DSL (Digital Subscriber Line) is a combination of transmission technologies with copper telephone lines as transmission media, including HDSL, SDSL, VDSL, ADSL and RADSL, generally called xDSL. Their main differences are reflected in the difference in signal transmission speed and distance and the difference in the symmetry of uplink rate and downlink rate.

VDSL, ADSL and RADSL belong to asymmetric transmission. VDSL technology is the fastest of the xDSL technologies. On a pair of copper twin-pair telephone lines, the uplink data rates are 13 to 52Mbps and the downlink data rates are 1.5 to 2.3Mbps. But the transmission distance of VDSL is only within a few hundred meters. ADSL supports uplink rates of 640Kbps to 1Mbps and downlink rates of 1Mbps to 8Mbps on a pair of copper wires, with effective transmission distances of 3-5 km. RADSL can provide the same speed range as ADSL, but it can dynamically adjust the user’s access speed according to the quality of twistry-pair copper wire and transmission distance. It is these features that make RADSL an ideal technology for high-speed web surfing, video on demand (IAV), and remote local area network (LAN) access, where users often download much more information than they upload (sending commands).

G. Fast is more advanced than the previous copper wire technologies. It expands the traditional DSL spectrum resources to obtain a larger bandwidth. 106MHz will be used in the initial stage and 212MHz can be extended in the future. Generally speaking, the bandwidth of G. fast can exceed 1 gigabit within 200 meters, which actually refers to the sum of upstream and downstream bandwidth.

The copper wire technology has not stopped on G. fast 1G, and it is expected that the ultra-high bandwidth of above 1G will be realized on the copper wire in the future, which indicates the vitality of the continuous evolution of copper wire to the future. In addition, SENTER is constantly upgrading and optimizing the existing mature VDSL2 and G. Fast tests to greatly improve the performance of long distance and short distance access rate, expand the application scenarios of copper wire and improve the existing copper wire rate. SENTER, as the most advantageous voice and promoter in the copper wire field, has been deepening cooperation with operators to support the national WB strategy.