Companies that are creating an implementation of the Remote Desktop Protocol set can license the Intellectual Property(IP) rights they need from Microsoft by signing the RDP Client License. Products that might need these rights to interact with Windows Remote Desktop Servers (Sessions or VM based) include:
Non-Windows Thin Client devices
Non-Windows based client software
To understand if you might need the patent rights associated with the protocols, Microsoft has also published a map of which patents are associated with each protocol.
Free attendance at protocol plugfest events: these are quarterly meetings where attendees receive presentations about a specific area of protocol technology and have a chance to interact directly with Microsoft engineers.
Network Monitoring (NetMon) tool, a protocol analyzer that allows you to capture network traffic, view and analyze it.
Test Suites: Microsoft has begun releasing test suites for different protocols and will continue to roll them out over time.
Reference Source Code
: Microsoft will shortly be making available reference source code for an implementation of RDP 7.1 only to RDP Client licensees. Look for a future blog post for more information.