US Government security requirements no longer permit CDDIS to offer data via traditional unencrypted anonymous ftp; this service was discontinued on October 31, 2020. All data are still available, however access must be via HTTPS or ftp-ssl.

Instructions with examples and our FAQ can be found at:

If you still have difficulty after reading and attempting the examples on that page, please contact us at

close window
Data and derived products overview

The CDDIS archives and distributes mainly Global Navigation Satellite System (GNSS), laser ranging (both to artificial satellites, SLR, and the moon, LLR, Very Long Baseline Interferometry (VLBI), and Doppler Orbitography and Radio-positioning Integrated by Satellite (DORIS) data for an ever increasing user community of geophysicists. CDDIS data and derived products are accessible at and via other methods.

GNSS antenna
NGSLR site at GGAO
VLBI2010 antenna
DORIS antenna