Description of the Virtual Observatory architecture, and IVOA documents that make it explicit. Part of the virtual observatory course by Juan de Dios Santander Vela, as imparted for the MTAF (Métodos y Técnicas Avanzadas en Física, Advanced Methods and Techniques in Physics) Master at the University of Granada (UGR).

1. VO Architecture Documents
Juan de Dios Santander Vela (IAA-CSIC)

2. Overview
The Virtual Observatory: Layers & Architecture
VO Elements
VO Resources

3. VO Architecture

4. VO Architecture
User
Views
(Apps, Web Portals…)
Services
Registry
(Data, Computing…)
VO Infrastructure

5. VO Architecture

6. VO Architecture

7. VO Architecture
User
Views
(Apps, Web Portals…)
Services
Registry
(Data, Computing…)
VO Infrastructure

8. VO Architecture
Access
Service kind
protocol
OAI-PMH Registry servers
VO Web Services
VO App Local file
storage
<interacts SIAP Image servers
User with>
VO App
SSAP Spectra servers
Web Browser in VO
Portal SCS Catalogue servers
User's Machine Traditional web
HTTP
servers
Internet
PLASTIC/SAMP messages
Local file access
VO data access protocols (Data Access Layer),
and other web services' access protocols

9. VO Architecture

10. VO Architecture

11. VO Architecture

12. VO Architecture

13. VO Architecture

14. VO Architecture

15. Resource Registry
Resource
Resource
Identifier
Metadata
(IVO)
VO
Resource
Registry VOData Standard Application
Interface Service RegExt RegExt
SimpleDAL
RegExt

16. VO API
VO Application
Data Model Mapping
(SIAP, SSAP, SCS)
SOAP: OAI-PMH
PLASTIC, SAMP
Spectral Energy
DAL protocols
Distribution
XML-RPC:
VOTABLE
(Registry)
REST:
FITS Manipulation
Other application-specific APIs (cfitsio, nom.tam.fits,
PyFITS…)
Web-Services API
XML Manipulation
(SAX, EXPAT, DOM…)
Operating System Services
VO-specific API

17. VO API
get coordinates
for object name
get info
for object
show object
coordinates
obtain data
available for
object in suitable
services obtain relevant services
given coordinates and
other selection criteria
query relevant services
fulfilling criteria
display retrieved data
in suitable form

23. VO API
get coordinates
for object name
WEB SERVICES
get info
for object
show object
coordinates
obtain data
available for
object in suitable
services obtain relevant services
given coordinates and
other selection criteria
query relevant services
fulfilling criteria
display retrieved data
in suitable form

24. References & Links
IVOA Architecture (IVOA Note 2010-11-23)
Integrating Radio Astronomical Archives and
Legacy Tools in the VO Framework, Ph.D. Thesis,
Chapter 2