What NTRIP stands for

NTRIP — Networked Transport of RTCM via Internet Protocol — is an open standard for sending GNSS correction data over the internet. It was created so that a receiver in the field could pull corrections from a distant reference station using nothing more than a mobile data connection, instead of a radio link to a base station you own.

Almost every modern RTK receiver, including GEO-MEASURE and GEO-PULSE, has an NTRIP client built in. When you “connect to GEODNET”, NTRIP is what is happening under the hood.

Why RTK needs corrections

A standalone GNSS receiver is accurate to a few metres. Signals are delayed by the atmosphere, satellite clocks drift, and orbits are never perfectly known. RTK (Real-Time Kinematic) fixes this by comparing your receiver’s measurements against a reference station at a precisely known location and sending you the difference — the correction — in real time. With corrections applied, accuracy drops from metres to centimetres.

KEY TAKEAWAY

NTRIP is the delivery method; RTK is the correction technique. You need both — a receiver that speaks NTRIP, and a network like GEODNET that generates the corrections.

How NTRIP works

NTRIP has three parts that talk to each other over the internet:

  • NTRIP server — a reference station that generates RTCM correction messages and pushes them to the caster.
  • NTRIP caster — the hub (run by GEODNET) that receives streams from thousands of stations and serves them to users. Each stream is a “mountpoint”.
  • NTRIP client — your receiver or app. It logs in to the caster, picks a mountpoint, and applies the corrections it receives.

GEODNET adds one more step: instead of handing you a single station’s stream, it builds a virtual reference station (VRS) at your position from the nearest stations, so you get a correction tuned to exactly where you are standing.

What you need to connect

  • A GNSS receiver with an NTRIP client (GEO-MEASURE, GEO-PULSE, or any compatible third-party receiver).
  • An internet connection — your phone’s hotspot or the receiver’s own SIM.
  • The GEODNET caster address, port and mountpoint.
  • NTRIP username and password, created when you subscribe to GEODNET RTK.

Setting up NTRIP with GEODNET

  1. Subscribe to GEODNET RTK (monthly or yearly) and create your NTRIP credentials in your account.
  2. Open your receiver’s NTRIP settings and enter the GEODNET caster host and port.
  3. Choose the mountpoint for your region — GEODNET will suggest the nearest one.
  4. Enter your username and password, then connect. A “FIX” status means corrections are being applied.
  5. Check the accuracy readout — you should see horizontal accuracy in the 1–2 cm range within a minute.

Common issues

  • No FIX, only FLOAT — usually poor sky view or a mountpoint too far away. Move clear of buildings and trees and re-check the mountpoint.
  • Authentication failed — credentials are case-sensitive; confirm the subscription is active in your GEODNET account.
  • Corrections drop out — the phone hotspot went to sleep. Keep the screen on or use the receiver’s own SIM.

Frequently asked questions

Is NTRIP free?

The protocol is free and open. The corrections themselves come from a network — GEODNET RTK is $40/month or $400/year, and GEO-MEASURE includes the first year.

Does NTRIP work without a phone signal?

No — NTRIP needs an internet connection. In remote areas, a receiver with its own SIM or a satellite hotspot is the usual answer.

What accuracy can I expect?

With a FIX on the GEODNET network, 1–2 cm horizontal and 2–3 cm vertical is typical.