W32Time is an implementation of Simple Network Time Protocol (SNTP), described in Informational RFC 1769. SNTP is an adaptation of the Network Time Protocol (NTP) described in Standard RFC 1305.

[Michael Brutman] decided to mix today’s world of network time synchronization with the old world of batteryless PCs, and built an SNTP Time Server that runs on a DOS PC.

[Derek]’s project is called the SNTP clock. As you might expect, it gets its name from the protocol used to automatically synchronize the clock in your computer with other network time servers.

Unlike SNTP (simple network time protocol), the time when data is transmitted does not need to be transmitted in the synchronization packet, itself, but in a following packet.