You may have noticed different Internet plans have different prices, and the difference between the packages is the speed. But they may not explain it. So what is Internet speed? Read on.
First, a note about data and memory
Computer memory is measured in bits and bytes. A bit is the smallest unit of memory. A byte is the amount of memory one character on this screen consumes. With overhead, one character needs 10 bits to transmit. For the sake of this discussion, at least. Data is measured in bytes, kilobytes, megabytes and gigabytes. To convert it to bits, multiply it by 10.
That helps you put network speed in context, at least. It helps to understand what you can do with what you’re measuring.
How Internet speed is measured
Network speeds today are measured in megabits per second. That’s how many millions of bits they can transmit per second. So that’s a measure of how much data they can transmit in a second. An Internet connection of 10 megabits could transmit a million characters in a second. So it can transmit a lot of text in a hurry.
I’m dating myself here, but the first time I went online, I used a modem that transferred 300 bits per second. Each line came on the screen about the speed I could read it. It was slower than a 1980s dot matrix printer. That was around 1986. It was novel, and a glimpse of the future. It was exciting, but it really wasn’t very practical.
We don’t just transmit text these days. We transmit graphics, audio and video. Of the three, video is the most demanding. It’s also a major thing people use their Internet connections to do today. That fuels demand for ever faster Internet speeds.
The data transmits in both directions. Downlink speed measures how quickly you can download, or receive data. Uplink speed measures how quickly you can upload data. The two speeds don’t have to be equal, and often aren’t. Uplink speed is often lower. That means I can download a photograph from my e-mail much faster than I can upload it to the drugstore to have a print made. Since most people download a lot more than they upload, this usually isn’t a big issue.
How much Internet speed do you need today?
For one person to stream HD video, you need about 5 megabits downstream. It scales linearly. For a family of four to watch four different things at a time, you’d need 20 megabits down. For 4K video, the requirements balloon to 25 megabits downstream per stream. So for a family of four to watch 4K, you’d need a 100 megabit connection.
You always want to leave some extra. It’s pretty rare these days to just watch video. And your computers may very well be running things in the background that require some bandwidth.
Prior to 2015, the FCC defined a 4-megabit connection as high speed. That’s not enough to stream video, so that definition was clearly obsolete. Today the FCC defines it at 25 megabits. I still think that’s low. It’s not hard for a family to chew through 25 megabits.
So what is Internet speed?
Internet speed is nothing but a measure of how fast your Internet connection can pump data. Hopefully, when you get that flyer in the mail or that phone call pitching Internet service, now you have a better understanding of what they’re selling you and what you can do with it.
David Farquhar is a computer security professional, entrepreneur, and author. He started his career as a part-time computer technician in 1994, worked his way up to system administrator by 1997, and has specialized in vulnerability management since 2013. He invests in real estate on the side and his hobbies include O gauge trains, baseball cards, and retro computers and video games. A University of Missouri graduate, he holds CISSP and Security+ certifications. He lives in St. Louis with his family.