Introduction to EXPReS - SURFnet and JIVE GigaPort seminar for astronomers T. Charles Yun Program Manager EXPReS Project, JIVE.

Introduction to EXPReS- SURFnet and JIVE GigaPort seminar for astronomers

T. Charles YunProgram Manager EXPReS Project, JIVE

2006 November 02 Tuesday SURFnet/JIVE- Gigaport Astronomy Seminar Slide #: 2

Presentation Overview• Introduction to VLBI• Introduction to EXPReS• Segue into the detailed astronomy and research of EXPReS


GigaPort and SURFnet 6• Without the efforts of SURFnet, e-VLBI would not be possible

in the Netherlands or in Europe• Connectivity between

• Amsterdam and Dwingeloo• Dwingeloo and Groningen

• Leadership• Dedicated light paths as the foundation for SURFnet 6• SURFnet continues to be a leader in the network world


A one slide VLBI primer• A radio telescope looks at an object in the sky and collects data

to create an “image” of the source• Multiple telescopes can view the same object. The distance

between the telescopes is the baseline. The baseline can be compared to building a single telescope with the diameter of this distance (sort of).

• Correlation is the process by which data from multiple telescopes is collected and processed to create a more accurate image. The correlator a super computer (interferometry)

• The resolution of the image increases with the data collection rate. Higher data rates are better; higher resolution is better.

Introduction to VLBI


Once upon a time...• Telescopes collected data on tapes. Tapes were heavy and bulky.

Someone had to stand next to the recorders and change tapes. The boxes had to be boxed and labeled. They were then sent via postal mail to the correlator facility. Once all the tapes arrived from all the locations, you could begin data analysis. Sometimes tapes were lost/damaged. Sometimes data was not recorded properly onto the tapes. It was not unusual for the time between experiment to the beginning of correlation to be multiple weeks.

• Hard drive arrays improved the situation... but only temporarily.

• Today, you can transport the data over the network:

e-VLBI - electronic VLBI



Why transport data over the network?• Using the network to transport data improves science

• Eliminate the need to move physical objects • Real time analysis

• Ability to identify minor problems in data collection • Hybrid observations• Responsiveness to transient events

• Automated observation (hands-off observing)

• Once the data is on the network, there is flexibility to investigate different options (move the correlator, multiple correlators, etc.)



Optical networks, Radio astronomy• Advanced optical networks provide radio astronomy a solution to

the data transport problem.• Networks can address VLBI’s inherently geographically

distributed nature• Assumption: SURFnet will have shown Dutch, European and

international network maps • Network data rates are improving and provide a flexibility not

available with physical media

• VLBI also happens to be loss tolerant, which is a useful characteristic when dealing with high-speed networks

• Layer 2 networking introduces a level of control that allows VLBI to pursue different ways of moving data, thus different ways of obtainin the data for correlations



What is EXPReS?• EXPReS = Express Production Real-time e-VLBI Service

The overall objective of EXPReS is to create a production-level, real-time, “electronic” VLBI (e-VLBI) service, in which the radio telescopes are reliably connected to the central supercomputer at JIVE in the Netherlands, via a high-speed optical-fibre communication network...

- or -

Make e-VLBI routine, reliable and realistic for astronomers

Introduction to EXPReS


EXPReS Details• EXPReS is made possible by the European Commission (DG-

INFSO), Sixth Framework Programme, Contract #026642

• Project Details• Three year, started March 2006• International collaboration• Funded at 3.9 million EUR by the

• Means: high-speed communication networks operating in real-time and connecting some of the largest and most sensitive radio telescopes on the planet



EXPReS Partners• Joint Institute for VLBI in Europe (coordinator), the Netherlands• AARNET Pty Ltd., Australia• ASTRON, the Netherlands• Centro Nacional de Informacion Geografica, Spain• Chalmers Tekniska Hoegskola Aktiebolag, Sweden• Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia• Cornell University, USA• Delivery of Advanced Network Technology to Europe Ltd. (DANTE), UK• Instituto Nazionale di Astrofisica, Italy• Instytut Chemii Bioorganicznej PAN, Poland• Max Planck Gesellschaft zur Foerderung der Wissenschaften e.V., Germany• National Research Foundation, South Africa• Shanghai Astronomical Observatory, Chinese Academy of Sciences, China• SURFNet b.v., The Netherlands• Teknillinen Korkeakoulu, Finland• The University of Manchester, UK• Universidad de Concepcion, Chile• Uniwersytet Mikolaja Kopernika, Poland• Ventspils Augstskola, Latvia



Participating telescope sites

Image courtesy of Dr. Francisco Colomer, <http://www.oan.es/expres/status.htm>



“Heavy Users”• In her introduction, Sandra mentioned “heavy users” of the

network. • Used to be code for physicists at CERN

• Only moving files between two locations• HEP community can be unfairly summarized as FTP • One source, multiple destinations• They are not yet running

• e-VLBI is real-time data transport from multiple locations to the correlator (think: supercomputer), with the ability to capture data at rates that will saturate the backbone of any network

We are doing things today We want more tomorrow

...a quick aside...


