In SharePoint only a user can connect a WSRP viewer web part to a trusted producer. Any producer that has been configured for use in the farm by the SharePoint administrator is known as trusted producer. End users are restricted to add trusted producers and cannot override the settings so that end users and sharepoint environment can be protected from malicious remote portlet.

How to add a trusted:

SharePoint administrator have to create a TrustedWSRPProducers.config file in the “C:\program files\Microsoft Office Server\14.0\Config” folder on the SharePoint web front ends.  

TrustedWSRPProducers.config  sample file: 

<Configuration >
<Producer Name="NetUnity" AllowScripts="true">
<ServiceDescriptionURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</ServiceDescriptionURL>
<RegistrationURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</RegistrationURL>
<MarkupURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</MarkupURL>  
<PortletManagementURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</PortletManagementURL>
</Producer>
</Configuration>

 Now place the file “C:\program files\Microsoft Office Server\14.0\Config” folder on the SharePoint web front ends a user can configure the WSRP Viewer web part.

After adding WSRP viewer web part to a site the designer or administrator have to open up the web parts configuration panel to modify a few settings.

Producer Modification:  

A drop down lists out available producers TrustedWSRPProducers.config file.   After the producer is selected the portlet drop down selector will populate with the available values for the selected producer. Select the desired portlet, click the OK button to save these settings. 

For additional configuration SharePoint site must be switched to edit mode and then the Edit Web Part option needs to be selected from the WSRP viewer web part drop down menu.

Edit mode display the web parts configuration tool pane along with displaying additional portlet configuration information in the location of the web part on the SharePoint site.

The webpart will display the news feed from yahoo as shown below.

WSRP is one of many portals when working with SharePoint 2010. SharePoint’s business connectivity services and creating custom data view webParts from web services  using SharePoint Designer.