NDG Linux Essentials 2.21 | Open Source Software and Licensing Module 4 | Chapter 04 Exam Answers

NDG Linux Essentials 2.21 | Open Source Software and Licensing Module 4 | Chapter 04 Exam Answers Full 100% 2023 and 2024

These are questions of Cisco NDG Linux Essentials 2.21 Open Source Software and Licensing Chapter 04 Exam Answers full 100% with the latest version and updated in 2023 and 2024. All answers are verified by experts with explanations.

  1. Linux source code is available to:

    •  Employees of the FBI, CIA and NSA with top secret clearance
    • Only employees of the Linux Foundation
    • Only university researchers with a government grant
    • Anyone who has the knowledge needed to access it
      Answers Explanation & Hint:

      The Linux source code is publicly available for anyone to access. It is released under the GNU General Public License (GPL), which allows users to view, modify, and distribute the source code freely. This means that anyone with the necessary knowledge and skills can access and work with the Linux source code, regardless of their affiliation with government agencies, organizations, or foundations.

      It’s important to note that while the Linux source code is open and accessible to the public, certain organizations and entities might have specific agreements or contracts with the Linux Foundation or other entities to support and maintain Linux or to receive additional services related to the Linux operating system. However, these agreements would pertain to support and services rather than exclusive access to the source code itself.

  2. Source code refers to:

    • The interface that software uses to talk to the kernel
    • The version of a program that the computer runs on the CPU
    • The license that dictates how you may use and share the software
    • A human-readable version of computer software
    • Answers Explanation & Hint:

      Source code refers to a human-readable version of computer software. It is the code written by developers in a high-level programming language before it is compiled or interpreted into machine code that the computer can execute. This human-readable code is used to create software applications and defines how the program behaves and functions.

  3. Open source means:
    (choose two)

    • You must share your changes
    • You must support the software you share
    • You can view the software’s source code
    • You can modify the software’s source code
    • You cannot charge anything for the software
    • Answers Explanation & Hint:

      Open source software allows users to access and examine the source code, and it permits them to make changes and modifications to the code as needed. This fosters a collaborative and transparent development environment. However, open source does not necessarily imply that you cannot charge for the software. Many open-source projects allow for both free and commercial use, but they may have specific licensing conditions that determine how the software can be used and distributed.

  4. A license where you don’t have access to the source code is called:

    • Closed source
    • Impaired source
    • Sourceless
    • Open source
    • Answers Explanation & Hint:

      A license where you don’t have access to the source code is called “Closed source.” In closed-source software, the source code is kept proprietary, and users only receive the compiled or executable version of the software. This restricts users from viewing, modifying, or distributing the underlying source code of the software.

  5. Open source licenses differ, but generally agree that:
    (choose two)

    • You should have access to the source code of software
    • You are not allowed to sell the software
    • You must redistribute your changes
    • You should be able modify the software as you wish
    • Answers Explanation & Hint:

      Open source licenses promote transparency and collaboration, allowing users to access and view the source code of the software. Additionally, these licenses usually grant users the freedom to modify the software to suit their needs or preferences.

      However, open source licenses do not typically impose restrictions on selling the software. Many open source licenses, such as the GNU General Public License (GPL), allow users to distribute modified versions of the software, but they may have specific conditions for how these modifications should be licensed and redistributed. Some open source licenses, like the Apache License or the MIT License, do not mandate that modifications must be shared when the software is redistributed.

  6. Richard Stallman is associated with:

    • The Apache foundation
    • Microsoft
    • The Free Software Foundation
    • BSD Unix
    • The Open Source Initiative
    • Answers Explanation & Hint:

      Richard Stallman is associated with The Free Software Foundation (FSF). He is a prominent software freedom activist and a computer programmer known for founding the FSF in 1985 and for initiating the GNU (GNU’s Not Unix) project. He is a strong advocate for free software, which promotes users’ freedom to view, modify, and share software with others. Stallman is often considered the father of the free software movement.

  7. A copyleft provision in a software license means:

    • If you redistribute the software, you must distribute the source to any changes you make
    • You must provide free copies of the software if you use it
    • You give up your copyright to the software
    • You may not link against third party closed source software
    • You must provide support for your modifications
    • Explanation & Hint:

      A copyleft provision in a software license typically means that if you redistribute the software, especially if it has been modified, you must also distribute the source code to any changes you make under the same license terms as the original software. This is the key characteristic of copyleft licenses, such as those found in the GNU General Public License (GPL).

