Dtu 2012_03_15

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Open source – Open source – history, learnings, history, learnings,

when/how when/how

Peter Toft <[email protected]>

Twitter: @petertoftFacebook: peter.a.toft

www.version2.dk/blogs/peter-toft

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QUESTIONQUESTION

● How many of you have one or more piratedpirated software at home?

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QUESTIONQUESTION

● How many of you have one or more piratedpirated software at home?

I don't end in that kindof problems when using

Open Source

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Peter ToftPeter Toft

MsSc EE 1993, PhD 1996, PostDoc 1997

Ex-Chairman of SSLUG

Skåne Sjælland Linux User Group

12 books on Linux – 1800 pages

www.linuxbog.dk

Used Linux daily the last 16 years

Senior specialist at Renesas Mobile (ex-Nokia)

Made 13 Open Source conferences since 1998

Blogger at version2.dk

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Overview of my presentationOverview of my presentation

● History of UNIX/Linux● Do you use Open Source?● What is Open Source ● Software licenses● Linux Development Model● Earning money using Open Source● Data formats – Open vs. Closed● Software patents

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UNIXUNIX

● UNIX invented as a computer operating system between US universities ~30 years ago

– Shared freely

– Extremely open work

– Non commercial

● That changed with HPUX, Solaris – lots of defragmentation :-(

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Free Software FoundationFree Software Foundation

● Founded in 1984 by Richard M Stallman● Target -> The GNU-system

– GNU's Not UNIX

● Free Software– Software must be free

● Compilers, editors etc made

– No Operating System● Software under GPL

– General Public License

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Linus creates LinuxLinus creates LinuxFrom: [email protected] (Linus Benedict Torvalds)

Date: 25 Aug 91 20:57:08 GMT

Hello everybody out there using minix - I’m doing a (free) operating system (just a hobby, won’t be big and professional like gnu) for 386(486) AT clones. This has been brewing since april, and is starting to get ready. I’d like any feedback on things people like/dislike in minix, as my OS resembles it somewhat (same physical layout of the file-system (due to practical reasons) among other things).

I’ve currently ported bash(1.08) and gcc(1.40), and things seem to work. This implies that I’ll get something practical within a few months, and I’d like to know what features most people would want. Any suggestions are welcome, but I won’t promise I’ll implement them

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The UNIX historyThe UNIX history

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The BSD-familyThe BSD-family

Open Source● htttp://www.freebsd.org● http://www.openbsd.org● http://www.netbsd.org

Under BSD-license

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Linux distributionsLinux distributions

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A Linux-distribution containsA Linux-distribution contains

● One or more graphical desktops● Web-browsers

– Firefox

– Chromium

● Productivity programs– LibreOffice (OpenOffice.org)

– Music programs

– Image handling programs

● ~30.000 programs in a modern distro

Free

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Do you use Linux and other Do you use Linux and other Open Source software?Open Source software?

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What in your devices?What in your devices?

● My Samsung TV runs Linux...

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My Phone runs Linux...My Phone runs Linux...

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Next gold rush...Next gold rush...

● The Raspberry Pi– 25 USD

– Runs Linux

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Where we doing not that Where we doing not that

● Tablets● Android seems behind

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The desktopThe desktop

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Linux Linux

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Linux... loads of Open SourceLinux... loads of Open Source

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LAMPLAMP

http://www.version2.dk/artikel/16314

215 million users for FarmVille and MafiaWars

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LAMPLAMP

LinuxApache

MySQL (MariaDB)PHP

Operating system

Apache web server

Database

Scripting

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Using OSS?Using OSS?

● http://dr.dk – Microsoft server 2003– Will switch to Drupal in 2012

● http://tv2.dk – Fedora Linux + Apache● http://berlingske.dk – Debian Linux + Apache● http://dmi.dk - Linux

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Apache runs the InternetApache runs the InternetNetcraft.comIn the March 2012 survey we received responses from Netcraft.comIn the March 2012 survey we received responses from

644,275,754 sites, giving a rise of 31.4M hostnames (5.1%) since last month.644,275,754 sites, giving a rise of 31.4M hostnames (5.1%) since last month.

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Web cache - VarnishWeb cache - Varnish● Made by the dane

Poul-Henning Kamp

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Super computers are LinuxSuper computers are Linux● The top machine has 705024 processor

cores (The K computer in japan)– ~90% of the super computers are running

Linux

– 0.2% Windows :-)

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Cloud + LinuxCloud + Linux● Ooooh yes....

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Also big in DenmarkAlso big in Denmark

● 700.000 customers at One.com – Internet hosting

– Lots of Linux boxes :-)

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Red Hat sells… Linux and Red Hat sells… Linux and serviceservice

Dec 2011: Red Hat's revenue grew to $290 million, a 23 percent increase from a year ago. Of this revenue, $246.5 million came from software subscriptions, a 24 percent increase from the previous year, the company reported. Most of the remaining revenue came from the company's training services.

