Telkom is the only supplier of ADSL lines. Even if you get your line rental done through an ISP, they still have to do it through Telokm. It's all Telkom infrastructure.
You have to take an analog voice line rental as a base to having an ADSL line rental. Why? Because Telkom is a monopoly and they say so. There is no technical reason why (although they will argue they have to recover cost on maintenance).
