IIS 8.0 WebSocket Protocol Support

by Microsoft


Version Notes
IIS 8.0 The WebSocket Protocol was introduced in IIS 8.0.
IIS 7.5 The WebSocket Protocol was not supported in IIS 7.5.
IIS 7.0 The WebSocket Protocol was not supported in IIS 7.0.


One of the limitations to HTTP is that it was designed as a one-directional method of communication. However, many modern web-based applications require more real-time, two-way communications in order to function optimally.


With the release of Windows Server 2012 and Windows 8, Internet Information Services (IIS) 8.0 has added support for the WebSocket Protocol.

The WebSocket Protocol is an open standard that is defined in RFC 6455, and developers can use this functionality to create applications that implement two-way communications over the Internet between a client and server. For more information about the WebSocket Protocol, see the following articles:

Step by Step Instructions

To enable support for the WebSocket Protocol on Windows Server 2012, use the following steps:

  1. Open Server Manager.
  2. Under the Manage menu, click Add Roles and Features.
  3. Select Role-based or Feature-based Installation, and then click Next.
  4. Select the appropriate server, (your local server is selected by default), and then click Next.
  5. Expand Web Server (IIS) in the Roles tree, then expand Web Server, and then expand Application Development.
  6. Select WebSocket Protocol, and then click Next.
  7. If no additional features are needed, click Next.
  8. Click Install.
  9. When the installation completes, click Close to exit the wizard.


Disable WebSocket when using socket.io on node.js

If you are using the WebSocket support in socket.io on node.js in your site, you will need to disable the default IIS WebSockets module by adding the below snippet to your web.config or applicationHost.config. If this is not done, the IIS WebSockets module will attempt to handle the WebSocket communication rather than letting this task fall through to node.js (and hence your application). This will result in unexpected errors when you attempt to access your site.

    <webSocket enabled="false"/>


IIS 8.0 has added support for WebSocket Protocol, which enables dynamic, two-way communications over the Internet. Additional information can be found on the following URLs: