The Microsoft® Office Information Bridge Framework connects Microsoft Office applications with compatible Web services or common language runtime (CLR) services that are written for line-of-business (LOB) services, such as accounting, supply chain management, and resource planning applications. With this system, users can interact with LOB services directly from content that is hosted by Microsoft Office Word 2003, Microsoft Office Excel 2003, and Microsoft Office Outlook® 2003.
I did not know that the full IBF planning and architecture guide is available online here (tx dotnetfindserv).