free open source software

IF3250 PROYEK PERANGKAT LUNAKIF3250 PROYEK PERANGKAT LUNAKOPEN SOURCE SOFTWARE

Sem II 2013/2014

Free Software Foundation – FSF(www.fsf.org)

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� The Free Software Foundation (FSF) is a nonprofitorganization with a worldwide mission to promote computer user freedom and to defend the rights of all free software users

IF3250-Proyek Perangkat Lunak (IF-ITB)

� founded in 1985

� principal organizational sponsor of the GNU Project

� the FSF maintains historic articles covering free software philosophy and maintains the Free Software Definition

Free Software - FSF3

� “Free software” means software that respects users' freedom and community.

� Roughly, it means that the users have the freedom to run, copy, distribute, study, change and


to run, copy, distribute, study, change and

improve the software.

� Thus, “free software” is a matter of liberty, not price

� free as in free speech, not as in free beer

Free Software - FSF4

� A program is free software if the program's users have the four essential freedoms:

� The freedom to run the program, for any purpose (freedom 0).

� The freedom to study how the program works, and change it so it does your computing as you wish (freedom 1). Access to the source code is a


your computing as you wish (freedom 1). Access to the source code is a precondition for this.

� The freedom to redistribute copies so you can help your neighbor (freedom 2).

� The freedom to distribute copies of your modified versions to others (freedom 3). By doing this you can give the whole community a chance to benefit from your changes. Access to the source code is a precondition for this.

The GNU Licenses5

� The following licenses are published by the Free Software Foundation:

�GNU General Public License (GPL)

�GNU Lesser General Public License (LGPL)


�GNU Lesser General Public License (LGPL)

�GNU Affero General Public License (AGPL)

�GNU Free Documentation License (FDL)

Open Source Initiative – OSI(opensource.org)

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� The OSI is a global non-profit corporation that supports and promotes the open source movement. � founded in 1998� not a membership oragnization� maintain the Open Source Definition, and a list of licenses that comply with that definition


that comply with that definition

� Open source software is software that can be freely used, changed, and shared (in modified or unmodified form) by anyone.

� Open source software is made by many people, and distributed under licenses that comply with the Open Source Definition.

OSI – Open Source Definition7

1. Free Redistribution

2. Source Code

3. Derived Works

4. Integrity of The Author's Source Code

5. No Discrimination Against Persons or Groups



6. No Discrimination Against Fields of Endeavor

7. Distribution of License

8. License Must Not Be Specific to a Product

9. License Must Not Restrict Other Software

10. License Must Be Technology-Neutral


1. Free Redistribution

The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license shall not require a royalty or other fee for such sale.

2. Source Code


2. Source Code

The program must include source code, and must allow distribution in source code as well as compiled form. Where some form of a product is not distributed with source code, there must be a well-publicized means of obtaining the source code for no more than a reasonable reproduction cost preferably, downloading via the Internet without charge. The source code must be the preferred form in which a programmer would modify the program. Deliberately obfuscated source code is not allowed. Intermediate forms such as the output of a preprocessor or translator are not allowed.


3. Derived Works

The license must allow modifications and derived works, and must allow them to be distributed under the same terms as the license of the original software.

4. Integrity of The Author's Source Code

The license may restrict source-code from being distributed in


The license may restrict source-code from being distributed in modified form only if the license allows the distribution of "patch files" with the source code for the purpose of modifying the program at build time. The license must explicitly permit distribution of software built from modified source code. The license may require derived works to carry a different name or version number from the original software.



The license must not discriminate against any person or group of persons.

6. No Discrimination Against Fields of Endeavor

The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may


The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business, or from being used for genetic research.

7. Distribution of License

The rights attached to the program must apply to all to whom the program is redistributed without the need for execution of an additional license by those parties.


8. License Must Not Be Specific to a Product

The rights attached to the program must not depend on the program's being part of a particular software distribution. If the program is extracted from that distribution and used or distributed within the terms of the program's license, all parties to whom the program is redistributed should have the same rights as those that are granted in conjunction with the original software distribution.


original software distribution.

9. License Must Not Restrict Other Software

The license must not place restrictions on other software that is distributed along with the licensed software. For example, the license must not insist that all other programs distributed on the same medium must be open-source software.

10. License Must Be Technology-Neutral

No provision of the license may be predicated on any individual technology or style of interface.

OSI – Popular Licenses12

� Apache License 2.0

� BSD 3-Clause "New" or "Revised" license

� BSD 2-Clause "Simplified" or "FreeBSD" license

� GNU General Public License (GPL)


� GNU Library or "Lesser" General Public License (LGPL)

� MIT license

� Mozilla Public License 2.0

� Common Development and Distribution License

� Eclipse Public License

GNU GPL13

� This license has two versions that are actively used in many open source communities: � GNU General Public License, version 2.0 (GPLv2)� GNU General Public License, version 3.0 (GPLv3)

� If you have licensed software you've written under the GPL version 2.0, you may wish to relicense your


If you have licensed software you've written under the GPL version 2.0, you may wish to relicense your software using GPL version 3.0.

