What is the VSO? (and what isn’t it?)

The VSO …  Allows you to search multiple archives in a single search  Keeps you from needing to keep track of archives  Allows for a consistent interface  Provides data virtualization  Reduces the time spent searching for data  Allows scientists to spend more of their time on science

… allows you to search multiple archives  H-alpha Network  High Altitude Observatory, NCAR  Montana State University  National Solar Observatory  L’Observatoire de Paris  Owens Valley Radio Observatory  Solar Data Analysis Center, NASA  Stanford Helioseismology Archive

… keeps you from needing to keep track of archives  New archives come to you  Don’t need to bookmark dozens of websites

… allows for a consistent interface  One interface, for all archives

… provides data virtualization  Which is just the IT term for those last three slides

… reduces the time spent searching for data  (okay, technically, this is just derived from the others mentioned before)

… allows you to spend more time doing science  (it’s another derived benefit … I was bulking up the list, okay?)

The VSO isn’t …  A file retrieval tool  A specific user interface  A data archive  A single system or server  A file transformation service  Grid computing, or those other current IT buzzwords

… a file retrieval tool  VSO handles finding and ordering data  The browser (UI) does the work, like with other search engines.  Because of the variety in data transfer formats, not all archives provide immediate access Eg. Systems where you request the files, and they you when ready Eg. Systems where you request the files, and they you when ready

… a specific user interface  VSO has a default web based interface  VSO has a published API that allows anyone to write a VSO UI  EGSO and VSPO use VSO to access data  Any program that can download a web page can search using VSO

… a data archive  VSO stores no scientifically useful data products  VSO stores a small description about the holdings of lots of other archives, and uses that information to route requests.

… a single system or server  VSO is a lightweight process, that can be replicated  VSO has no single point of failure  There are currently 3 production instances (SDAC, NSO, SHA)  Future versions of VSO may run as a desktop application

… a file transformation service  Because that’s what CoSEC’s goal is  CoSEC will be able to find data products using VSO

… grid computing  It uses distributed computing, but each part has a specific purpose  Grid computing is useful for CoSEC, though

… some other marketing buzzword  We’re a SOAP WebService, sending XML over HTTP, and have WSDL that describes our API  We’re an OAIS Finding and Ordering Aid

What VSO Does  VSO allows you to find new data products based on search criteria  VSO allows you to order data products from Data Providers.  Anything else is a function of the specific User Interface VSO allows people to write new User Interfaces to build on to the VSO functionality VSO allows people to write new User Interfaces to build on to the VSO functionality

How VSO Works … Finding  The Solar Physicists (or Equivalent), makes a request through a User Interface  The User Interface translates the request into terms that VSO can understand, and sends it to a VSO Instance  The VSO Instance consults its Registry to see which Data Providers may be able to fulfill the request

How VSO Works … Finding  The VSO Instance sends the requests to the Data Providers.  The Data Providers respond back to the VSO Instance  The VSO Instance combines the results, and sends it back to the User Interface  The User Interface formats the results and presents it to the Solar Physicist

Things that can go wrong  The Registry is stale How often do new Data Providers come online? How often do new Data Providers come online?  The Registry can’t find any Data Providers to fulfill the query That means a really quick ‘no records found’ message That means a really quick ‘no records found’ message  A Data Provider doesn’t really have the data they claimed to The Registry can use a different level of granularity to mark that the data sets are not available The Registry can use a different level of granularity to mark that the data sets are not available

Things that can go wrong  A Data Provider isn’t available The VSO Instance will give up, and return what it did get back, and a message about the problem provider The VSO Instance will give up, and return what it did get back, and a message about the problem provider  The VSO Instance isn’t available User Interfaces can fail over to another VSO Instance User Interfaces can fail over to another VSO Instance  Too much data is returned That’s a problem? That’s a problem? Use a more specific query Use a more specific query

How VSO Works … Ordering  The Solar Physicist selects which data products from their searches that they’d like to retrieve in the User Interface  The Solar Physicist specifies how they’d like to obtain the data products  The User Interface sends a request to the VSO Instance

How VSO Works … Ordering  The VSO Instance breaks up the request into parts, and send each part to the correct Data Provider  The Data Providers act upon the requests, and send a response to the VSO  VSO combines the results, and sends it back to the User Interface  The User Interface formats the results and presents it to the Solar Physicist

Things that can go wrong  Need to agree on a data transfer method Can repeat the request until you agree Can repeat the request until you agree  Some Data Providers may require additional information to complete the request Can repeat the request with the needed info Can repeat the request with the needed info

Who is VSO good for?  Solar Physicists who don’t know what data archives are out there or don’t want to know, and only want the data or don’t want to know, and only want the data  Solar Physicists who want to compare data to other instruments than those whose data they normally use Confirming anomalies Confirming anomalies Gap filling Gap filling

Who is VSO not good for?  People who are doing work on specific instruments They know where the data is, and can most likely access it directly They know where the data is, and can most likely access it directly  People looking for desktop pictures to color coordinate with their current ensemble VSO searches for science quality data, although some Data Providers may also provide quicklook images VSO searches for science quality data, although some Data Providers may also provide quicklook images

How can you help?  Use VSO Try it out, so that you can … Try it out, so that you can …  Complain Let us know what you don’t like Let us know what you don’t like  Give Suggestions Let us know what we can do to improve your ability to search for meaningful data Let us know what we can do to improve your ability to search for meaningful data Let us know which data archives are useful to you Let us know which data archives are useful to you