It is wise to check if your Internet speed is what you have paid for. Cable service, such as TimeWarner’s Roadrunner, lets you know the speed your Internet is at; however, did you know that Cable internet service is a shared service? This means if many people in your apartment building have the same Cable service, you will be sharing the bandwidth or speed especially when everyone comes home from work, possibly lowering your current Internet speed. Sometimes, the cable company takes advantage of this shared service offering at your expense.
DSL, on the other hand, is a fixed, direct service, and not shared like cable. So, for DSL, there should be no exceptions for not receiving the internet speed you’re paying for.
Other than the Internet providers trying to stretch their dollars, your Internet speed may be slow due to a failing Internet modem, router, or infected computer.
To test your Internet speed, for your home computer network or office network, you may go to the following speed test 
sites below:
Bandwidth Place – A quick one-click button to test your Internet speed
CNET Bandwidth Test – A more detailed test that provides alternate faster Internet providers.