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CMSCMS

● Joomla● Typo3

– bla. Århus Universitet, Chr. Hansen, Dansk Flygtningehjælp, AOF Danmark, MASSER af mindre sites

● Plone– Ingeniørhøjskolen,Handicap.dk, 65-Ferie

●Drupal

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Support in DanmarkSupport in Danmark● Several companies in .dk

– HP and IBM

– Adapt

– Casalogic

– ConXo

– DoréDevelopment

– Headnet

– Liga Lindist

– Magenta

– MergeIT

– Redpill Linpro

– Fab:IT

OSL.DK

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SambaSamba

● Excellent way to integrate UNIX file servers with Windows clients

– Support for AD

– Provides SMB/CIFS access

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Licenses – and Licenses – and freedom...freedom...

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A software licenseA software license● END USER LICENSE AGREEMENT FOR FULL CONVERT PRODUCT JANUARY 14, 2004 SPECTRAL CORE GMBH LICENSES THIS SOFTWARE PRODUCT TO YOU SUBJECT TO THE TERMS CONTAINED IN THIS END USER

LICENSE AGREEMENT ("EULA"). READ THE TERMS OF THIS EULA CAREFULLY. BY INSTALLING, COPYING OR OTHERWISE USING THE SOFTWARE (AS DEFINED BELOW), YOU AGREE TO BE BOUND BY THE TERMS OF THIS EULA. IF YOU DO NOT AGREE WITH THE TERMS OF THIS EULA, DO NOT INSTALL, COPY OR USE THE SOFTWARE AND IF YOU HAVE PROOF OF PAYMENT, YOU MAY RETURN THE UNUSED SOFTWARE TO THE LOCATION AT WHICH YOU ACQUIRED IT WITHIN THIRTY (30) DAYS FOR A REFUND OF THE LICENSE FEE. NOTICE TO CUSTOMER This EULA is a contract between you (either an individual or an entity) and Spectral Core GmbH ("Spectral Core"), which governs your use of the Spectral Core software product that accompanies this EULA and related software components, which may include associated media, printed materials, and online or electronic documentation. DEFINITIONS This software package contains Full Convert software product. In this EULA, the Full Convert and associated media, printed materials, and online or electronic documentation are collectively referred to as the "Software." The Full Convert enables you to convert data from source to target database. A serial number ("Software License Key") issued to you by Spectral Core is required to use the Software. The term "Number of Licensed Users" means the number one (1), unless you received a Spectral Core License Certificate with this software product, in which case the term "Number of Licensed Users" means the Number of Licensed Users set forth on the Spectral Core License Certificate. WARNING FOR EVALUATION USE The Software can be used for 30 days without purchased Software License Key. In this time, you will have access to limited functionality of the Software. After this time, you must purchase Software License Key or uninstall the product. DURING EVALUATION, THE SOFTWARE IS PROVIDED TO YOU "AS IS" WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE. SPECTRAL CORE BEARS NO LIABILITY FOR ANY DAMAGES RESULTING FROM USE (OR ATTEMPTED USE) OF THE SOFTWARE THROUGH OR AFTER THE EXPIRATION DATE, AND HAS NO DUTY TO PROVIDE SUPPORT OR SOFTWARE UPDATES TO YOU. LICENSE The Software is licensed, not sold. Subject to the terms and limitations of this EULA, Spectral Core hereby grants you a nonexclusive, nontransferable license, without rights to sublicense, to (i) make a number of copies of the Software less than or equal to the Number of Licensed Users for the purpose of installing a single copy of the Software on an equivalent number of personal computers, each of which is running a validly licensed copy of the operating system for which the Software is designed; (ii) use the Software License Key to activate each copy of the Software made in accordance with sub-clause (i); ( iii) have up to the Number of Licensed Users use the Software (in object code form only) solely for your own internal information processing services and computing needs; and (iv) use the documentation accompanying the Software in connection with permitted uses of the Software. If you are an entity, each copy of the Software may be used by one designated individual user only. The total number of designated users may not exceed the Number of Licensed Users. Each copy of the Software may not be used by any other person, whether or not such person is employed by or otherwise associated with your entity. LICENSE LIMITATIONS You may not copy the Software except for a reasonable number of machine-readable copies of the Software for backup or archival purposes and except as expressly permitted in the License section above. You may not share or use concurrently the Software except as expressly permitted in the Limited Shared Use License section above. You may not remove any titles, trademarks or trade names, copyright notices, legends, or other proprietary markings on the Software. You are not granted any rights to any trademarks or service marks of Spectral Core. Spectral Core retains all rights not expressly granted to you. LICENSE AS UPGRADE OF PREVIOUSLY LICENSED PRODUCT If you purchased this Desktop software product as an upgrade at the applicable upgrade price, then you must have previously purchased a prior version of this Desktop software product at the applicable product (not upgrade) price. If you have not purchased a prior version at the applicable product price, then please contact the vendor from whom you purchased the upgrade, or, if you are unable to contact your