
  • The volume of data that can be transported varies, impacting how effectively a transmission medium, such as an Internet connection, operates.
  • Internet service providers (ISPs) typically denote bandwidth speeds in millions of bits per second (Bps), or megabits (Mbps), and billions of Bps, or gigabits (Gbps).
  • Generally speaking, the higher the bandwidth, the quicker a computer downloads information from the Internet.

Understanding Bandwidth

Bandwidth is a measure of how much information a network, a group of two or more devices that communicate between themselves, can transfer. Data moves from A to B just as water flows through pipes from a supply point to our faucets. The volume that's transported, the bandwidth, varies, impacting how effectively a transmission medium, such as an Internet connection, operates.

Internet service providers (ISPs) typically denote bandwidth speeds in millions of bits per second (Bps), or megabits (Mbps), and billions of Bps, or gigabits (Gbps). Generally speaking, the higher the bandwidth, the quicker a computer downloads information from the Internet, including emails or streamed movies.

The U.S. Federal Communications Commission (FCC) defines broadband Internet speeds as connections with a bandwidth of 25 Mbps for downloads and three Mbps for uploads. Providers state the bandwidth measurement to customers, although the number they quote may not always reflect what a customer actually gets.

The connection could have a bottleneck where one network is limited by the lowest speed going to several computers at once. More computers connected to the same bandwidth speed slow down the bandwidth for everyone who shares the same connection.

Recording Bandwidth

Any computer can measure the amount of bandwidth it actually receives at any given time. Special websites, or the ISP, are able to calculate the bandwidth by sending a file through the connection and then waiting for the information to return.

Bandwidth Requirements

The amount of bandwidth required to surf the web seamlessly depends on the task the user wishes to undertake.

For instance, an instant messaging conversation may use 1,000 bits, or one kilobit, per second in bandwidth. A voice-over conversation, in which someone's voice transmits through computer connections, meanwhile, typically uses 56 kilobits per second (Kbps).

Moving further up the scale, standard-definition video takes one Mbps, while HDX video quality, one of the highest standards on video-sharing services, takes more than seven Mbps for downloading.

History of Bandwidth

Since 1994, the Internet has transformed from a niche technology, serving mainly to interconnect laboratories engaged in government research, to a key part of everyday life. In Dec. 1995, 0.4% of the world's population reportedly had access to the Internet. Fast-forward to June 2019, and over half of the globe is connected.

People now depend on the Internet to communicate, purchase goods, earn an income, gain access to information, and entertain themselves. Over the years, the technology has become more content-heavy, sophisticated, and populated, meaning the amount of bandwidth required to use it effectively has increased substantially.

Fast Fact

In 2019, video accounted for over 60% of the total downstream volume of traffic on the Internet, according to Savine's Global Internet Phenomena Report.

From the end of 2015 to the fourth quarter of 2017, the average Internet speed surged 28.6% to 7.2 Mbps. Ookla, a company that specializes in Internet testing and analysis, claimed that Singapore has the best bandwidth capabilities in the world, with online speeds of 153.85 Mbps—more than double the 75.94 Mbps registered in the United States.

The top countries in the world, and the top states, continue to increase their bandwidths as more users and more devices connect to networks.

Bandwidth demand is expected to continue growing over the next few years. By 2025, the World Economic Forum (WEF) estimates that 463 exabytes of data will be created each day across the globe. Put into perspective, that's the equivalent of more than 212 billion DVDs worth of new data every 24 hours.