We wanted to create an environment which would have the following
- Specify problems in science language, not in shell instructions.
Provide Advanced Track (extended control) and User Track (take defaults
from the black box).
- Hierarchy of contexts: User -> Problem -> Session
- Problem -- scientific requirements for some calculations
- Session -- particular run
- Application -- computational component (applications could be
chained to create multi-step computation scenario. Glue needed
to connect different software packages).
- Transform scientific requirements to specific software and hardware
- Pay attention to the security, authentication, and accounting (DoD)
- We assumed that jobs submission and resource discovery will be done
eventually by computational grid, so rather than devise some sophisticated
authentication schemes we were using a simple model for testing (ssh)
knowing that it will be eventually replaced with some generally
accepted service (e.g., GIS of Globus).
- Provide hooks for collaborative environments, searching, journaling,
indexing. Users have profiles (in XML) and hierarchical directory
tree with XML files describing actions and results.
- If you want people to use this thing, it needs to offer advantages
to working/login directly with shell.
- Make it extensible, so adding new tools and analysis modules is easy.
Use Object Oriented approach (Java) and use XML files (and corresponding
DTDs -- the XML Schemas/XSD or Resource Description Framework/RDF
was not there yet) to describe actions, results,
necessary parameters, available resources, etc.
This would allow using commodity components, and allow to describe
functionality and requirements of software packages. If this had
reached the community level participation, we would have a way to
describe and annotate the computational tasks.