      To clarify the other options:

      • You must provide free copies of the software if you use it: This is not necessarily required by copyleft licenses. What is required is that if you distribute the software (whether modified or not), the recipient must also receive the same freedoms you did, including access to the source code under the same license terms.
      • You give up your copyright to the software: This is not accurate. Copyleft licenses do not require copyright holders to give up their copyright. Rather, they are allowed to retain copyright but must license the software in a way that preserves certain freedoms for users and developers.
      • You may not link against third party closed source software: This is not universally true for all copyleft licenses but is a concern with some strong copyleft licenses like the GPL. These licenses may have restrictions on how the software can be combined with non-free or closed-source software.
      • You must provide support for your modifications: Copyleft licenses do not require you to provide support for the software you distribute, whether modified or not. The obligation is limited to sharing the source code and maintaining the license conditions.

      The core principle of a copyleft license is to ensure that the freedoms to use, modify, and share the software are preserved in all versions of the software, and this is primarily enforced through the requirement to distribute modifications under the same license terms.

  8. The largest difference between the GPLv2 and BSD licenses is:

    • Nothing, they are virtually identical
    • Only BSD allows commercial use
    • BSD has no copyleft provision
    • GPLv2 requires assigning copyright to the FSF
    • GPLv2 is not approved by the OSI
    • Explanation & Hint:

      The largest difference between the GPLv2 (GNU General Public License version 2) and BSD licenses is that BSD has no copyleft provision. Here’s a breakdown of the options you’ve mentioned and their accuracies:

      1. Nothing, they are virtually identical: This is incorrect. The GPLv2 and BSD licenses differ significantly in their core principles, particularly around the requirements related to redistribution and modification.
      2. Only BSD allows commercial use: This is not true. Both the GPLv2 and BSD licenses allow commercial use. The main difference is how the software can be distributed and whether derivative works need to also be open source (as required by GPLv2 due to its copyleft provision).
      3. BSD has no copyleft provision: This is correct. BSD licenses are permissive and do not require redistributions of modified software to be under the same license. They allow modified versions to be distributed under different, even proprietary, terms.
      4. GPLv2 requires assigning copyright to the FSF: This is not a requirement of the GPLv2 itself. Some projects, particularly those managed by the Free Software Foundation (FSF), may require copyright assignment to the FSF, but this is not a requirement of the GPLv2 license per se.
      5. GPLv2 is not approved by the OSI: This is incorrect. The GPLv2 is indeed approved by the Open Source Initiative (OSI). It fully meets the Open Source Definition.

      The key distinction between these licenses lies in their approach to the distribution of modified software. GPLv2’s copyleft requires that the same freedoms granted by the original license must be preserved in distributed derivatives. BSD licenses, by contrast, do not have this requirement, allowing derivatives to be released under different, potentially proprietary, terms.

  9. The Free Software Foundation believes that:
    (choose two)

    • People should write software with no expectation of making money
    • Software should not have copyright
    • Software should be free to share
    • No money should ever change hands
    • Software should be free to modify
    • Explanation & Hint:

      The Free Software Foundation (FSF) promotes several core beliefs about software and its use, distribution, and modification. Among the options you’ve listed, the two that align most closely with FSF principles are:

      1. Software should be free to share: The FSF emphasizes the freedom to run, copy, distribute, study, change, and improve software. This principle is foundational to their advocacy of free software, where “free” refers to freedom rather than price. The FSF believes that users should have the liberty to share software with others.
      2. Software should be free to modify: This is another central tenet of the FSF’s philosophy. They argue that the freedom to modify software and to distribute your modifications to others is crucial, ensuring that the software can be adapted to meet the changing needs of users and communities.

      The other options listed do not accurately represent the FSF’s beliefs:

      • People should write software with no expectation of making money: This is incorrect. The FSF does not oppose the idea of earning money from software. In fact, they support various business models that involve selling services related to free software, such as support and customization.
      • Software should not have copyright: This is also incorrect. The FSF actually uses copyright law to enforce the terms of licenses like the GPL, which aim to ensure that software freedoms are legally preserved.
      • No money should ever change hands: This is not a principle of the FSF. They acknowledge that money can be involved in the process of creating, distributing, or supporting software. The focus is on the freedoms associated with the software, not the absence of monetary transactions.

  10. Which of the following licenses was made by the FSF?

    • GPLv3
    • BSD
    • MIT
    • Creative Commons
    • Apache
    • Explanation & Hint:

      The license that was made by the Free Software Foundation (FSF) among the options you’ve provided is GPLv3 (GNU General Public License version 3). This license is a continuation of the GNU GPL, which was originally created by the FSF to protect the freedom to share and change all versions of a program—to ensure it remains free software for all its users.

      The other licenses listed have different origins:

      • BSD: BSD licenses originate from the University of California, Berkeley, and are associated with the Berkeley Software Distribution, a Unix operating system derivative.
      • MIT: The MIT license is named after the Massachusetts Institute of Technology, where it was originally used for software projects there.
      • Creative Commons: Creative Commons is a non-profit organization that provides a variety of licenses for creative works, not specifically software.
      • Apache: The Apache License is provided by the Apache Software Foundation for use with projects managed by them.

      GPLv3 is the only one in your list that was directly created by the Free Software Foundation.

  11. A permissive free software license:
    (choose two)

    • Requires you share software changes but not binaries
    • Means you can use the software for anything you want
    • Does not allow the software to be locked to certain hardware
    • Places no restrictions on sharing modifications
    • Places the software in the public domain
    • Explanation & Hint:

      A permissive free software license typically has fewer restrictions compared to copyleft licenses, allowing for more freedom in how the software can be used, modified, and distributed. From the options you’ve listed, the two that align with the nature of permissive licenses are:

      1. Means you can use the software for anything you want: Permissive licenses typically allow the software to be used for any purpose, including commercial and private uses, without significant restrictions imposed by the license itself.
      2. Places no restrictions on sharing modifications: Permissive licenses generally allow modifications to be shared without the requirement to also share the modifications under the same license. This means that modified software can potentially be distributed under a different or even proprietary license.

      The other options do not accurately reflect the characteristics of permissive licenses:

      • Requires you share software changes but not binaries: This description is more aligned with copyleft licenses, which often require that if you distribute modified software, you must also make the source code available under the same licensing terms.
      • Does not allow the software to be locked to certain hardware: License terms specifically prohibiting or allowing hardware restrictions are not typically a focus of permissive licenses; rather, this issue might arise in the context of other types of licenses or software agreements.
      • Places the software in the public domain: Placing software in the public domain is different from licensing it under a permissive license. Public domain involves relinquishing all copyright claims, making the work freely available to the public without any copyright restrictions, whereas permissive licenses still maintain copyright but with minimal restrictions on use and redistribution.

  12. Linux is distributed under which license?

    • GPLv2
    • BSD
    • MIT
    • Linux Foundation
    • GPLv3
    • Explanation & Hint:

      Linux, specifically the Linux kernel, is distributed under the GPLv2 (GNU General Public License version 2). This is a copyleft license created by the Free Software Foundation, which means that derived works must also be distributed under the same license terms. The choice of GPLv2 ensures that any modifications or distributed versions of the Linux kernel remain open-source, sharing the same freedoms as the original.

      The other licenses listed are not used for the Linux kernel:

      • BSD and MIT are more permissive licenses that do not require derivatives to be open-source.
      • Linux Foundation is not a software license; it is an organization that supports the development of Linux and related projects.
      • GPLv3 is a later version of the GPL license, which includes additional terms and conditions (like improved protection against patent aggression), but Linux continues to use GPLv2 primarily due to the preference of Linus Torvalds, the creator of Linux, who has chosen not to transition the kernel to GPLv3.

  13. Who founded the Open Source Initiative?
    (choose two)

    • Eric Raymond
    • Bruce Perens
    • Richard Stallman
    • Linus Torvalds
    • University of California at Berkeley
    • Explanation & Hint:

      The Open Source Initiative (OSI) was founded by Eric Raymond and Bruce Perens. These two individuals played pivotal roles in advocating for and defining open-source software principles, distinguishing the movement from the free software movement, which was championed by Richard Stallman.

