IIS 6.0 Application Isolation Modes Overview 

In order to separate and protect ASP.NET applications that run simultaneously, Internet Information Services (IIS) 6.0 provides two different application isolation modes. By default, worker process isolation mode is used. However, IIS 5.0 isolation mode is also provided for backward compatibility. The following sections describe the two application isolation modes and how to set the mode.

The default application isolation mode in IIS 6.0 is worker process isolation mode. In this mode, the process model built into ASP.NET is disabled, and the worker process isolation architecture of IIS 6.0 is used instead. Any configuration settings that are specified in the <processModel> element of the Machine.config file are disregarded, except for the following attributes:

• maxWorkerThreads

• maxIoThreads

• responseDeadlockInterval

To specify values for other process model attributes, you must use the appropriate application pool setting. For information about setting the appropriate application pool settings, see Application Pool Settings for Worker Process Isolation Mode.

When IIS 6.0 is in IIS 5.0 isolation mode, the worker process isolation architecture of IIS 6.0 is disabled and the process model build into ASP.NET is used for all ASP.NET applications on the computer. In this mode, the process model settings are specified through the <processModel> element of the Machine.config file.

For more information on configuring the process model settings when using IIS 5.0 isolation mode, see ASP.NET Configuration Overview.

How to: Set the Application Isolation Mode in IIS 6.0

processModel Element (ASP.NET Settings Schema)

Mapping ASP.NET Process Model Settings to IIS 6.0 Application Pool Settings
ASP.NET Configuration Overview

IIS 6.0 Application Isolation Modes
Application Pool Settings for Worker Process Isolation Mode