� Version 1.0 of the GNU General Public License is generally seen as deprecated. � the Perl community still uses GPL version 1.0 or later, � the GPL version 1.0 should not be used for new projects outside of this community

GNU General Public License v3

• Created by Richard Stallman

• Fundamental example of an open-source license.

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GNU GPL

• Highly restrictive.

Jonathan HoodCSE 4000Practical Issues in Software Engineering


if( use_gpl_code ) {

distribute_changes_as_gpl();

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GNU GPL

distribute_changes_as_gpl();distribute_linked_apps_as_gpl_compatible();

}



GNU Lesser General Public License

• Can be linked to by non-GPL compatible software.

Can be distributed with your software...

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GNU LGPL

• Can be distributed with your software...



if( modify_lgpl_program ) {

distribute_changes_as_lgpl();

} else {

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GNU LGPL

distribute_however_you_like();

}



Applying GNU GPL18

� Attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found.

One line to give the program's name and a brief idea of what it does.Copyright (C) <year> <name of author>

This program is free software; you can redistribute it and/or modify it under the terms


This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Copyleft19

� "Copyleft" refers to licenses that allow derivative works but require them to use the same license as the original work.

� For example, if you write some software and release it


For example, if you write some software and release it under the GNU General Public License (a widely-used copyleft license), and then someone else modifies that software and distributes their modified version, the modified version must be licensed under the GNU GPL too — including any new code written specifically to go into the modified version

Non-Copyleft20

� Most copyleft licenses are Open Source, but not all Open Source licenses are copyleft.

� When an Open Source license is not copyleft, that means software released under that license can be used as part of programs distributed under other


used as part of programs distributed under other licenses, including proprietary (non-open-source) licenses. � For example, the BSD license is a non-copyleft Open Source license. Such licenses are usually called either "non-copyleft" or "permissive" open source licenses

Software in the Public Domain21

� "Public domain" is a technical term in copyright law that refers to works not under copyright

� either because they were never in copyright to begin with (for example, works authored by U.S. government employees, on government time and as part of their


employees, on government time and as part of their job, are automatically in the public domain),

� or because their copyright term has finally lapsed and they have "fallen into" the public domain.

Types of Open Source Software( http://www.opensourcebc.com/open-source-software/types)

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� Community Based Open Source Software

� Vendor Based Open Source Software

� Hybrid Open Source Software


Community Based Open Source Software23

� Community based Open Source Software is software that is developed and managed by a community of people.

� Often times, there are key developers in the community, but the community is open for anyone to join.


but the community is open for anyone to join.

� Examples of community-based Open Source Software include: Apache, Netscape and GNU Compiler Collection.

Vendor Based Open Source Software24

� Vendor based, or Commercial, Open Source Software is software that is primarily developed and released by a company.

� Typically, the vendor makes a version of the product available in a community edition that is freely downloadable.


available in a community edition that is freely downloadable.

� The community edition does not come with support and typically has less functionality than their commercial version (often called a Professional or Enterprise version).

� Examples of this type of Open Source software include Talend, SugarCRM, and Jaspersoft.

Hybrid Open Source Software25

� The Hybrid model of Open Source software often evolves from a community based system. This occurs when a company forms around the open source project.

� The company typically sells pre-packaged releases of the software and offers training, support and other services.


services.

� In addition, the company often develops and offers proprietary add-ons or customizations to the to Open Source product.

� Examples of this are Red Hat (selling Linux), HortonWorks (selling Apache Hadoop), and EnterpriseDB (selling PostgreSQL).

Pros: Footprint

• People all over the world look at the same code.

• Potentially huge development teams.

• Broader testing base.

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Pros: Cost

IF a component fits your system:

• Save many development hours

• Small customizations may be easy

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• A lot of testing is done for you



Pros: Documentation

• Open source projects have many developers.

• For them, documentation is a must.

• Bad documentation indicates a bad project.

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Cons: Cost

• OSS may not fit your system!

• Large modifications -> Time Consuming

• Testing is hard -> You introduced bugs!

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• People with expertise are expensive.



Cons: Licensing

• In short, hire a lawyer!

• GPL licenses are complex

• FSF protects OSS with a vengeance.

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• A special case. You want to open source!



Cons: Intellectual Property

• You can still infringe on someone’s patents.

• Patent trolls are real.

• Again, hire a lawyer!

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Cons: Temperamental Community• Make sure you contribute back, at least a little

• This community is full of 'early adopters‘

• They influence people's opinions

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Conclusion

• Open Source Software is a great tool

• It's not a silver bullet!

• Know the licenses, and when they are appropriate.

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• It won't always save you money



References34

� www.fsf.org

� opensource.org

� http://www.opensourcebc.com/open-source-software/types


software/types

free open source software

Documents

free software philosophy

free software foundation

free beerfree software

free redistributionthe

free speech

free redistribution2

source code3

users freedom