      Here’s a bit about the other options:

      • Richard Stallman is well-known for founding the Free Software Foundation and initiating the free software movement, which has a slightly different philosophy compared to open-source software, focusing more on the ethical and moral aspects of software freedom.
      • Linus Torvalds is famous for developing the Linux kernel but is not a founder of the OSI. He is more directly associated with the practical development of open-source software rather than the foundational or advocacy aspects of the open-source movement.
      • University of California at Berkeley is linked to the development of the BSD licenses and had significant contributions to early Unix-based operating systems and software, but it did not found the OSI.

      Thus, the correct choices are Eric Raymond and Bruce Perens.

  14. A generic term for Open Source and Free Software is:

    • SLOFF
    • Libre Software
    • OS/FS
    • FLOSS
    • GPL
    • Explanation & Hint:

      A generic term that encompasses both Open Source and Free Software is FLOSS, which stands for Free/Libre and Open Source Software. This term is commonly used to refer inclusively to both movements without bias towards one philosophy or the other. It emphasizes the shared goals of both movements while respecting the distinct principles they uphold.

      Here’s a brief look at the other options:

      • SLOFF: This is not a recognized acronym in the context of software licensing or movements.
      • Libre Software: While “Libre Software” is a term used to emphasize the freedom aspect of software, particularly in non-English speaking countries to avoid the ambiguity of the English word “free,” it is not as universally used as FLOSS to refer to both Open Source and Free Software.
      • OS/FS: This could be seen as an abbreviation for Open Source/Free Software, but it is not a widely recognized or standard term in the community.
      • GPL: Stands for the GNU General Public License, which is a specific type of free software license created by the Free Software Foundation, not a generic term for Open Source and Free Software.

      Therefore, the best choice from the given options is FLOSS.

  15. Which are examples of permissive software licenses?
    (choose two)

    • MIT
    • BSD
    • GPLv
    • LGPLv3
    • GPLv3
    • Explanation & Hint:

      Permissive software licenses are those that impose minimal restrictions on how software can be used, modified, and redistributed. Among the options you provided, the two that are examples of permissive software licenses are:

      1. MIT: The MIT license is a very popular permissive license. It allows the software to be used for any purpose, including commercial development, and only requires that the license and copyright notice appear in all copies of the software. It does not require derivative works to be distributed under the same license.
      2. BSD: The BSD licenses, including the original BSD license and its derivatives like the 2-clause and 3-clause BSD licenses, are also permissive. They allow the software to be used freely for any purpose and have minimal requirements regarding the redistribution of source code. They typically require only the preservation of the copyright notice and disclaimer.

      The other options are not permissive licenses:

      • GPLv3 and LGPLv3: These are both examples of copyleft licenses issued by the Free Software Foundation. The General Public License (GPL) version 3 requires that derivatives of licensed software also be distributed under the GPL, a requirement that does not align with permissive licensing. The Lesser General Public License (LGPL) version 3 allows linking with non-GPL software but still imposes copyleft conditions on the use of the licensed software itself and any modifications to it.

  16. What does it mean when a work is placed in the public domain?

    • The work was done by a government agency
    • The author has relinquished the copyright on the work
    • You must redistribute changes to the software
    • The author has died
    • You may not use the work for commercial purposes
    • Explanation & Hint:

      When a work is placed in the public domain, it means that the author has relinquished the copyright on the work, or the copyright has expired due to other reasons such as the passage of time. This allows anyone to use, modify, copy, and distribute the work without any need for permission, and without the restrictions that copyright normally imposes.

      Here’s a clarification of the other statements:

      • The work was done by a government agency: While it is true that in some jurisdictions, like the United States, works created by federal government employees as part of their official duties are automatically in the public domain, this is not universally applicable and not the defining characteristic of public domain works.
      • You must redistribute changes to the software: This condition is associated with certain open source licenses (particularly copyleft licenses), not with works in the public domain. Public domain works can be modified and redistributed without any obligation to share the changes.
      • The author has died: The death of the author is one of the factors that can lead to a work entering the public domain, but it is not immediate. In most countries, copyright lasts for a certain number of years after the author’s death (commonly 70 years), after which the work enters the public domain.
      • You may not use the work for commercial purposes: This is incorrect with respect to public domain works. Public domain status means there are no restrictions on the use of the work, including commercial use. Anyone can use public domain works for any purpose.

