Its RdpViewer is an add-on to enable launching remote desktop connection rights from the document library in SharePoint. It is deployed as an extension to existing file menu (known as Edit Control Block).
The menu will be active only when the users select *.RDP file type anywhere in SharePoint site.
Once the command is selected, it will detect browser capability and launch RDP connection on the client.
If the client browser doesn't have necessary MsRdpWebAccess ActiveX from Microsoft - it will offers download link so that the user will be able to save and open it as normally they do.