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Microsoft SQL Server Analysis Services supports a thin client architecture. The Analysis Services calculation engine is entirely server-based, so all queries are resolved on the server. As a result, only a single round trip between the client and the server is required for each query, resulting in scalable performance as queries increase in complexity.

The native protocol for Analysis Services is XML for Analysis (XML/A). Analysis Services provides several data access interfaces for client applications, but all of these components communicate with an instance of Analysis Services using XML for Analysis.

Several different providers are provided with Analysis Services to support different programming languages. A provider communicates with an Analysis Services server by sending and receiving XML for Analysis in SOAP packets over TCP/IP or over HTTP through Internet Information Services (IIS). An HTTP connection uses a COM object instantiated by IIS, called a data pump, which acts as a conduit for Analysis Services data. The data pump does not examine the underlying data contained in the HTTP stream in any way, nor are any of the underlying data structures available to any of the code in the data library itself.

Win32 client applications can connect to an Analysis Services server using OLE DB for OLAP interfaces or the Microsoft® ActiveX® Data Objects (ADO) object model for Component Object Model (COM) automation languages, such as Microsoft Visual Basic®. Applications coded with .NET languages can connect to an Analysis Services server using ADO MD.NET.

Existing applications can communicate with Analysis Services without modification simply by using one of the Analysis Services providers.

Analysis Services has a Web architecture with a fully scalable middle tier for deployment by both small and large organizations. Analysis Services provides broad middle tier support for Web services. ASP applications are supported by OLE DB for OLAP and ADO MD, ASP.NET applications are supported by ADOMD.NET. The middle tier, illustrated in the following figure, is scalable to many concurrent users.

Both client and middle tier applications can communicate directly with Analysis Services without using a provider. Client and middle tier applications may send XML for Analysis in SOAP packets over TCP/IP, HTTP, or HTTPS. The client may be coded using any language that supports SOAP. Communication in this case is most easily managed by Internet Information Services (IIS) using HTTP, although a direct connection to the server using TCP/IP may also be coded. This is the thinnest possible client solution for Analysis Services.