Before NTP became standard in 1988, computers used simpler Time (RFC 868) and Daytime (RFC 867) protocols to sync clocks over networks via port 37, transmitting time as a 32-bit number or human-readable text. These protocols were efficient for 1980s bandwidth constraints but lacked precision, timestamping, and faced a Y2K36 overflow problem; NIST still operates these services today with a custom response format.