You can have countless amounts of users on one dedicated DSL, but it's up to you as to who that might be. Just keep in mind that the more users that are on your network, the more the speed will be sacrificed. Cable is based on fiber optic wiring very much like your present cable TV connection. The difference between DSL and cable is that DSL is a line dedicated to one user subscription, and is not shared with a group of other people that happen to live on the same block. You are assigned a particular frequency that only you and your LAN are allowed to use.
Cable is, so to speak, a whole other ball of wax.
Cable is based on fiber optic wiring very much like your present cable TV connection. The difference between DSL and cable is that DSL is a line dedicated to one user subscription, and is not shared with a group of other people that happen to live on the same block. You are assigned a particular frequency that only you and your LAN are allowed to use. The area code and prefix of the phone number at the desired service location and the address of the desired service location are needed to determine availability. The distance between the location and the telephone company Central Office determines service and speed availability.