Making Software

Chapter 15. Quality Wars: Open Source Versus Proprietary Software

Diomidis Spinellis

Talk is cheap. Show me the code.

—Linus Torvalds

When developers compare open source with proprietary software, what should be a civilized debate often degenerates into a flame war. This need not be so, because there is plenty of room for a cool-headed, objective comparison.

Researchers examine the efficacy of open source development processes through various complementary approaches:

• One method involves looking at the quality of the code, its internal quality attributes, such as the density of comments or the use of global variables [Stamelos et al. 2002].

• Another approach involves examining the software’s external quality attributes, which reflect how the software appears to its end users [Kuan 2003].

• Then, instead of the product, one can look at the process and examine measures related to the code’s construction and maintenance, such as the how much code is being added each week or how swiftly bugs are closed [Paulson et al. 2004].

• Another approach involves discussing specific scenarios. For instance, Hoepman and Jacobs [Hoepman and Jacobs 2007] examine the security of open source software by looking at how leaked source code from Windows NT and Diebold voting machines led to attacks and how open source practices lead to cleaner code and allow the use of security-verification tools.

• Finally, a number of arguments are based on plain hand waving. More than a decade ago, Bob Glass [Glass 1999] identified ...