Starting with IBM WebSphere Application Server Version 3.0, the JDBC 2.0 Standard Extension APIs provide connection pooling capability to make more efficient use of data server connections.
Prior to Application Server Version 3.0, the JDBC 2.0 Standard Extension APIs were not available. The connection pooling capability was provided by the IBM connection manager.
A servlet would communicate with a connection manager that maintained a pool of open data server connections to JDBC or ODBC data server products. When the servlet received a connection from the pool, it could communicate directly with the data server using its APIs.
The connection manager remains supported in Version 3.5 (but deprecated), but it is highly recommended you migrate applications to use the new connection pooling model.