      Thus, the correct interpretation of a work being in the public domain is that the copyright holder has relinquished their rights to the work, making it freely available for public use without restrictions.

  17. Creative Commons licenses allow you to:
    (choose three)

    • Allow or disallow commercial use
    • Specify whether or not people may distribute changes
    • Specify whether or not changes must be shared
    • Receive royalties on the use of the work
    • Get a veto on where the work is used
    • Explanation & Hint:

      Creative Commons licenses are designed to provide a flexible range of protections and freedoms for authors, artists, and educators to legally share their knowledge and creativity. Among the options you listed, the following three are functionalities that can be specified by Creative Commons licenses:

      1. Allow or disallow commercial use: Creative Commons licenses can include a “NonCommercial” (NC) clause, which prohibits the use of the work for commercial purposes unless the user obtains further permission. This allows the original creator to control whether their work can be used in commercial settings.
      2. Specify whether or not people may distribute changes: Some Creative Commons licenses include a “NoDerivatives” (ND) clause, which disallows the distribution of modified versions of the work. This means that others can use the original work as is, but cannot share changes or adaptations they make.
      3. Specify whether or not changes must be shared: Creative Commons also offers licenses with a “ShareAlike” (SA) clause. This clause requires that any adaptations or modifications made to the original work must be shared under the same or a compatible license, which ensures that derivatives are also available for free use under similar conditions as the original.

      The other options are not functions or features of Creative Commons licenses:

      • Receive royalties on the use of the work: Creative Commons licenses do not include provisions for royalties. While they can restrict commercial use, they do not provide a mechanism for collecting royalties. The creator can negotiate separate agreements for commercial uses that are otherwise restricted by the license.
      • Get a veto on where the work is used: Creative Commons licenses do not provide a mechanism for vetoing specific uses or locations where the work can be used. Once the work is licensed under Creative Commons, it can be used by anyone in accordance with the terms of the license, without the creator having the right to veto specific uses.

      These three correct responses highlight how Creative Commons licenses help creators manage how their work is used and shared while promoting openness and creativity.

  18. If a podcast is licensed under the CC BY-ND license, you may:
    (choose two)

    • Share it as long as you give credit to the author
    • Post it to your website
    • Sell it as part of a compilation
    • Add ads to it and post it to your website.
    • Use an interview or song from it for your own podcast
    • Explanation & Hint:

      When a podcast is licensed under the Creative Commons Attribution-NoDerivatives (CC BY-ND) license, it allows certain uses as long as the original work is not altered. Here are the appropriate actions from your list based on this license:

      1. Share it as long as you give credit to the author: This is correct. The “BY” part of the CC BY-ND license requires that you give appropriate credit to the creator, provide a link to the license, and indicate if changes were made. You can do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
      2. Post it to your website: This is also correct. You are allowed to share the podcast by posting it on your website as long as you do not alter the original podcast in any way and you give appropriate credit as specified by the license.

      The other options are not permissible under the CC BY-ND license:

      • Sell it as part of a compilation: While you might interpret selling it as part of a compilation as a form of sharing, this could be problematic under the ND clause if the compilation implies that the podcast was altered or remixed. Moreover, how the compilation is marketed or used commercially might influence this interpretation, so caution is advised.
      • Add ads to it and post it to your website: Adding ads to the podcast would likely constitute a modification, which is prohibited under the “NoDerivatives” (ND) clause of the license.
      • Use an interview or song from it for your own podcast: Extracting parts of the podcast to use in your own podcast would be considered creating a derivative work, which is explicitly prohibited under the ND clause of the license.

      Therefore, the allowed actions under the CC BY-ND license are sharing the podcast with appropriate credit and posting it unaltered to your website.

  19. How can you make money from open source software?
    (choose three)

    • Unlock premium features for people that pay
    • Charge a yearly fee for the right to use the software
    • Sell hardware that’s built to work with the software
    • Take payments for fixing bugs
    • Provide paid consulting services for users
    • Explanation & Hint:

      Making money from open source software can be achieved through various business models that leverage the open nature of the software while providing value-added services or enhancements. Here are three viable options from your list:

      1. Unlock premium features for people that pay: This model, often referred to as “freemium” or “open core,” involves offering the basic version of the software for free, while charging for premium features that offer additional functionality. This approach allows anyone to use and benefit from the open source version while providing paid options for more advanced or enterprise-oriented features.
      2. Sell hardware that’s built to work with the software: This is a common model especially in the technology and IoT (Internet of Things) sectors, where companies develop open source software to drive hardware sales. The software helps to create an ecosystem around the hardware, making the hardware more valuable and sometimes necessary for those using the software.
      3. Provide paid consulting services for users: Many companies and individuals make money from open source software by offering expert consulting services. These services can include customization, training, integration, or even feature development, which are particularly appealing to business users who rely on the software for critical operations but need additional expertise to tailor the software to their needs.

