Welcome to the VLBI standards website.

The intention of this site is to bring together the currently active VLBI standards at a single reference site. The current standards that are covered are:

VLBI Experiment Definition (VEX) - a framework for defining the setup details and schedule for a VLBI experiment. First defined in 1995, VEX has been widely adopted by the geodetic-VLBI community, and is more recently being adopted by the global astronomical-VLBI community as well. Efforts are now (2010) underway to extend VEX, called 'VEX2' to properly support new VLBI equipment and more complex experiments.

VLBI Standard Interface (VSI) - ratified in 2000 as a standard electrical/timing (VSI-H) and supporting software (VSI-S) specification; VSI has now been adopted in a number of various pieces of VLBI equipment developed at various institutions worldwide.

VDIF Transport Protocol (VTP) - VTP defines how VDIF data should be streamed over standard network connections such as Ethernet.

VLBI Data Interchange Format (VDIF) - ratified in 2009 as a standardized VLBI raw-data format that is compatible with both recording systems and network transmission. VDIF is increasingly being adopted by the VLBI community.

VLBI File-Naming Conventions - in order to facilitate global VLBI data transfers, a file-naming convention for VLBI raw-data files was adopted in 2009.

VLBI On-line Technical Documentation - links to known VLBI Technical information at institutes around the globe. Please contact the site administrator if you have links to information that should be added.

VLBI Support Forums - VLBI community forums to discuss technical issues. Current forums are Mark5, Mark6, and RDBE. Requests for setting up additional forums are welcome.

Please send comments, suggestions, requests to:
VLBI-admin at haystack(dot)mit(dot)edu