What is the difference between 'classic' and 'integrated' pipeline mode in IIS7? - asp.net

I was deploying an ASP.NET MVC application last night, and found out that it is less work to deploy with IIS7 set to integrated mode. My question is what is the difference? And what are the implications of using one or the other?

Classic mode (the only mode in IIS6 and below) is a mode where IIS only works with ISAPI extensions and ISAPI filters directly. In fact, in this mode, ASP.NET is just an ISAPI extension (aspnet_isapi.dll) and an ISAPI filter (aspnet_filter.dll). IIS just treats ASP.NET as an external plugin implemented in ISAPI and works with it like a black box (and only when it's needs to give out the request to ASP.NET). In this mode, ASP.NET is not much different from PHP or other technologies for IIS.
Integrated mode, on the other hand, is a new mode in IIS7 where IIS pipeline is tightly integrated (i.e. is just the same) as ASP.NET request pipeline. ASP.NET can see every request it wants to and manipulate things along the way. ASP.NET is no longer treated as an external plugin. It's completely blended and integrated in IIS. In this mode, ASP.NET HttpModules basically have nearly as much power as an ISAPI filter would have had and ASP.NET HttpHandlers can have nearly equivalent capability as an ISAPI extension could have. In this mode, ASP.NET is basically a part of IIS.

Integrated application pool mode
When an application pool is in Integrated mode, you can take advantage
of the integrated request-processing architecture of IIS and ASP.NET.
When a worker process in an application pool receives a request, the
request passes through an ordered list of events. Each event calls the
necessary native and managed modules to process portions of the
request and to generate the response.
There are several benefits to running application pools in Integrated
mode. First the request-processing models of IIS and ASP.NET are
integrated into a unified process model. This model eliminates steps
that were previously duplicated in IIS and ASP.NET, such as
authentication. Additionally, Integrated mode enables the availability
of managed features to all content types.
Classic application pool mode
When an application pool is in Classic mode, IIS 7.0 handles requests
as in IIS 6.0 worker process isolation mode. ASP.NET requests first go
through native processing steps in IIS and are then routed to
Aspnet_isapi.dll for processing of managed code in the managed
runtime. Finally, the request is routed back through IIS to send the
response.
This separation of the IIS and ASP.NET request-processing models
results in duplication of some processing steps, such as
authentication and authorization. Additionally, managed code features,
such as forms authentication, are only available to ASP.NET
applications or applications for which you have script mapped all
requests to be handled by aspnet_isapi.dll.
Be sure to test your existing applications for compatibility in
Integrated mode before upgrading a production environment to IIS 7.0
and assigning applications to application pools in Integrated mode.
You should only add an application to an application pool in Classic
mode if the application fails to work in Integrated mode. For example,
your application might rely on an authentication token passed from IIS
to the managed runtime, and, due to the new architecture in IIS 7.0,
the process breaks your application.
Taken from: What is the difference between DefaultAppPool and Classic .NET AppPool in IIS7?
Original source: Introduction to IIS Architecture

IIS 6.0 and previous versions :
ASP.NET integrated with IIS via an ISAPI extension, a C API ( C Programming language based API ) and exposed its own application and request processing model.
This effectively exposed two separate server( request / response ) pipelines, one for native ISAPI filters and extension components, and another for managed application components. ASP.NET components would execute entirely inside the ASP.NET ISAPI extension bubble AND ONLY for requests mapped to ASP.NET in the IIS script map configuration.
Requests to non ASP.NET content types:- images, text files, HTML pages, and script-less ASP pages, were processed by IIS or other ISAPI extensions and were NOT visible to ASP.NET.
The major limitation of this model was that services provided by ASP.NET modules and custom ASP.NET application code were NOT available to non ASP.NET requests
What's a SCRIPT MAP ?
Script maps are used to associate file extensions with the ISAPI handler that executes when that file type is requested. The script map also has an optional setting that verifies that the physical file associated with the request exists before allowing the request to be processed
A good example can be seen here
IIS 7 and above
IIS 7.0 and above have been re-engineered from the ground up to provide a brand new C++ API based ISAPI.
IIS 7.0 and above integrates the ASP.NET runtime with the core functionality of the Web Server, providing a unified(single) request processing pipeline that is exposed to both native and managed components known as modules ( IHttpModules )
What this means is that IIS 7 processes requests that arrive for any content type, with both NON ASP.NET Modules / native IIS modules and ASP.NET modules providing request processing in all stages This is the reason why NON ASP.NET content types (.html, static files ) can be handled by .NET modules.
You can build new managed modules (IHttpModule) that have the ability to execute for all application content, and provided an enhanced set of request processing services to your application.
Add new managed Handlers ( IHttpHandler)

In classic mode IIS works h ISAPI extensions and ISAPI filters directly. And uses two pipe lines , one for native code and other for managed code. You can simply say that in Classic mode IIS 7.x works just as IIS 6 and you dont get extra benefits out of IIS 7.x features.
In integrated mode IIS and ASP.Net are tightly coupled rather then depending on just two DLLs on Asp.net as in case of classic mode.

