IVOA Data Access Layer: Goals, Achievements and Current Trends
  The IVOA Data Access Layer (DAL) working group was created in 2002 to define protocols to homogenize data discovery, data description, data retrieval, and data access processes. We describe its history and status today, and look at current trends for future development of the DAL protocols. 
Fran\c{c}ois Bonnarel, Patrick Dowler (CADC), Keith Noddle (IFA),   Douglas Tody (NRAO)
astro-ph.IM