NASA will be performing maintenance on Wednesday, June 5 from 9:00am - 11:00am EDT (1400 UTC - 1600 UTC). You may experience difficulties accessing the NTRIP real-time data streams. You may experience multiple short (several minute) intermittent outages during the maintenance window. Existing connections will need to be restarted. If you experience problems outside this window, contact

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Real-time data

The CDDIS has real-time streaming software (NTRIP, Networked Transport of RTCM via Internet Protocol) for receipt and transmission of real-time GNSS data and product streams in support of the IGS Real Time Service. The available product streams consist of GNSS orbit and clock corrections, which enable various applications such as precise point positioning (PPP).

The intention of the CDDIS NTRIP caster is to disseminate Broadcast Corrections for GNSS satellite orbits and clocks in real time in RTCMv3 format. Details about GNSS product streams are available through the caster's Source table. Information on connecting to the CDDIS Caster, streams that we carry, and client configuration is available.


The CDDIS real-time data caster is provided freely to all users. The IGS RTS and the CDDIS make no assurances, implied or otherwise, for the accuracy or availability of the Service. The Service can have outages and degradations in accuracy and these events can render the Service unsuitable for any use. The Subscriber shall indemnify, defend and hold the CDDIS and its affiliates harmless from any loss or damage resulting from any claim by any person relating to the data services provided through the Service. The user will be required to acknowledge these terms of service when registering for the Service.

System Access

All of the product streams on this NTRIP caster are protected. Authorization is a two step process:

1. Register for an Earthdata Login account: registration with our NASA colleagues at EOSDIS.

2. Complete the CDDIS registration form found here.

System Status

Detailed information on system status, including current stream status and latencies (current and past 24 hours) are available.

Map depicting locations of sites with real-time data streams available through CDDIS Map depicting latencies of sites with real-time data streams available through CDDIS
Map depicting latencies of sites with real-time data streams available through CDDIS Sample box plot of latency distributions

Client Software Information

Real-time data streams from the CDDIS-NTRIP system can be accessed from a variety of clients, including ready-to-use graphic user interfaces, command-line applications and user-built custom software. More information can be found here.

For all NTRIP client connections you will need the following information:

  • NTRIP Casters Address:
  • Port: 443
  • User ID: <Your Earthdata Login username>
  • Password: <Your EarthData Login Password>
  • MountPoint: Desired stream (status of streams can be found here)

Contact Information

Contact the help email address if you have any other questions.