Biztalk Server 2004 Business Rule Engine Basic concepts

Basic concepts BRE
Facts are the entities that your rules consume and manipulate – examples include an element that appears in an XML document, a column in a database table, or even a method exposed by a .NET component.
A vocabulary is a collection of facts, and its purpose is both to apply meaningful, user-defined definition names to those facts and to provide a unit of versioning
A rule is a statement that defines the behavior of one aspect of a business process. rules are made up of facts, conditions and actions.
A policy is a set of rules, packaged and versioned as a unit. Policies are what you develop, test, and deploy when working with the Business Rules Framework

Single Sign-On (SSO)

SSO
Enterprise Single Sign-On (SSO) provides services to store and transmit encrypted user credentials across local and network boundaries, including domain boundaries. SSO stores the credentials in the Credential database. Because SSO provides a generic single sign-on solution, middleware applications and custom adapters can leverage SSO to securely store and transmit user credentials across the environment.The sub services of the Enterprise Single Sign-On (SSO) service are:
Mapping. This component maps the user account in the Windows system to the user accounts in the back-end systems (affiliate applications).
Lookup. This component looks up the user credentials in the Credential database in the back-end system. This is the SSO runtime component.
Administration. This component manages the affiliate applications and the mappings for each affiliate application.
Secret. This component generates the master secret and distributes it to the other SSO servers in the system. It is only active on the Single Sign-On server that is acting as the master secret server.

Calling Unmanaged Dll's from Managed Code

Calling Unmanaged Dll's from Managed CodeThis is a very comprehensive Tutorial on the underlying PInvoke that is responsile for calling the C++ Dll's from the Code of C#.http://msdn.microsoft.com/library/default.asp?url=/library/en-us/csref/html/vcwlkplatforminvoketutorial.asp