SAS® AppDev Studio 3.0 Developer's Site

webAF Middleware Server

Note: With SAS AppDev Studio Version 3.0, the Middleware Server (MWS) is being deprecated in favor of the scalability features provided by SAS Integration Technologies software. You can still continue to use the MWS for existing applications or new development. However, if you are using the IOM Protocol to support communication from your remote clients, we highly recommend that you use the SAS Integration Technologies load balancing and workspace pooling support instead of using the similar features provided by the MWS. For more information, see the SAS AppDev Studio 3.0 Migration Guide.


The MWS is a Java application that typically resides on the Web server. It enables you to

MWS can be used with webAF and webEIS, two products that require users to make connections to SAS servers to access data. Without MWS, a new SAS session would be started (and eventually shut down) each time a user makes a connection to retrieve data. This process is very inefficient and time-consuming. MWS, or funneling, offers a scalable solution to this problem, although it does handle only one client request at a time:

Middleware Server Funnel Diagram

Note: You could use tunneling to make socket connections to machines other than the Web server, but tunneling typically provides poor performance. Like tunneling, MWS enables you to have the SAS Server and Web Server on different machines, if needed.

For more information, see