Measuring Speed

How Is Internet Speed Measured?

Computers are designed to befuddle; that's the obvious conclusion when you discover that even computer gurus sometimes get confused when trying to measure the speed of their Internet connection.

Actually, there are just a few common points of confusion about measuring Internet speed, ones that any Time Warner Cable Modem subscriber can understand. With these under your belt—and a few tips about how to accurately measure the speed of your Internet connection—you'll be able to determine just how fast Time Warner Cable Modem is compared to other Internet services.

Internet Speed Is Measured In Bits-Per-Second
In fact, the speed of any form of communication between your computer and another device—a dial-up modem, parallel port, or network card—is also measured in terms of bits-per-second; this is the standard for describing the speed of computer communications.

While it may seem confusing at first, this standard is based on common sense. Many forms of digital communication are "serial", meaning that bits are sent through a wire one at a time. It's not surprising you'd measure the speed of these connections in terms of how many bits were sent each second. The other reason this makes sense is that the number of bits needed to transmit the smallest usable chunk of data—a byte—can vary from 7 to 12 depending on how it is transmitted.

For these reasons, measuring communications speed in bits-per-second can actually be helpful, allowing you to compare the raw communications speed of different technologies. In this way, you can tell that a 14.4 kbps (kilobits-per-second) modem is about 50 times faster than a 300 bps (bits-per-second) modem. At 7 Mbps (Megabits-per-second), a Time Warner Cable modem is about 170 times faster than the average speeds you'll see from a dial-up modem.

Web Browsers Measure In Bytes-Per-Second
Web pages are made up of computer files, each of which stores text or a graphic image. To display a web page, your web browser (Internet Explorer or Netscape Navigator, in most cases) downloads these files and stores them temporarily on your hard disk.

As with most forms of storage on your computer, the capacity of files is measured in terms of bytes. Therefore, if you download a file with your web browser, it almost always reports the average speed of the download in terms of bytes-per-second or, more commonly, kilobytes-per-second.

Right away, you can start to see a source of confusion for many people: the speed of your dial-up, ADSL, or cable modem is listed in terms of bits-per-second, but your browser reports speed of downloads in bytes-per-second. Pretty confusing as it is, but it gets worse.

To B Or Not To b: It Matters
Unfortunately, web browsers—and many other Internet software applications—don't actually use the term "kilobytes-per-second" to report the speed of a download, they use its abbreviation: "kBps." Note the similarity to the abbreviation for kilobits-per-second—"kbps"—and the great opportunity for confusion.

As you've gathered, the uppercase "B" means bytes, the lowercase "b" means bits. This is not a small difference, since a 100 kBps download is eight times faster than a 100 kbps download, yet it is easy to overlook.

And just to confound things even more, it's not unusual to see an uppercase "K" used in abbreviations for speed—as in KBps—even though the case of the "K" doesn't mean anything. It's especially common to see speeds described this way in marketing materials; hence, 56 kilobits-per-second modems were known first as "56 kbps modems" and finally just as "56K modems".

How Do We Get Out Of This Mess?
As a rule, always measure the speed of the Internet in terms of bits-per-second. If you see a speed listed in terms of bytes-per-second (or using an abbreviation with an uppercase "B"), multiply this number by 8 to convert to bits-per-second. If your browser reports a file downloaded at 150 KBps, you'll know this is 1200 kbps, or about 1.2 Mbps—a respectable speed by any standard.

If you really want to be precise, however, nothing beats the do-it-yourself approach:

1. Grab a watch with a second hand.
2. Find a big file on the Internet you haven't downloaded before.
3. Time how long it takes to download the file.
4. Take a look at the file on your hard disk and see how large it is (in Megabytes or MB).
5. Multiply the file's size by eight to convert it to Megabits (or Mb).
6. Divide the result from step 5 by the number of seconds it took to download the file, yielding an average download speed in Megabits-per-second (or Mbps).
7. Multiply the result from step 6 by 1.1 to compensate for overhead added by various Internet protocols.
8. If you want to convert this speed to kilobits-per-second (kbps), you can do so by multiplying the result from step 7 by 1024.

Standard Time Warner Cable Charlotte cable modem speed capable of 7 Mbps maximum download by 384 kbps maximum upload. As a rule of thumb, when using the standard cable modem package a speed between 0.5 and 3.1 Mbps is typical when downloading files from the public Internet. If your speed is between 1.1 Mbps and 6.5 Mbps, you are doing great. Anything above 1.2 Mbps is nothing but luck when on the public Internet since many servers are only connected with T1 or T3 lines.

Before making a conclusion about whether the speed you receive from a particular download represents a problem with Time Warner Cable Modem, it's important to understand the factors that can affect Internet speed. You should typically download eight or ten large files from different Web sites; the fastest of these downloads will indicate the minimum speed provided at that time.

Testing your Speed

Several files are available for download on the Road Runner Web site which can be used to test speeds. In addition, a regional speed tests is available from the Time Warner Cable office in Raleigh, North Carolina. Click here to try the speed test on your computer.