E-VLBI Progress with the LBA
Chris Phillips, eVLBI Project ScientistNovember 2011
2
The LBA
ASKAP
Ceduna
ATCA
Parkes
Mopra
Warkworth
Hobart
TidbinbillaYarragadee
Katherine
Existing AARNet DWDM Network
R+E DWDM Network (Under Installation)
Future R+E DWDM Network
3
ASKAP
Ceduna
ATCA
Parkes
Mopra
AUT
Hobart
Tidbinbilla
Network Links
Mount Pleasant (University of Tasmania)
•10 Gbps connection across Bass Strait• Wavelength, not fibre
•Upgraded Mark5a and tested with eVLBI•Tested Mark5B+ for eVLBI compatibility
• University infrastructure does not support jumbo frames, jive5ab (at time of testing) required them
CSIRO. eVLBI Oz 2011
Warkworth
•See Tim’s talk next•1 Gbps link NZ to Australia•eVLBI with DBBC/Mark5b achieved easily in February 2011 @ 512 Mbps
CSIRO. eVLBI Oz 2011
Hartebeesthoek
•First eVLBI test run to LBA on 25 November 2010• Using Mark5a hardware
• Immediate fringes @ 512 Mbps
CSIRO. eVLBI Oz 2011
KVN
•KVN-LBA tests planned for the next few weeks
CSIRO. eVLBI Oz 2011
e-Transport
•All stations except Ceduna using e-Transport of data to a 3rd party data store• Tidbinbilla USB disk shuffle• Using grid-FTP, no certificates
•Most sessions no disk swapping• ATCA 36 TB disk array• Parkes 48 TB disk array
•Typically 100 TB/session•Typically no faster than mail
• Kinder to disks• Lower overhead to staff
CSIRO. eVLBI Oz 2011
Parkes Data Store
•100% COTS solution•4 U chassis with 24 2 TB SATA disks
• SuperMicro •Adaptec hardware RAID card
•ATCA Sun “Thumper”• 28x750 GB
CSIRO. eVLBI Oz 2011
RAID0 5.5 Gbps
RAID5 5.2 Gbps
RAID6 4.1 Gbps
ASKAP VLBI backend
•ASKAP VLBI backend developed at Curtin by PhD student Bruce Stansby
•Based on Signatec PX14400 sampler card• PCI-E x8 card• Dual channel 400 Mbps/14 bit (200 MHz bw)• Lab test dual pol 128 MHz
•Deployed as 64 MHz dual• 4 Gbps recording onto
COTS RAID0
CSIRO. eVLBI Oz 2011
ASKAP eVLBI
• Software conversion to 2 bit with AGC• Requires a few dedicated cores
• Write to network or disk• Short term total power for free
• 4 msec minimum integration time• 10s usec possible easily
• Flexible design• Modified code to realtime spectrometer
• Formats data as LBADR, Mark5B or VDIF• Still limited to 64 MHz bandwidth
• First fringes 27 June 2011 • 128 MHz dual pol should work fine
CSIRO. eVLBI Oz 2011
ATCA image by L Godfrey (Curtin University)
PKS0637-752
Banff SKA Forum e-VLBI demonstration
•Live eVLBI demonstrated during Minister for Science press conference
CSIRO. The high resolution component of ASKAP
DIFX2.0 – Zoom Bands
•DIFX Zoom Bands allows correlation of different bandwidth without resampling• Particular importance with ASKAP with inflexible
sampling system•Use in fringe test in June 2011
• 1x64 MHz at Mopra, 3x16 MHz at other stations• 2x8 MHz zoom bands correlated
CSIRO. eVLBI Oz 2011
AARNet 40 Gbps trials
•AARNet using CSIRO links to telescopes to test roll out of CISCO 40 Gbps technology
•Parkes to ATCA, via Sydney • Deliberately long to showcase technology
•Only requires upgrade of endpoint equipment, long haul infrastructure remains (optical amplifiers etc)
•Current fibres support 80 wavelengths for a total of 3.2Tbps• 8 Tbps using 100 Gbps technology
CSIRO. eVLBI Oz 2011
Contact UsPhone: 1300 363 400 or +61 3 9545 2176
Email: [email protected] Web: www.csiro.au
Thank you
Astronomy and Space ScienceChris Phillipse-VLBI Project Scientist
Phone: 02 93724608Email: [email protected]: www.atnf.csiro.au