Open and Closed Source Operating System Comparison
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Open and Closed Source Operating System Comparison
Open and Closed Source are the two model of how most software is distributed. The open source code is that exactly, free open-sourced code. Meaning the core functions of the written code are given to a potential developer and that developer is able to manipulate, add to, or change any of the functions of the code. This holds true from the basic core functions or the code to small additional code snippets. FOSS or free and open source software do not typically limit or inhibit the use of the software. However with all of this free distribution, there can be some open sourced software that might have license-based restrictions or redistribution. These restrictions are not overwhelming though. The software can be re-distributed for free, after a developer has modified the code, as long as credit is given to the original manufacturer. FOSS also allows for the code to be modified and then re-compiled, so it can be sold as a complete project. Some examples of this type of re-distribution is Red Hat Inc. Red Hat Inc. takes different pieces of code, pieces it together into a really nice and user friendly interface, and then Red Hat re-distributes this re-compiled code as Red Hat Linux. There have many different flavors and iterations, but as long as Red Hat gives credit in the development to the originally creator, there is no problem with Red Hat re-distributing this OS and sell it for a profit. The code is still free, only Red Hat has complied it together and put an interface on it, so it might be used by everyday users.
With this example of Red Hat, even their re-complied, distributed operating system can be re-modified and then re-distributed again. Fedora Linux and Mandriva Linux are both derivatives of the Red Hat Linux distribution. This situation even has one more different situation than most, as Red Hat Enterprise Linux is itself a derivative of Fedora Linux. Meaning they both support each other as a community project. This is just one example of how one vendor creates and modifies an operating system, then allows a third party vendor to make changes to the software, creating a tertiary operating system that has pieces of code from Red Hat Linux and pieces from Fedora Linux.
A closed source operating system uses constraints on what a developer or hardware manufacturer can manipulate. The manufacturer of the closed operating system designs and compiles the operating system. Once the software is finished and ready for distribution, customers are able to purchase the software and must adhere to the agreement agreed upon once the user has purchased the product. This license agreement that is purchased, is what is most criticized about the closed software model. The criticism states that the customer is not really purchasing the software itself, much like you might purchase a piece of wood from the hardware store that you can take home and use, cut, and change any way you want. But the customer is only purchasing a license to use the software. The customer is unable change, modify, or re-compile the software or operating system. This closed source software model is mostly built and used by companies looking to make a profit. The company writing the software, own all intellectual property of the software or have properly licensed pieces of code, so they are able to sell the software as their own product, and allow you to install and use it.
One of the biggest advantages of the closed source model is that the code that is written is typically considered to be of a higher quality. Although code authors putting together the different open source projects write quality code that works and is proven, a closed piece of software was most likely written with a single purpose in design and the code is compiled to fluidly work together. Whereas the open source model might have had a few different designers writing the code without other pieces of software in mind. Microsoft Windows feels and looks the same across most of its different components. The open source operating system was maybe pieced together without the code writers having the entire picture of the operating system in mind. Maybe one service works or feels one way and a different section of the operating system might behave in a totally different manner. This is not saying that piecing different code snippets together is a bad thing or is a model that doesn’t work, it’s just that the closed source code typically feels like it was designed all together and the functions and behaviors of the operating system are handled the same across the different services or applications of the operating system.

References
Operating Systems: Internals and Design Principles, 7e William Stallings 2012 Pearson Education, Inc.

Operating System Concepts, Eighth Edition Abraham Silberschatz, Peter Baer Galvin, Greg Gagne 2012 John Wiley & Sons Inc.