At the least, disable file and printer sharing if they are not needed. That is beyond the scope of this article. It would be reasonable to expect that as many as 500-2,000 people would be sharing your cable segment. Since downstream rates are affected by so many factors, it is hard to give an accurate number that you could expect to obtain. Expect a minimum of at least a few hundred kilobits per second.
Many users can obtain over one megabit per second at times.
The cable access box and the Ethernet card are both designed for 10-megabits per second. It would be unreasonable to expect these components to deliver three times greater than their designed performance. The minimum performance for DSL is four to five times higher than a V.90 modem. The normal voice telephone line is unchanged. The data line goes to a DSL box that is connected to a 10-megabit Ethernet adapter in the computer.