Related

ASP.NET Core Web API living inside a ASP.NET 4 IIS Web Site

I am tasked to to build a Web API application. The app will be hosted inside an existing web site - a pre-ASP.NET 5 web application with a WCF web service.
I wonder - can I build the web-api application using ASP.NET Core 1 in a way that it can happily exists as a sub application inside the already existing site in IIS?
Thanks!
Yes, this is possible, I'm doing the opposite of this scenario but conceptually its the same thing. You need to create your subsite as a separate application in IIS with its own app pool. That app pool needs to be configured No Managed Code per the instructions on the Docs site https://docs.asp.net/en/latest/publishing/iis.html
The only other thing you need to watch out for is that the web.config in the subsite will inherit some settings from the root web.config, so you need to remove or clear things sometimes like handlers, modules, etc.
If I understand you correctly it is not possible what you want. Please refer to the following documentation about hosting ASP.NET Core on IIS: https://docs.asp.net/en/latest/publishing/iis.html.
If you specifically look at the .NET CLR version in the application pool it should be "No Managed Code" while your current website is set to a .NET framework version I assume. This is because ASP.NET Core is now cross plaform and completely web server agnostic. It even needs a little 'trick' (the ASP.NET Core Module) to work on IIS. See: "The module creates the reverse-proxy between IIS and the Kestrel server."
But if you follow the link provided above I think you'll manage to work it out.

Host ASP.NET App In WCF or Generic Web Server

Objective:
We have a Windows Service/generic EXE that also hosts a WCF service (.Net 3.5). I'd like to be able to take a third party ASP.NET component in a DLL, and host it through that WCF Service.
Is this possible to do, in any way?
It seems like if you want to host a ASP.NET app, it must be through IIS, but we don't use IIS.
Is there any way that we could load the ASP.NET app into memory, make the app available through an endpoint, and receive requests back from the app?
Specifically, we'd like to take the "Microsoft.ReportViewer.WebForms.dll", expose the web form in a web page, and accept any requests back from the web form.
http://msdn.microsoft.com/en-us/library/ms251723.aspx
Looking for anything to get me started. Thx.
From owin.org
"OWIN defines a standard interface between .NET web servers and web applications. The goal of the OWIN interface is to decouple server and application, encourage the development of simple modules for .NET web development, and, by being an open standard, stimulate the open source ecosystem of .NET web development tools."
Essentially Owin implementations, like Katana (OWIN implementations for Microsoft servers and frameworks.), help you self host web apps, even in a Windows NT Service.
According to this post, hosting a WebForms app outside IIS/ASP.NET is not possible.
WebForms are tightly coupled to ASP.NET/IIS and cannot run directly on
OWIN/Katana (e.g. outside of ASP.NET/IIS). However, you should be able
to use Katana's middleware (Security, CORS, etc.) in a WebForms
application.
http://katanaproject.codeplex.com/discussions/571291

iis isapi and asp.net,what's the relationship of them?

iis isapi and asp.net,what's the relationship of them?
eg: a request send to server,question 1 :please describe a simple process workflow .
Q2:
did a request can be handle by asp.net engine and isapi in order? or only one can hanle the request?
Depends which version of IIS you are referring to.
The asp.net engine WAS invoked by the isapi before Integrated Pipeline mode existed. In classic mode (or prior to integrated pipeline) the isapi extension was invoked and used interop to call off into asp.net for the request.
Since the Integrated Pipeline is the main mode used now, check out:
http://drdobbs.com/windows/219501263
http://msdn.microsoft.com/en-us/magazine/cc135973.aspx

What is the difference between Classic and Integrated pipeline mode in IIS7? [duplicate]

