Open source developers porting Microsoft's Indigo and Avalon subsystems for Windows to Linux or Unix will have to go through Microsoft before getting their hands on Windows APIs and protocols.
Microsoft has confirmed developers planning to clone Indigo or Avalon will have to first engage in talks on licensing the company's Intellectual Property (IP).
The policy is likely to kill budding interest from the open source community in further extending aspects of the Windows and .NET architectures to Linux and Unix.
The company came clean after developers who'd cloned other elements of Windows under the Mono Project said they are turning their attention to Indigo, the web services communications platform, and the Avalon GUI. At the time, Microsoft suggested developers could hit a licensing snag as it has so-far not been approached to discuss licensing of Indigo or Avalon APIs.
Mono has worked by implementing elements of Microsoft's .NET Framework made available by Microsoft as standards through the European Computer Manufacturers' Association (ECMA) and the International Organization for Standards (ISO). Mono built implementations of Visual C# .NET, Visual Basic .NET, ASP.NET and ADO.NET, along with open source, Unix and Gnome libraries.
Microsoft submitted its then-new Common Language Infrastructure (CLI) and Visual C# .NET languages for standardization in 2000, it said, to help standardize key technologies for greater interoperability between computing environments.
At the time, Microsoft said the submission to ECMA would: "Help companies leverage existing knowledge and current investments in software development infrastructure to build the next-generation internet."
The suspicion was, though, Microsoft was simply using standards to help quickly seed the market, especially the academic community, with these newer technologies - technologies that are regarded as vital to Microsoft's future direction.
However, Microsoft regards Indigo, and Avalon, as features that will be important to Longhorn, Windows XP and Windows Server Release 2, and which it should retain control of.
Developers who connect to Indigo using implementations of the Microsoft and IBM authored WS- specifications, currently navigating the OASIS and W3C standards processes, though, are in the clear, and do not need to approach Microsoft on licensing of technology used in the WS- specifications.
"If someone wanted to build an implementation of the WS- protocols that could talk to Indigo, they can use the public specs to build their own implementation. If however, someone wanted to clone Avalon or Indigo from top to bottom (that is, from APIs down to protocols) they'll probably want to approach Microsoft about licensing," a Microsoft spokeswoman told The Register.
Separately, Microsoft has confirmed all components of its planned application lifecycle management (ALM) suite - Visual Studio 2005 Team System (VSTS) - will launch with the main Visual Studio 2005 integrated development environment (IDE) during the week of 7 November.
VSTS consists of Visual Studio Edition for Software Architects, Visual Studio for Software Developers, Visual Studio for Software Testers and Visual Studio Team Foundation Server. Also due, will be Visual Studio 2005 Tools for the Microsoft Office System, Visual Studio 2005 Standard, Visual Studio 2005 Professional and .NET Framework 2.0.®