Two Types of Speed
This information will help you check your PC’s throughput to and from the Internet. In measuring, there are two categories: upload speed and download speed. If you have a dialup connection, these two rates should be the same. With DSL or cable modems, however, they are probably different, the download speed is faster. This is because your Internet Service Provider (ISP) sells you the service at two different speeds.
Internet speeds are often expressed by different people or programs using different terms. Browsers and file transfer programs often use kilobytes per second, abbreviated “XX KB/Sec””. Your dialup modem and DSL providers probably use kilobits per second. Since it takes 8 bits to make up a byte, you would just divide the kilobit rate to get the equivalent kilobyte rate, right? Well, except for overhead.
The data transferred between your computer and the Internet uses the TCP/IP protocol (Transmission Control Protocol/Internet Protocol). There is some overhead involved because of the control data that must go along with the real data you’re transferring. This overhead can be estimated at around 3%. DSL data uses the ATM protocol, which stands for Asynchronous Transfer Method (not Automated Teller Machine!), adding another 10% overhead. So, with TCP/IP plus ATM overhead, you’re looking at a 13% overhead total.
The bottom line is, to convert your ISP’s advertised bit rate into a byte rate, divide by 8 and then reduce by 13%.
Checking Your Speed
Whew, now that we have our terminology straight, and know how to read the numbers, let’s start checking our rate. The best way to do this is to go to a website that provides this feature. If you perform a search for “check internet speed” on a search engine, you’ll see many sites that freely provide this service. Once you have a site located, follow these guidelines:
- Close down any extraneous programs that are running on your system
- Don’t download other files or use your browser during the speed test
- Try the test both during peak hours (8 am to 6 pm Monday – Friday) and off-peak hours.
- The server you’re testing against may be bogged down. Try other servers (use another testing site) if this seems to be the case (symptoms are if you’re getting slow/no response, or repeated tests show widely different results.)
- Try the speed test several times and average the results (unless the test has several transfers built-in).
- Some speed testing sites offer tips for changing your system settings to improve speed. Some sites will even save your past test results for you so that you can compare it. If you’re so inclined, this procedure can result in a substantial improvement in throughput – Windows, for example, doesn’t come optimized out of the box for DSL or cable modem. Since most of these tweaks involve changing the registry (if you’re running Windows), be sure to back it up first.
It would be very surprising if you find that you have an Internet speed that is near the rate advertised by your ISP. The advertised rates are often laboratory rates – if you can get within 75% – 90% of the advertised rate, that’s pretty good.
In closing, it is often possible to improve your internet speed significantly.
Here are some common causes of slow speeds:
Badly configured PC
Malware, spyware slowing your system down
Packet loss (for example, due to congested network)
Overloading of your ISP’s gateway
The fact that many Internet servers cannot currently offer high speeds to you Peak hour versus off-peak
Hop counts, latency (if you’re a long distance from the destination server)
Stationary Satellite delay (if your ISP is a satellite system)
Poor Upload Speed