Mark 6 next-generation disk-based VLBI data recording system

Mark 6 VLBI Data Recording System

The Mark 6 system, developed by Haystack Observatory, is a 16 Gbps next-generation disk-based VLBI data recording system based on high-performance commercial off-the-shelf (COTS) hardware and open-source software.

See also the Haystack Mark 6 Memo Series.

Mark 6 system characteristics:

  • Four 10GigE input ports
  • 16Gbps sustained record capability
  • Supports up to four 8-disk modules for recording/playback
  • Based on inexpensive high-performance COTS hardware
  • Easily upgradeable hardware on Moore’s Law curve
  • Linux OS (Debian Squeeze 6.0.3 and CentOS 7)
  • Supports all common VLBI data formats
  • Haystack-supported fully open-source software (C and Python)—see below
  • VSI-S and XML command set support
  • Scatter/gather file system to manage slow and/or failed disks
  • Playback support on DiFX correlator for VDIF and Mark 5B data formats
  • Smooth transition from Mark 5
  • Preserve as much investment in existing Mark 5 systems as possible
  • Existing Mark 5 SATA disk modules easily upgradeable to Mark 6
  • Extensive stress testing in real-world operational environment

Mark 6 availability:

  • Purchase full Mark 6 16Gbps system from Conduant Corp
  • SSD OS disk available as option
  • Upgrade your existing Mark 5 system to Mark 6
  • Purchase Mark 6 disk modules (with or without disks)
  • Upgrade existing Mark 5 SATA modules with upgrade kit from Conduant
  • Contact greg@conduant.com for quotes

Coming in near future:

  • Playback as standard Linux files using FUSE interface
  • e-VLBI data-transfer support

In order to preserve as much investment as possible in existing Mark 5 systems and disk modules, Haystack Observatory is collaborating with Conduant Corporation in the design of the Mark 6 chassis and modules; all software has been developed by Haystack Observatory. Existing Mark 5 SATA modules are upgradeable to Mark 6 compatibility with an upgrade kit consisting of a new module backplane with a new high-reliability power connector at the rear and a new front panel with connections for two SAS2 data cables. and front panel; Mark 6 systems use the same bare chassis as Mark 5, and existing Mark 5 chassis are upgradeable to Mark 6 compatibility by replacing all electronic components.

Prototype Mark 6 systems are routinely in use for VGOS development work using the Westford Observatory and NASA/GGAO Observatory.

Haystack Observatory also gratefully acknowledges the continuing support of the NASA/GSFC High-End Network Computing Group for consultation on high-performance COTS hardware that have greatly helped in the development of Mark 6.

Mark 6 documentation

Mark 6 software