The SFDU Science Data User's Workbench - Integrating Data Across Continents and Cable TV Networks

Frank LoPinto
Computer Sciences Corporation
10000A Aerospace Road
Lanham, Maryland 20706
(301) 794-1486
LoPinto@niccolo.gsfc.nasa.gov

Kaveh Habibelahy
Computer Sciences Corporation
10000A Aerospace Road
Lanham, Maryland 20706
(301) 794-1871
kaveh@niccolo.gsfc.nasa.gov

Mark Hei
Computer Sciences Corporation
10000A Aerospace Road
Lanham, Maryland 20706
(301) 794-1802
hei@niccolo.gsfc.nasa.gov

Payter Versteegen
Computer Sciences Corporation
10000A Aerospace Road
Lanham, Maryland 20706
(301) 794-1767
payter@niccolo.gsfc.nasa.gov

Steve Smith
Logica UK Limited
ESA/ESOC
Robert Bosche Str 5,
D-64293 Darmstadt, Germany
+49 6151 902 816
stsmith@esoc.esa.de

The SFDU Science Data User's Workbench is a tool for handling
Standard Formatted Data Units. It was developed at NASA Goddard Space
Flight Center to illustrate the benefits of packaging data in SFDUs.  The
SFDU concept was developed by Panel 2 of the Consultative Committee on
Space Data Systems (CCSDS) of which NASA is an active member.

The Workbench was developed to illustrate the benefits of packaging data
in SFDUs. It is engineered as an organization of autonomous objects which
communicate over a network. We use a simple message routing system, called
a Switcher, which accepts TCP/IP connections from other objects, registers
their names, and routes messages among them.  This has the effect of
implementing a mesh network at the application layer on top of a star
network at the session layer (of the ISO stack).

When a Workbench object is initialized, it reads a configuration file to
get the TCP/IP address of a Switcher.  By connecting to the Switcher, the
object joins a distributed system.  A Workbench can contain one or more
Media Objects.  These provide an abstraction of files and filesystems using
CCSDS naming conventions.  Media Objects can be installed anywhere on the
Internet thereby allowing a Workbench user to access multiple and distributed
datasets.

We will demonstrate a configuration in which a Workbench at the meeting site
is used to create an SFDU from files having different formats and stored at
different locations.  One Media Object will run on a Unix server that is
located at the European Space Agency in Germany and connected to the Internet.
Another will run on a Linux server located in Anne Arundel County, Maryland.
This server is connected to the Internet using a pair of Cable TV channels
as part of a cooperative agreement with NASA intended to prove the feasibility
of providing high speed Internet access to the general public.