DSL has two types, ADSL and SDSL. ADSL is primarily what residential clients receive. It is suitable for basic internet needs like email and web surfing. Data transmissions can be secured via IPSec tunnel. DSL is not suitable for video download or VOIP because of its low upstream. DSL generally is less expensive than cable. SDSL is what business can receive as it is suitable for VOIP because of its symmetrical and higher bandwidth. Either type of DSL is generally available where broadband is not because it run on different lines at the street than broadband runs. DSL uses analog lines at the street whereas cable uses cable or fiber at the street. Cable is suitable for VOIP and video chat because of its higher upstream, up to 1.5MBps. It is also suitable for other data transmission which can be secured over and IPSec tunnel. There is a rule of thumb between ISP providers over the space on the telephone poles that ISP providers do not cross boundaries with each other which is why one will never be able to have a choice between AT&T (DSL) or Comcast (Cable).