We have a PeopleSoft installation and I am building a separate web application that needs to pull data from the PeopleSoft database. The web application will be on a different server than PeopleSoft, but the same internal network.
What are my options?
Yes - Integration Broker is Peoplesoft's proprietary implementation of a publish/subscribe mechanism, speaking xml. You could of course just write code that goes against your database using JDBC or OLE/ODBC. Nothing keeps you from doing this. However, you must understand the Peoplesoft database schema, so that you are pulling from, or inserting/updating/deleting all of the proper data. Peoplesoft takes care of this for you.
Also, check out Component Interfaces - and they are exposed as an API to Java or C/C++.