I was deploying an ASP.NET MVC application last night, and found out that it is less work to deploy with IIS7 set to integrated mode. My question is what is the difference? And what are the implications of using one or the other?
Classic mode (the only mode in IIS6 and below) is a mode where IIS only works with ISAPI extensions and ISAPI filters directly. In fact, in this mode, ASP.NET is just an ISAPI extension (aspnet_isapi.dll) and an ISAPI filter (aspnet_filter.dll). IIS just treats ASP.NET as an external plugin implemented in ISAPI and works with it like a black box (and only when it's needs to give out the request to ASP.NET). In this mode, ASP.NET is not much different from PHP or other technologies for IIS.
Integrated mode, on the other hand, is a new mode in IIS7 where IIS pipeline is tightly integrated (i.e. is just the same) as ASP.NET request pipeline. ASP.NET can see every request it wants to and manipulate things along the way. ASP.NET is no longer treated as an external plugin. It's completely blended and integrated in IIS. In this mode, ASP.NET HttpModules basically have nearly as much power as an ISAPI filter would have had and ASP.NET HttpHandlers can have nearly equivalent capability as an ISAPI extension could have. In this mode, ASP.NET is basically a part of IIS.
Integrated application pool mode
When an application pool is in Integrated mode, you can take advantage
of the integrated request-processing architecture of IIS and ASP.NET.
When a worker process in an application pool receives a request, the
request passes through an ordered list of events. Each event calls the
necessary native and managed modules to process portions of the
request and to generate the response.
There are several benefits to running application pools in Integrated
mode. First the request-processing models of IIS and ASP.NET are
integrated into a unified process model. This model eliminates steps
that were previously duplicated in IIS and ASP.NET, such as
authentication. Additionally, Integrated mode enables the availability
of managed features to all content types.
Classic application pool mode
When an application pool is in Classic mode, IIS 7.0 handles requests
as in IIS 6.0 worker process isolation mode. ASP.NET requests first go
through native processing steps in IIS and are then routed to
Aspnet_isapi.dll for processing of managed code in the managed
runtime. Finally, the request is routed back through IIS to send the
response.
This separation of the IIS and ASP.NET request-processing models
results in duplication of some processing steps, such as
authentication and authorization. Additionally, managed code features,
such as forms authentication, are only available to ASP.NET
applications or applications for which you have script mapped all
requests to be handled by aspnet_isapi.dll.
Be sure to test your existing applications for compatibility in
Integrated mode before upgrading a production environment to IIS 7.0
and assigning applications to application pools in Integrated mode.
You should only add an application to an application pool in Classic
mode if the application fails to work in Integrated mode. For example,
your application might rely on an authentication token passed from IIS
to the managed runtime, and, due to the new architecture in IIS 7.0,
the process breaks your application.
Taken from: What is the difference between DefaultAppPool and Classic .NET AppPool in IIS7?
Original source: Introduction to IIS Architecture
IIS 6.0 and previous versions :
ASP.NET integrated with IIS via an ISAPI extension, a C API ( C Programming language based API ) and exposed its own application and request processing model.
This effectively exposed two separate server( request / response ) pipelines, one for native ISAPI filters and extension components, and another for managed application components. ASP.NET components would execute entirely inside the ASP.NET ISAPI extension bubble AND ONLY for requests mapped to ASP.NET in the IIS script map configuration.
Requests to non ASP.NET content types:- images, text files, HTML pages, and script-less ASP pages, were processed by IIS or other ISAPI extensions and were NOT visible to ASP.NET.
The major limitation of this model was that services provided by ASP.NET modules and custom ASP.NET application code were NOT available to non ASP.NET requests
What's a SCRIPT MAP ?
Script maps are used to associate file extensions with the ISAPI handler that executes when that file type is requested. The script map also has an optional setting that verifies that the physical file associated with the request exists before allowing the request to be processed
A good example can be seen here
IIS 7 and above
IIS 7.0 and above have been re-engineered from the ground up to provide a brand new C++ API based ISAPI.
IIS 7.0 and above integrates the ASP.NET runtime with the core functionality of the Web Server, providing a unified(single) request processing pipeline that is exposed to both native and managed components known as modules ( IHttpModules )
What this means is that IIS 7 processes requests that arrive for any content type, with both NON ASP.NET Modules / native IIS modules and ASP.NET modules providing request processing in all stages This is the reason why NON ASP.NET content types (.html, static files ) can be handled by .NET modules.
You can build new managed modules (IHttpModule) that have the ability to execute for all application content, and provided an enhanced set of request processing services to your application.
Add new managed Handlers ( IHttpHandler)
In classic mode IIS works h ISAPI extensions and ISAPI filters directly. And uses two pipe lines , one for native code and other for managed code. You can simply say that in Classic mode IIS 7.x works just as IIS 6 and you dont get extra benefits out of IIS 7.x features.
In integrated mode IIS and ASP.Net are tightly coupled rather then depending on just two DLLs on Asp.net as in case of classic mode.