      The other options listed are generally not aligned with open source principles:

      • Charge a yearly fee for the right to use the software: This approach conflicts with the foundational principles of open source software, which allow the software to be freely used, modified, and distributed. Charging for the right to use the software itself would likely violate the terms of most open source licenses.
      • Take payments for fixing bugs: While this might sound viable, it’s typically not presented as charging for bug fixes directly but rather as part of broader support contracts or consulting services. Directly charging to fix bugs in the open source project itself could be seen as contrary to the spirit of open source, where community contributions towards bug fixes are encouraged. However, offering a paid priority bug fixing service within a support or maintenance contract is indeed a practical approach in many business models.

      Thus, unlocking premium features, selling compatible hardware, and providing paid consulting services are effective strategies to monetize open source software while adhering to open source principles.

  20. The difference between the GPL and LGPL licenses are:

    • LGPL allows you to distribute the software in binary-only form
    • LGPL is shorter than GPL
    • LGPL ensures that all variants of the original GPL program has the same freedom of use as the original
    • LGPL was made by the OSI while GPL was made by the FSF
    • LGPL applies to web services
    • Explanation & Hint:

      The difference between the GPL (General Public License) and LGPL (Lesser General Public License) mainly revolves around how they manage linking and distribution of software, especially in relation to libraries. Here’s a breakdown of the options you’ve provided, with clarifications:

      1. LGPL allows you to distribute the software in binary-only form: This statement is somewhat misleading. Both GPL and LGPL allow the distribution of software in binary form, but the key difference lies in the requirements when distributing. LGPL allows you to link the LGPL-covered software (typically libraries) with proprietary software without requiring the proprietary software to also be released under the LGPL or GPL. However, any modifications to the LGPL-covered software itself still need to be made available under the LGPL.
      2. LGPL is shorter than GPL: This is not a meaningful distinction regarding their legal differences and implications. The actual text length of the licenses does not directly impact their legal or functional distinctions.
      3. LGPL ensures that all variants of the original GPL program has the same freedom of use as the original: This is not accurate. The LGPL was specifically designed to allow the use of free libraries with non-free software, which is not necessarily preserving the same freedoms for all derivatives as the original GPL program. The LGPL is more permissive in allowing derivatives to be combined with non-free software.
      4. LGPL was made by the OSI while GPL was made by the FSF: This is incorrect. Both the GPL and the LGPL were created by the Free Software Foundation (FSF). The Open Source Initiative (OSI) approves licenses that comply with their Open Source Definition, but it does not create these licenses.
      5. LGPL applies to web services: This is not correct. Neither the GPL nor the LGPL have specific provisions that directly address the use of the software in a web services context (often referred to as the “ASP loophole”). This issue is partly addressed by the Affero GPL (AGPL), which requires that the source code be made available to network users.

      Therefore, the main difference between the GPL and LGPL is related to how derivatives and linked software can be distributed, particularly regarding the inclusion of LGPL-licensed components in proprietary software without requiring the proprietary parts to be released under the same or compatible open-source license.

  21. Permissive free software licenses:
    (choose three)

    • Are not approved by the OSI
    • Can allow software to be used inside closed source software
    • Are not approved by the FSF
    • Include the GPLv2 and BSD
    • Don’t have a copyleft provision
    • Explanation & Hint:

      1. Can allow software to be used inside closed source software: This is indeed a defining trait of permissive software licenses. These licenses permit the incorporation of open source software into proprietary software without the requirement to disclose the source code of the proprietary additions. Examples include the MIT License and the BSD licenses.
      2. Are not approved by the FSF: The Free Software Foundation (FSF) does approve many permissive licenses as “free software” licenses because they provide the freedom to use, study, modify, and redistribute the software. However, the FSF prefers copyleft licenses because they ensure that all modified versions of the software remain free as well. While the FSF may not advocate as strongly for permissive licenses as it does for copyleft licenses, it still recognizes many permissive licenses as legitimate free software licenses.
      3. Don’t have a copyleft provision: This is accurate for permissive licenses. Unlike copyleft licenses (e.g., the GPL), permissive licenses do not require that modifications or distributed works also be open source. This lack of a copyleft provision is a key feature of permissive licenses, allowing for greater flexibility in how the software can be used, including in proprietary projects.

