Source-available software
Shared source refers to Microsoft’s framework for sharing source code with individuals and organizations. Microsoft’s Shared Source Initiative encompasses a spectrum of technologies and licenses. The majority of Microsoft’s Shared Source offerings are available for download by anyone, while some Shared Source programs are tailored to meet the needs of a specific community. For these programs there are eligibility criteria to be met.
The licenses associated with Microsoft’s Shared Source offerings vary, ranging from licenses that permit viewing of the code for reference purposes only to those that allow modification and redistribution of the source code for either commercial or non-commercial purposes.
Benefits of shared source
Shared source provides a number of benefits to end users that are not present in other proprietary software licenses. Among these is the availability of source code for reference when developing complementary systems. For example, having the source code to significant portions of an operating system aids application developers in maintaining stability and consistency in their own programs.[citation needed] The availability of source code also permits review and auditing from a security perspective, something which some large corporations and governments are now mandating.
Shared source benefits the copyright holder in that much tighter control is kept over the use of their product than open source licenses, which generally include the voluntary abdication of many of the author's rights. From the perspective of companies which are used to developing proprietary software, this is a smaller transition to make, and may be seen as an interim step to full open source disclosure.
Comparison of Open Source and Shared Source
From an end-user and original author perspective, shared source licenses share many of the benefits (and drawbacks) of open source licenses[citation needed]. From a "downstream" developer's standpoint, some of the shared source licenses stop short of the rights granted by an open source license while some of the shared source licenses, such as the Microsoft Permissive License and Microsoft Community License, could be characterized as open source licenses[citation needed]. No Shared Source licenses have yet been certified as "Open Source"[1]
| Shared Source | Open Source | |
|---|---|---|
| Availability | Some Shared Source offerings are restricted to customers or partners in a limited number of countries who meet the criteria[2] while others are available to anyone worldwide. | Available to anyone in any country and of any economic status |
| Benefits to downstream developers | easier integration, stability, consistency | easier integration, stability, consistency |
| Upstream benefits | For many of the Shared Source offerings, anyone may submit code for review to the development community of any program. | Anyone may submit code for review to the development community of any program. |
Notable shared source programs
Microsoft Enterprise Source Licensing Program
Microsoft gives enterprise customers viewing access to some parts of some versions of the Microsoft Windows operating systems. The ESLP license agreement is among the most restrictive of the licenses associated with Shared Source programs, allowing no modifications of the code.
Microsoft Windows Academic Program
The Windows Academic Program provides universities worldwide with concepts, Windows kernel source code, and projects useful for integrating core Windows kernel technologies into teaching and research.
Microsoft Shared Source Common Language Infrastructure
The first widely-distributed shared source program is Shared Source CLI, the shared source implementation of the Common Language Infrastructure. The licensing permits non-commercial modification and distribution of the source code, as long as all distributions include the original license, or one encompassing the original terms [3].
Microsoft Shared Source Common Language Infrastructure is neither free software according to the Free Software Foundation [1], nor OSI-approved open source.
Windows Installer XML (WiX)
WiX is a toolset for advanced Windows developers that builds Windows installation packages from XML source code. The first Microsoft Shared Source offering to be released on SourceForge, the WiX toolset is licensed under the Common Public License (CPL).
ASP.Net AJAX Control Toolkit
The ASP.Net AJAX Control Toolkit is a set of controls and extenders that use AJAX technologies to enable developers to easily improve the client experience on their web sites. The ASP.Net AJAX Control Toolkit,licensed under the Microsoft Permissive license (MS-PL) on CodePlex, Microsoft’s online community development portal for collaborative software development projects.
Notable shared source licenses
Microsoft Permissive License (Ms-PL)
This is the least restrictive of the Microsoft licenses and allows for distribution of derived code for either commercial or non-commercial purposes.
Microsoft Community License (Ms-CL)
This Microsoft license allows for distribution of derived code so long as the modified files retain the Ms-CL. The Ms-CL allows those files in the distribution that do not contain code originally licensed under Ms-CL to be licenses in according to the intellectual property creator’s choosing.
On December 9 2005, blogger and programmer John Cowan submitted this license to the Open Source Initiative for approval. [2] [3] It has not been accepted.
Criticism
Free software enthusiasts see shared source licenses as being equal to proprietary licenses. Free software pioneer Richard Stallman has said that Shared Source is "just another name for a nondisclosure agreement". Prominent open source figure Bruce Perens has described its policies as "look but don't touch—and we control everything". [4]. Two of the Shared Source licenses were interpreted as free software licenses by FSF Europe. However, the distribution of many licenses is considered an attempt to obfuscate the meaning of "Shared Source" and generate support from the free software community. [5]
See also
References
- ^ http://www.eweek.com/article2/0,1895,2007088,00.asp Shared source has been submitted for review to the FSF, but not accepted as Open Source
- ^ http://www.microsoft.com/resources/sharedsource/Initiative/FAQ.mspx, again
- ^ As written in the license, examples of commercial purposes would be running business operations, licensing, leasing, or selling the Software, or distributing the Software for use with commercial products
External links
- Microsoft Shared Source Initiative Home Page
- Microsoft Shared Source Basics
- List of Microsoft Shared Source Licensing Programs
- Video interview with Jon Rosenberg, Director of Shared Source Programs at Microsoft
- "Opening Windows, Just a Little". Wired News. Retrieved August 31.
{{cite web}}: Check date values in:|accessdate=(help); Unknown parameter|accessyear=ignored (|access-date=suggested) (help) - "Stallman takes Gates to task over GPL". ZDNet. Retrieved October 17.
{{cite web}}: Check date values in:|accessdate=(help); Unknown parameter|accessyear=ignored (|access-date=suggested) (help) - "On 'Shared-Source' by Michael Tiemann". Open Source Initiative. Retrieved October 17.
{{cite web}}: Check date values in:|accessdate=(help); Unknown parameter|accessyear=ignored (|access-date=suggested) (help) - GNU's List of Non-Free Licenses
- CodePlex