Cable modem and DSL technologies for broadband Internet access are slow to mature and will take a long time to outgrow technical and provisioning problems. Telcos and cable providers have had to upgrade equipment, installing DSL access multiplexers in the former case and moving to two-way-capable, 750MHz hybrid-fiber-coaxial networks in the latter. Each group markets its service by attacking the other's technology; both have serious limitations. ADSL, the most widely deployed version of DSL, requires customers to be located less than 18,000 feet from the central office and is not compatible