Microsoft Interoperability Case Study

Microsoft Interoperability Case Study

Terminal Servers: Addressing a Growing Business Problem

Microsoft Open Protocols Program partner Aqua Connect noticed an underserved market within the terminal server space: the need for a Macintosh-based solution that was also compatible with the Microsoft Windows platform. As the use of thin clients and remote users increased within organizations, the need for different environments for these computers to operate in grew as well. While there were plenty of Windows-based terminal servers on the market, there were no Macintosh-based terminal servers available.

Typically, there are three main market segments that use terminal servers on a regular basis:

  • Data secured configuration - Organizations can deploy terminal servers so all data can be monitored and controlled by an IT department. Users can access the data through smart cards and biometrics to edit and review the data in a secure environment.
  • Thin client hardware configuration - The use of terminal servers allows an organization to save money on hardware as thin clients are more durable and IT departments do not need to travel as frequently to locations, centralizing support staff.
  • sp;  Hardware reduced configuration - Organizations that need both a secure environment and hardware reduced configuration requirements can utilize terminal servers to keep content secure, but also have costs in check.

These organizations often purchase software based on the current hardware already in use. However, many of the software solutions only work on one OS platform. MacPractice, for example, is an Apple software solution used by medical practices to handle billing, scheduling, medical records, etc. To use this software, an office would need to change out all of its hardware and replace it with Macs. Or, in the case of Aqua Connect, use a Macintosh terminal server that is compatible with other operating systems to enable their machines to use the software without purchasing or replacing hardware.

Why Aqua Connect Chose Microsoft Open Protocols over Third-Party Solutions

To create a successful terminal server for the Mac OS environment, the specific protocols were critical to its success. Aqua Connect originally tried the Virtual Network Computing (VNC) and the X11R6 protocols to handle the remote desktop aspects of its server. However, each had their limitations based on Aqua Connect’s needs:


  • While the VNC protocol is open source, well-documented and simple to implement, it offered no sound, printing or other advanced features. Additionally, it had no real ability for compression or performance-enhancing features. Most importantly, thin clients do not support this protocol.
  • Later, Aqua Connect added in the X11R6 protocol. While it had thin client compatibility and an established protocol that is friendly with Windows, Linux and Mac-based machines, it was an older protocol that offered no compression, sound, printer redirection or performance enhancing features.

Aqua Connect considered implementing its own version of the Remote Desktop Protocol (RDP) or using a third party version of the RDP protocol. Both of these choices have significant limitations, including: limited reliability, incomplete implementations, lack of documentation, no established support and/or buggy solutions. Each of these limitations turned out to be more expensive than simply licensing the RDP protocol patents directly from Microsoft. Additionally, as Microsoft continues to improve and enhance its open protocols over time, implementers get updates to the protocol documentation.

A Successful Partnership: Microsoft Open Protocols and Aqua Connect

Aqua Connect ultimately decided to approach Microsoft to license the RDP protocol patents. Aqua Connect used the protocol documentation that Microsoft had made publicly available on its developer website ( and further took advantage of access Microsoft provided to its Interop Lab facilities and key Microsoft RDP engineers. Because the implementation of any complex protocol on a completely different OS environment rarely goes smoothly, and the documentation was written with a Windows-environment in mind, the test lab and communication with Microsoft developers was vital to the ultimate success of the Aqua Connect Terminal Server product.

“The most interesting thing for us was that the Microsoft Open Protocols team went above and beyond what we had asked for with the documentation,” said Joseph Cohen, Chief Technology Officer of Aqua Connect. “Our needs related to a Macintosh terminal server were unique, and the process of working with the Open Protocols team went faster and was easier than we had expected. They genuinely expressed a desire to communicate all of the RDP protocol information and related technologies to other companies, like Aqua Connect.”

Ultimately, by choosing to work with Microsoft and the Open Protocols Team, Aqua Connect estimates a savings of more than twice the amount of development time they would have spent implementing their own version of RDP for the Aqua Connect Terminal Server. Additionally, Microsoft’s Open Protocol patent licensing allowed them to choose the licensing model that best met their corporate objectives.