BCS Integration - Overview

Microsoft Business Connectivity Services (BCS), formerly named the Business Data Catalog, enables users to read and write data from external systems - through Web services, databases, and Microsoft .NET Framework assemblies - from within Microsoft SharePoint 2010 and Microsoft Office 2010 applications. Both SharePoint 2010 and Office 2010 applications have product features that can use external data directly, both online and offline. Developers can gain access to a rich set of features and rapidly build solutions by using familiar tools such as Microsoft Visual Studio 2010 and Microsoft SharePoint Designer 2010.

Common Terminology:

Terminology	Description
BCS - Business Connectivity Services	BCS is the name of the new feature in SharePoint 2010 that is the evolution of BDC from SharePoint 2007 with the additional capabilities such as External Content Types and External Lists
BDC - Business Data Catalog	BDC service is the new version of the Business Data Catalog from SharePoint 2007 now available as a SharePoint 2010 shared service
ECT - External Content Type	ECTs are reusable metadata descriptions of connectivity information and data definitions plus the behaviors you want to apply to a certain category of external data - every BCS user interface requires an underlying ECT configuration
EL - External Lists	BCS supports many user interfaces for interacting with data - the External List is the most frequently mentioned as it is the easiest to understand and it provides the foundation for additional downstream user interfaces, such as Outlook

Key BCS Features:

Read-write. You can create, read, update and delete external data from SharePoint and Office applications.
More connectivity options. In addition to database and web services, connect to WCF services or plug your own code into a .Net assembly connector to handle transformation or aggregation of data. Full support for Claims-enabled services as well as Secure Store Service (formerly SSO) to map user credentials.
Design and customization tools. SharePoint Designer 2010 and Visual Studio 2010 allow creation of code-less and code-based solutions. Composite solutions can be collaboratively built by a team with each member using the tool of their choice.
Rich Client integration. Expose data as a native SharePoint list and then connect it to SharePoint Workspace or Outlook. Customize InfoPath forms to add business logic surfaced consistently in SharePoint and SharePoint Workspace. Customize Outlook declaratively to provide views, forms, ribbon buttons, or show contextual data in a task pane.
Work online or offline. External data is cached in a SQL CE database installed with Office 2010. When connectivity is lost, the cache automatically goes into offline mode. When connectivity is restored, BCS can synchronize data changes directly to the external system.
Application Lifecycle. Deploy composite SharePoint solutions to Office 2010 machines, and enable users to check for updates to those solutions.