BLT is a web-based information system for accessing data measured
by over 300 sensors distributed through the ITLL building. A
variety of computer systems poll the sensors at predetermined
intervals (60 seconds, 300 seconds, 900 seconds, etc.) after
which the data are stored in a central, relational database.
BLT users access the
system through their web browsers. Their browsers trigger
programs to be run on the BLT server machine which retrieve the
requested data from the database, format them and send the
formatted data back to the users' browsers.
The following is a
simplified, graphical representation of the system's data-flow
architecture and a brief description of each of its
components:
- Sensor:
various sorts of measurement apparatus which record physical
conditions in the ITLL building.
- Web
Browser: a standard browser for accessing the world-wide
web.
- BLT
Database: a relational database which holds the data for the
BLT system.
- Data Loading
Applications handle the transfer of data between the
principal data logging computers and the BLT Database.
- Web Server:
a standard server for serving http and ftp requests.
- Data Retrieval
Applications handle requests for BLT data brokered by the Web
Server. The Data Retrieval Applications connect to the BLT
Database, retrieve the requested information, format it and
return the results to the Web Server.The Web Server, in turn,
delivers the information to a user's browser.
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Module
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