The Networked Transport of RTCM via Internet Protocol (NTRIP) is a protocol for streaming differential GPS (DGPS) corrections over the Internet for real-time kinematic positioning.
[1] The specification is standardized by the Radio Technical Commission for Maritime Services (RTCM).
[2] NTRIP was developed by the German Federal Agency for Cartography and Geodesy (BKG)[3] and the Dortmund University Department of Computer Science.
[6] NTRIP used to be[7] an open standard protocol but it is not available freely (as of 2020).
There is an open source implementation available from software.rtcm-ntrip.org from where the protocol can be reverse-engineered.