      Overall, permissive licenses are recognized by the FSF as being part of the broader category of free software licenses, but they are distinct in not containing copyleft provisions and allowing integration into closed source software.

  22. The Creative Commons version of Public Domain licensing is:

    • NoAttribution-ShareAlike (CC BY-SA)
    • Attribution-NonCommercial (CC BY-NC)
    • No Rights Reserved (CC0)
    • Attribution-NonCommercial-ShareAlike (CC BY-NC-SA)
    • Attribution (CC BY)
    • Explanation & Hint:

      The Creative Commons version of Public Domain licensing is represented by No Rights Reserved (CC0). The CC0 license allows creators to waive all their rights to their work worldwide under copyright law, including all related and neighboring rights, as far as the law allows. This puts the work as close to the public domain as possible, allowing anyone to use the work for any purpose without any restrictions.

      Here’s a brief explanation of the other options, which are not equivalent to public domain:

      • NoAttribution-ShareAlike (CC BY-SA): This does not exist as described. The closest is Attribution-ShareAlike (CC BY-SA), which requires attribution and that derivatives be shared under the same license but is not a public domain license.
      • Attribution-NonCommercial (CC BY-NC): This license allows others to remix, tweak, and build upon the work non-commercially, and although their new works must also acknowledge the creator and be non-commercial, they don’t have to license their derivative works on the same terms.
      • Attribution-NonCommercial-ShareAlike (CC BY-NC-SA): This license lets others remix, tweak, and build upon the work non-commercially, as long as they credit the creator and license their new creations under the identical terms.
      • Attribution (CC BY): This license allows others to distribute, remix, adapt, and build upon the work, even commercially, as long as they credit the creator, providing a link to the license.

      CC0 is the correct answer if you’re looking for the Creative Commons license that most closely aligns with placing a work in the public domain.

  23. Your company makes a hardware firewall that runs a custom Linux kernel. What are your obligations under GPLv2?

    • There are no requirements
    • You must make the source to your kernel available
    • You must make your hardware designs available
    • You must make the source to your custom web interface available
    • You must ensure your custom kernel runs on a regular Intel machine
    • Explanation & Hint:

      If your company makes a hardware firewall that runs a custom Linux kernel, which is distributed under the GNU General Public License version 2 (GPLv2), here are your obligations under this license:

      1. You must make the source to your kernel available: This is correct. GPLv2 requires that if you distribute a modified version of software that is under GPLv2, you must also distribute the source code or make it available to the users of the hardware. This means you need to provide the modifications you’ve made to the Linux kernel source code to anyone who receives the device, either directly or via a written offer.
      2. There are no requirements: This is incorrect. The GPLv2 has specific requirements for distribution, especially regarding the availability of modified source code.
      3. You must make your hardware designs available: This is incorrect. The GPLv2 does not cover hardware designs; it only applies to the software that is licensed under it, such as the Linux kernel in this scenario.
      4. You must make the source to your custom web interface available: This depends on how the web interface interacts with the GPLv2-covered Linux kernel. If the web interface is a separate entity that communicates with the kernel in a way that does not constitute a derivative work (such as through command-line tools, system calls, or network sockets), then it might not need to be released under GPLv2. However, if it is tightly integrated (e.g., includes GPL-covered code or links statically with GPL libraries), then it would be subject to GPLv2 requirements.
      5. You must ensure your custom kernel runs on a regular Intel machine: This is incorrect. The GPLv2 does not impose any requirements about the platforms on which the software must run. It focuses on the availability of source code and the freedom to modify and redistribute the software.

      The primary obligation under GPLv2 for your scenario is to ensure that the source code of the modified Linux kernel is made available to the users of the hardware firewall. This aligns with the GPL’s goal of ensuring freedom to modify and redistribute licensed software.