There are two repositories in CAD - the LDAP which is synchronized from ICM for config data, and has CAD specific data as well; and the agent RASS database holding 7 days of info that rolls along. Neither of these are useful to you.
The UCCE schema - in particular, the real time tables on the AW - is what you need. This is on CCO.
We have done wallboards this way - but you must think about how this shall be done in the most efficient way.
You need a central server that makes the fastest possible SQL query on the relevant AW table and drops the results into memory. All calculations must be done by this server in memory.
It also acts as a distributor to the real wallboard clients out there. If you do it correctly, it works very well. If you do it incorrectly, you will load up the AW so much that it will be an issue.
Regards,
Geoff