Activities in EXPReS• Networking Activities

• NA1: Management of I3• NA2: EVN-NREN Forum • NA3: e-VLBI Science Forum • NA4: e-VLBI Outreach, Dissemination & Communications

• Specific Service Activities• SA1: Production e-VLBI Service • SA2: Network Provision for a Global e-VLBI Array

• Joint Research Activities• JRA1: Future Arrays of Broadband Radio Telescopes on

Internet Computing



The Real work• Today you will hear about from two activities in the EXPReS

Project• JRA1 “FABRIC”• SA1 Production Services

• Each of these activities address different aspects of the effort to take advantage of advanced network technologies in support of e-VLBI

Segue to Astronomy


Questions/Answers• Contact information

T. Charles YunProject ManagerEXPReS (JIVE)tcyun \at\ jive dot nl

• Additional Informationhttp://expres-eu.org/ [note: only one “s”]http://www.jive.nl/

• EXPReS is made possible through the support of the European Commission (DG-INFSO), Sixth Framework Programme, Contract #026642

Conclusion


Do we really need networks?• Fully loaded carrying capacity of a 747 cargo carrying Blu-Ray

DVDs• 37 Tbps

• However• Latency: buy 1,488,800 DVDs (€€), burn each (2 years @ 1

second burn/DVD), hand label (lots of Sharpie pens), box DVDs, transport to airport, load, fly (€€€) time, unload (€), sort boxes, read each DVD...

• Pack Loss: rare, but fairly devastating when you lose “one packet”

• Every transport is unique, no re-use of media.

Source: http://dltj.org/2006/07/internet2-hopi-networkhttp://walt.lishost.org/?p=344

Extra Interesting Bits


How much data does e-VLBI create?• 19 Telescope sites• 1 Gbps data rates• Correlator is currently located in Dwingeloo

• fiber cross-section is into the correlator is non-trivial• e-VLBI science runs can last for arbitrarily long periods of time,

but 3 weeks runs are not unusual

• 19 sites x 1 day x 512 Mbps= 19 sites x 86400 seconds x 512 Mbps= 840,499,200 Mbits= ~105 TeraBytes per day

Conclusion


Networking activities• NA1: Management of I3

• Provides resources to effectively manage the EXPReS I3 project. The objective is to efficiently manage EXPRES and monitor the overall progress of the project goals, in particular the realisation of a production-level e-VLBI infrastructure. Responsible for the overall financial management of the project and the generation of annual and final reports via input from the chairs of the NA, SA and JRAs.

• NA2: EVN-NREN Forum • Partially supports a forum in which representatives of the networking and radio astronomy technical community will meet

and interact with each other, including day-to-day communication via the on-line EVN-NREN email forum. The objective is to ensure that both communities are effectively engaged and that together they agree and move forward on the solutions, objectives and development priorities within EXPReS.

• NA3: e-VLBI Science Forum • Partially support the activities of the e-VLBI Science Advisory Group (eVSAG). The objectives of this activity will be to

ensure that e-VLBI end-users are well informed and organised about EXPReS developments and can provide critical review of the project’s evolution. This group will also help promote & develop the full potential of the e-VLBI technique as an astronomical application.

• NA4: e-VLBI Outreach, Dissemination & Communications • Partially supports outreach and communication aspects of the EXPReS I3. Objectives include: creation of the EXPReS

web-site (addressing public outreach, project management and end-user communication requirements), general promotion of EXPReS to the broad scientific and networking communities via a programme of PR activities.

General Notes and Information


Specific Service & Research Activities• SA1: Production e-VLBI Service

• A programme of integration and development that will provide astronomers (and other end-users) with a production level e-VLBI infrastructure service, capable of servicing and robustly processing e-VLBI data streams of up to 16 Gbps (net) at the EVN data processor at JIVE. The objectives will be to realise a distributed scientific instrument with unique capabilities - an e-VLBI infrastructure operating in real-time - a service that will be expandable to include input from up to 16 telescopes located across the planet (including individual telescopes of the UK e-MERLIN array).

• SA2: Network Provision for a Global e-VLBI Array • A programme of network communication provision that will permit radio telescopes across Europe and the rest of the

world to obtain last mile connections to high-speed communication networks that can be connected to national research networks and international communication networks, in particular GÉANT.

• JRA1: Future Arrays of Broadband Radio Telescopes on Internet Computing

• A research project that looks towards the future hardware and software requirements that will enable the development of an e-VLBI facility in which data flows of ~ 10-30 Gbps per telescope can be reliably sustained and processed. The main objectives are to design and prototype an e-VLBI data acquisition platform (based on COTS hardware), investigate transport mechanisms and identify protocols that are optimal for e-VLBI, develop a software correlator (e-VLBI data processor) that can run on standard workstations and take advantage of distributed Grid computing resources.

General Notes and Information

Introduction to EXPReS - SURFnet and JIVE GigaPort seminar for astronomers T. Charles Yun Program Manager EXPReS Project, JIVE.

Documents

vlbi slide

transport data

slide vlbi primer

electronic vlbi introduction

expres surfnet

data analysis

expres details expres

research of expres slide