On Remote Desktop Web Access (RD Web Access) Server, there are two URLs available to serve the connection feed. You need to choose one depending on the extensibility scenario.

1. “/rdweb/pages/webfeed.aspx” URL:
   This URL is used for RD Web Access website extensibility. You can create a new web page similar to the RD Web Access default webpage. Below are some of the features that are possible by using this URL

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  • Branding or customizations for your customers or organization.
  • Visually sorting or segregating remote resource types (e.g. RemoteApp and Remote Desktop resources).
  • Filtering remote resources at display time (for example, additional filtering apart from RemoteApp filtering ).
  • Silverlight-based webpage for a rich user experience.

By using this connection feed URL

• There is no need to write a custom authentication mechanism because the webpage runs within the RD Web Access web application.
• It is easier to support Single Sign On for launching remote resources. In a future post, we will cover on how to enable SSO.

2. “/rdweb/feed/webfeed.aspx” URL:
   This URL can also be used to provide extensibility and is more flexible than the above URL. In addition to above feature set, below are some of the other features that are possible by using this URL:

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  • Creating new client applications similar to RemoteApp and Desktop Connections for downlevel windows clients and for thin clients.
  • Creating new web portal similar to RD Web Access, not just a webpage alone.
  • Integrating remote resource presentation with your existing web portal.

By using this connection feed URL

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  • Client applications get an authentication cookie that will not expire. This can be used for easier automatic updates without re-prompting user for credentials.

Here is a sample connection XML containing information about remote resources..

Source: http://blogs.msdn.com/rds/archive/2009/12/17/remoteapp-and-desktop-connection-feed-extensibility.aspx