DSL
Digital Subscriber Line
A broadband technology that carries data over ordinary copper telephone lines.
DSL delivers internet connectivity over existing twisted-pair phone wiring, separating voice and data onto different frequency bands so both can share the line. Variants such as ADSL offer faster download than upload speeds, and throughput drops as distance from the provider equipment grows. From a security view it is a wide-area access link whose customer premises modem and router should be hardened, kept patched, and stripped of default credentials. It is a legacy last-mile technology that contrasts with fiber and cable broadband.
Looking DSL up is step one. Getting tested on it is step two.
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