A new generation of Web applications puts a greater demand on performance and scalability attributes of Web servers. IIS is the next generation of Web server available in the Windows Server 2003 platform with highly reliable, manageable, and scalable Web application infrastructure for all versions of Windows Server 2003.IIS 6.0 is a key component of the Windows Server 2003 application platform, using which you can develop and deploy high performance ASP.NET Web applications, and XML Web Services. In addition, IIS 6.0 provides a high-performance platform for applications built using the Microsoft .NET Framework.<o:p> </o:p>
IIS 6.0 supports the Microsoft Dynamic Systems Initiative (DSI) with automated health monitoring, process isolation, and improved management capabilities. IIS helps organizations increase Web site and application availability while lowering system administration costs. <o:p></o:p>
Today lets understand the IIS 5.0 architecture as it is the base for us to understand the architecture of IIS 6.0, which is the latest version of it. In IIS 5.0, there was only one main process, represented by the executable inetinfo.exe, that was designed to function as the main Web server process, which could route requests to one or more out-of-process applications that are running within the dllhost.exe. With this architecture, Inetinfo.exe is the master process through which each request must traverse regardless of isolation mode. IIS 5.0 had three isolation modes: In-Process, Out-of-process, and Pooled. In the
In-Process mode, all the applications run in the same process as that of the Web server (inetinfo.exe). The IIS 5.0 default mode is Pooled, in which the Web server (Inetinfo.exe) runs in its own process and all other applications will run in one single-pooled process (dllhost.exe). You can set high-priority applications to run as Isolated, which creates another instance of dllhost.exe. Even though this out-of-process isolation allows you to increase the fault-tolerance of your Web server, it is slow in terms of performance. The Pooled mode is the best performance/isolation tradeoff, but there is only one pool on a server and all pooled applications must use the same pool.
From,
Shiva Chaitanya
Student Champ
Aurora's Engineering College
