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Open Source Economic Model and Licensing

Meeting Three



  1. The Economic model of Open Source
  2. Copyrights, Patents and Trademarks
    1. RAND - Reasonable And Non Discriminatory
    2. What is Intellectual Property?
  3. Licensing models:
    1. What is the General Public License?
    2. The 4 levels of freedom
    3. Creative Commons
  4. The Open Source Way  


Download: Lecture Slides


July 4th 2006:


I received the following question and here is my answer:


Q1) What does the integrity of the Author's Source Code mean? Does it mean that the original author can prohibit another person (who modified the source code) to distribute the modified version? Or when a person distribute the modified software, he/she must attached the original source code together with the distribution?


A1) The idea behind this is to ensure that the original author's code is made available in the original format to anyone who needs it because it could be that those who took the code from the 1st author could have done changes etc to which the 1st author is not entirely aware of. Hence, if a user uses the modified code and finds an issue with it and approachs the 1st author for help, for example, the 1st author would want to know if the user is using his original code or something modified. In general, the 1st author might not be aware of the changes and improvements done to his code in all circumstances. Hence the need to preserve the integrity of the original author's code.


It is like saying that you bought a new car and then you went to modify it. After the modification, you sold it to a 3rd person. Now that 3rd person has some issue with the car and goes back to the manufacturer of the car. Will the manufacturer agree to fix the issue? In most cases you cannot because the "integrity of the car" is not there anymore. In the case of software, that is less of an issue because you can always get the code of the orginal author.


Q2) Can u explain in more layman terms for the following phases: "License must not be Specific to a Product" & "License must be technology-neutral"? I'm really sorry that I dun understand the explanations written in the presentation slides.


A2) An easy example is something like this. If you bought an audio cd, are you restricted from playing that audio cd on only Sony CD players? If that is the case, they the license that the audio cd came in is specific to a product and not technology neutral. This is what we see in music that has digital rights/restrictons management. In the example I gave about DVDs, if you were to buy a DVD from, say, the US, you can play that on DVD players that allow region 1 only. So, if you had a region 3 DVD player (as what it would be in SIngapore), then you cannot play that DVD. Another example is how some websites need Internet Explorer to be the browser for the site to work well. Why should that be the case? By making that restriction, you have a license to use the contents of that site now not technology neutral and specific to a product (IE in this case).


*Further Questions to the above


Q1.1) For question 1, can I simply say that the licence may restrict such that the person that modify the codes to distribute only as a patch file (w/o the original software) with the patch file source code, so that it can differentiate it from the original? And alternatively, if the licence permit distribution of the modified software as a whole, the licence can require the 'new' software to have different name or versions?

A1.1)Yes, you need to share the original source code but the least you have to do is to point to where it is kept. You are not obligated to put it on a diskette/CD/whatever and ship it to the customer. All you need to provide is a way to get to it either via a postal address, URL, email address or some such manner that allows the end user to retrieve it if they want it. Just because you make it available under the GPL, it does not mean that all customers will actually want it, but the GPL ensures that in the event the customer wants it, they have a way to get it.

Previous - Meeting Three

Next - Meeting Five


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