出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：An important outcome of the 7th International e-VLBI Workshop in Shanghai in June 2008 was
the creation of a task force to study and recommend a universal VLBI data format that is
suitable for both on-the-wire e-VLBI data transfer, as well as direct disk storage. This task
force, called the VLBI Data Interchange Format (VDIF) Task Force, is the first part of a two
part effort, the second of which will address standardization of e-VLBI data-transmissionprotocols.
The formation of the VDIF Task Force was prompted by increased e-VLBI activity
and the difficulties encountered when data arrive at a correlator in different formats from
various instruments in various parts of the world. The task force has proposed a streaming
packetized data format that may be used for real-time and non-real-time e-VLBI, as well as
direct disk storage. The data may contain multiple channels of time-sampled data with an
arbitrary number of channels, arbitrary #bits/sample up to 32, 'real' or 'complex' data; data rates
in excess of 100Gbps are supported. Each data packet is completely self-identifying via a short
header, and data may be decoded without reference to any external information. The VDIF draft
proposal, with a few minor modifications, was formally accepted at the 8th International e-
VLBI Workshop in Madrid in June 2009, and work has already begun by several groups to
implement software and hardware support for the VDIF specification.