ASP.NET: What does this HttpModule do? System.ServiceModel.Activation.HttpModule

Can anyone tell me the purpose of this HttpModule? It's showing up on my HttpModuleCollection list, but I don't know what's it's for.
System.ServiceModel.Activation.HttpModule
I can't find any documentation on it.
System.ServiceModel.Activation.HttpModule come from because you installed "Microsoft .NET Framework 3.5.1" / "Windows Communication Foundation HTTP Activation" feature. If you don't need the feature you can uninstall it of remove the module from your web.config. The less unused modules you load the more quickly run your web application.
If you install this feature after the installation of .NET 4 framework on your server you can receive problems described in http://blogs.iis.net/webtopics/archive/2010/04/28/system-typeloadexception-for-system-servicemodel-activation-httpmodule-in-asp-net-4.aspx.
In general an HTTP module is called on every request in response to the BeginRequest() and EndRequest() events. As a result, the module runs before and after a request is processed. In the section "How HTTP Modules Work" on http://msdn.microsoft.com/en-us/library/bb398986(v=VS.100).aspx you can read more about HTTP modules.
http://msdn.microsoft.com/en-us/library/ms227673.aspx describes how to create a Custom HTTP Module. Some small custom modules can be really helpful. For example, you can read in How to remove the ".svc" extension in RESTful WCF service? a code example (which originate from the book "RESTful .NET", Chapter 5, page 96) "Removing the .SVC Extension from WCF REST URLs". In http://www.west-wind.com/weblog/posts/570695.aspx you can read how to do the same with respect of "IIS 7 Rewrite Module".
The general information about HTTP module is not a part of your question, but I inserted it to better understanding what Activation.HttpModule do, and what other more useful modules you can use or write yourself.
This module is what allows WCF (Windows Communication Foundation) services to work (starting in .net Framework 3.0).
You can safely ignore it and it shouldn't cause trouble. If you really want to get rid of it, you can remove it from your root web.config file (e.g. in
\Windows\Microsoft.NET\Framework\v4.0.30319\Config\web.config). But I suggest leaving it there just in case you need WCF at some point.
A http module is a .net assembly that is called every time your web application gets a request. This is the standard one that asp.net provides that connects your .net web application code to the IIS web infrastructure.
See here for an explanation.
HTTP Modules
An HTTP module is an assembly that is
called on every request that is made
to your application. HTTP modules are
called as part of the request pipeline
and have access to life-cycle events
throughout the request. HTTP modules
therefore let you examine incoming
requests and take action based on the
request. They also let you examine the
outgoing response and modify it.
In IIS 6.0, the ASP.NET request
pipeline is separate from the Web
server request pipeline. In IIS 7.0,
the ASP.NET request pipeline and the
Web server request pipeline can be
integrated into a common request
pipeline. In IIS 7.0, this is referred
to as Integrated mode. The unified
pipeline has several benefits for
ASP.NET developers. For example, it
lets managed-code modules receive
pipeline notifications for all
requests, even if the requests are not
for ASP.NET resources. However, if you
want, you can run IIS 7.0 in Classic
mode, which emulates ASP.NET running
in IIS 6.0. For more information, see
ASP.NET Application Life Cycle
Overview for IIS 7.0.
ASP.NET HTTP modules are like ISAPI
filters because they are invoked for
all requests. However, they are
written in managed code and are fully
integrated with the life cycle of an
ASP.NET application. You can put
custom module source code in the
App_Code folder of your application,
or you can put compiled custom modules
as assemblies in the Bin folder of an
application.
ASP.NET uses modules to implement
various application features, which
includes forms authentication,
caching, session state, and client
script services. In each case, when
those services are enabled, the module
is called as part of a request and
performs tasks that are outside the
scope of any single page request.
Modules can consume application events
and can raise events that can be
handled in the Global.asax file. For
more information about application
events, see ASP.NET Application Life
Cycle Overview for IIS 5.0 and 6.0 and
ASP.NET Application Life Cycle
Overview for IIS 7.0.

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