ODBC Datasource Name and Connection Userid and Password
In order to access a database to map userids to proper Windows NT Accounts, bcAuthenticate Filter needs to know your ODBC Data Source Name. Most databases will require a userid and password to be able to connect to the database as well. Examples of SQL Statements and database table layouts are shown in “Mapping Users” topic.
Maximum Number of Database Connections
Some databases are configured not to allow more than a specified number of connections. For example, if your database allows maximum 40 connections, then you may want to configure the bcAuthenticate filter not to open more the 35 concurrent connections at a time, assuming the other 5 connections are sufficient for other applications that may be using your database. This is needed because if an application requests a connection and the database engine has already granted maximum number of connections, it is likely to return an error and deny the connection request.
This maximum connection limit does not imply anything about concurrent visitors to your website. It merely limits the number of concurrent database access that happens in a split second. If you set the maximum to 40, you can potentially still have hundreds or thousands of concurrent users online.
Impersonating the Windows User id used to access database
Some systems may be configured such that IIS Windows NT Account may not have correct permissions to access the database server. In such a case, the bcAuthenticate needs to be told which Windows User Logon to use to execute database code.