Which of the following WAN technologies has the highest latency?

POTS (Plain Old Telephone Service) dial-up connections are slow in bandwidth but have terrestrial latency measured in tens of milliseconds, far lower than satellite.

Cable internet uses terrestrial coaxial infrastructure with latency typically under 20 ms, which is much lower than satellite.

Geostationary satellites orbit approximately 35,786 km above Earth. A signal must travel from the sender to the satellite and back down to the destination, resulting in a one-way propagation delay of roughly 250 ms and a round-trip latency of 500-600 ms - far exceeding any terrestrial WAN technology.

DSL uses existing copper telephone lines with terrestrial latency typically under 30 ms, which is much lower than satellite.