Article · Wikipedia archive · Last revised Jun 1, 2026

Networked Transport of RTCM via Internet Protocol

The Networked Transport of RTCM via Internet Protocol (NTRIP) is a protocol for streaming RTCM data over the Internet, commonly used in real-time kinematic positioning. NTRIP is a generic, stateless protocol based on the Hypertext Transfer Protocol (HTTP/1.1) and is enhanced for GNSS data streams.

Last revised
Jun 1, 2026
Read time
≈ 2 min
Length
473 w
Citations
15
Source
Wikipedia ↗
Networked Transport of RTCM via Internet Protocol
Communication protocol
AbbreviationNTRIP
PurposeStreaming of RTCM SC-104 data
Developer(s)Radio Technical Commission for Maritime Services
IntroductionSeptember 2004 (2004-09)
Based onHTTP/1.1; RTSP
Port(s)2101 (TCP/UDP)

The Networked Transport of RTCM via Internet Protocol (NTRIP)1 is a protocol for streaming RTCM data (such as those containing differential GPS (DGPS) corrections) over the Internet, commonly used in real-time kinematic positioning. NTRIP is a generic, stateless protocol based on the Hypertext Transfer Protocol (HTTP/1.1) and is enhanced for GNSS data streams.2

The specification is standardized by the Radio Technical Commission for Maritime Services (RTCM).1 NTRIP was developed by the German Federal Agency for Cartography and Geodesy (BKG)3 and the Dortmund University Department of Computer Science.4 NTRIP was released in September 2004; the initial version was based on HTTP over TCP.5 As of April 2026, the latest version is RTCM 10410.1 Standard for Networked Transport of RTCM via Internet Protocol (Ntrip) Version 2.0 with Amendment 2, January 12, 2021 (US$ 215.00). Version 2.0 can be based on HTTP/1.1 over TCP, HTTP/1.1 over UDP (HTTPU), or Real-Time Streaming Protocol (RTSP).6

Availability

A simplified version of NTRIP 1.0 used to be available for free. It does not have any protocol details or examples, and refers to purchase the document from RTCM.7

RTCM-NTRIP provides open-source (GPL v2) implementations of NTRIP: a minimal client-server pair (ntripclient and ntripserver) and a feature-rich BKG Ntrip Client (BNC).8 The open-source Real-time Kinematic Library (RTKLIB) also implements NTRIP. Under GPLv2, it is legal to reverse-engineer the protocol using the code provided.

Another open-source (Apache License v2) implementation of NTRIP is provided by the Orekit9 space-flight dynamics library10, allowing to parse RTCM correction messages11, RTCM ephemeris messages12 as well as IGS generic SSR messages13.

Service providers

Data from International GNSS Service can be obtained from five providers for free (some of which require registration): BKG, CAS, NASA CDDIS, Geoscience Australia, UCAR. There are site-specific streams containing observation data (for dGPS/RTK) and state-space data (for PPP) as well as combined state-space streams. Multi-GNSS is used.14

References

References

  1. Grauberger, Erik (2025-11-10). "What is NTRIP? RTCM Corrections for GNSS Rovers". Retrieved 2026-01-07.
  2. Lenz, Elmar (2004). "Networked Transport of RTCM via Internet Protocol (NTRIP) – Application and Benefit in Modern Surveying Systems" (PDF). FIG Working Week 2004. Archived (PDF) from the original on 2016-10-27. Retrieved 2018-02-27.
  3. BKG
  4. Uni Dortmund Archived 2012-01-02 at the Wayback Machine
  5. "RTCM Recommended Standards for Networked Transport of RTCM via Internet Protocol (Ntrip), Version 1.0" Archived 2006-10-24 at the Wayback Machine
  6. "RTCM 10410.1 Standard for Networked Transport of RTCM via Internet Protocol (Ntrip) Version 2.0 with Amendment 2, January 12, 2021". Radio Technical Commission for Maritime Services.
  7. It can be downloaded from BKG Archived 2006-10-24 at the Wayback Machine.
  8. software.rtcm-ntrip.org Archived 2020-08-11 at the Wayback Machine
  9. "Orekit library".
  10. "NTRIP stream reading".
  11. "RTCM correction messages".
  12. "RTCM ephemeris messages".
  13. "SSR IGM messages".
  14. "RTS User Access". International GNSS Service.
External links