VSI-E = VSI (VLBI Stanard Interface) specification
for Network data transfer

VSI-E specification is a standard specification of network data transfer prococol for VLBI data. There are standard specifications for VLBI equipment for Hardware VSI-H and for software (control) VSI-S. The specification of VLBI Standard Interface (VSI) is authorized by International VLBI Service (IVS) and it is proposed under the collaboration with Haystack Observatory.
However the VSI-E is comprehensive and its software suite (C++ class library) is well designed, VSI-E itself was not widely delopied in the world VLBI community. Only VOA-200 (VLBI Optical Adapter) developed by Prof. Kawaguchi of NAOJ for VLBI data transfer has employed the VSI-E and it enabled 8Gbps realtime data transfer from VLBI data sources.

Note: The idea of VLBI Standards of e-VLBI has been realized by VDIF (VLBI Data Interchange Format) and VTP (VDIF Transport Protocol) in 2009.

VDIF = VLBI Data Interchange Format Specification

In the 7th eVLBI workshop held at Shanghai in 2008, necessity of international common data format specification has was intensively discussed. Consequently VLBI task forece to make a proposal of common data format has placed. Alan Whitney(MIT), Mark Kettenis(JIVE), Chris Phillips(ATNF) and Mamoru Sekido(NICT) have discussed the specification mainly by e-mail conversation. That common format is named VDIF (VLBI Data Interchange Format) The first version of VDIF specification has been ratified in the e-VLBI workshop heldt at Madrid in 2009. VDIF allows extension version for the usage of extended header area. NICT's extension version is also available from the same web page.

VTP = VDIF Transport Protocol Specification

As a transport protocol of VDIF over the network has been also discussed and the first version of VDIF Transport Protocol (VTP) is accepted in the Task Force.