vendor, Spectral Core, to make payment for the difference between the upgrade price and the product price within thirty (30) days of the date you purchased the upgrade. If you do not make the appropriate payment to your vendor or Spectral Core within thirty (30) days, this EULA will automatically terminate and you must comply with the termination provisions below. LICENSES REQUIRED FOR THIRD-PARTY SOFTWARE The Software allows schema synchronization between two databases. You are responsible for obtaining any licenses necessary to operate any such database system. PROPRIETARY RIGHTS RESERVED BY SPECTRAL CORE Spectral Core retains all right, title, and interest in and to the Software and the Software License Key and in all related copyrights, trade secrets, patents, trademarks, and any other intellectual and industrial property and proprietary rights, including registrations, applications, renewals, and extensions of such rights. RESTRICTIONS You may not (i) sell, lease, license, sublicense, distribute or otherwise transfer in whole or in part the Software or the Software License Key to another party; (ii) provide, disclose, divulge or make available to, or permit use of the Software in whole or in part by, any third party without Spectral Core's prior written consent; (iii) decompile, disassemble, reverse engineer, or otherwise attempt to derive source code from the Software, in whole or in part; (iv) modify or create derivative works based upon the Software; or (v) use the Software to provide network, application hosting or other services to third parties, or otherwise use the Software on a service bureau or hosting basis for your customers. You may not disclose the results of any benchmark test of the Software to any third party without Spectral Core's prior written approval. LIMITED SUPPORT AND SUBSCRIPTION SERVICES Spectral Core may provide limited web-based support services related to the Software for a period of thirty (30) days after the date of purchase. Upon expiration of such 30-day period, Spectral Core will not provide any support services under this EULA. For a period of eighteen (18) months from the date of shipment of the Software, you shall be entitled to receive error corrections and/or fixes to the Software ("Updates"). Updates are generally designated by means of a change of the minor number or number to the right of the decimal point (e.g. Software 5 >> Software 5.0.1 or Software 5.1). Upon expiration of such 18-month period, you shall no longer be entitled to Updates under this EULA. This EULA does not give you any rights to receive any functional enhancements or extensions to the Software developed by Spectral Core at any time in the future that are generally made available for an additional license fee ("Upgrade"). Upgrades are designated by means of a change of the major number or number to the left of the decimal point (e.g. Software 5 >> Software 6). You may purchase support and subscription services separately. If you have purchased Spectral Core support and subscription services with the Software, these services are provided to you under the Support Contract Terms and Conditions posted on Spectral Core's Web site at http://www.Spectral Core.com/support/using/premium.html, and by accepting the terms of this EULA you are accepting these Support Contract Terms and Conditions. Any supplemental software code or related materials that Spectral Core provides to you as part of any support and subscription services are to be considered part of the Software and are subject to the terms and conditions of this EULA. Spectral Core may use any technical information you provide to Spectral Core for any Spectral Core business purposes without restriction, including for product support and development. Spectral Core will not use information in a form that personally identifies you. TERMINATION Spectral Core may terminate this EULA if you fail to comply with any term of this EULA. In the event of termination, you must destroy all copies of the Software and Software License Key. In addition you must remove all copies of the Software from the personal computer(s) on which it is installed. LIMITED WARRANTY Spectral Core warrants that the media, if any, on which the Software is delivered will be free of defects and that the Software will substantially conform to the description contained in the applicable end user documentation, in each case for a period of 90 days after the date of shipment of the Software License Key. EXCEPT FOR THE PRECEDING EXPRESS LIMITED WARRANTY, SPECTRAL CORE MAKES AND YOU RECEIVE NO WARRANTIES ON THE SOFTWARE, EXPRESS, IMPLIED, STATUTORY, OR IN ANY OTHER PROVISION OF THIS EULA OR COMMUNICATION WITH YOU, AND SPECTRAL CORE SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT. LIMITATION OF LIABILITY IN NO EVENT WILL SPECTRAL CORE BE LIABLE FOR ANY LOST PROFITS OR BUSINESS OPPORTUNITIES, LOSS OF USE, BUSINESS INTERRUPTION, LOSS OF DATA, OR ANY OTHER INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES UNDER ANY THEORY OF LIABILITY, WHETHER BASED IN CONTRACT, TORT, NEGLIGENCE, PRODUCT LIABILITY, OR OTHERWISE. THIS LIMITATION SHALL APPLY REGARDLESS OF WHETHER SPECTRAL CORE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SPECTRAL CORE'S LIABILITY UNDER THIS EULA WILL NOT, IN ANY EVENT, EXCEED THE LICENSE FEES, IF ANY, PAID BY YOU TO SPECTRAL CORE FOR THE SOFTWARE LICENSED BY YOU UNDER THIS EULA. GENERAL This EULA is governed by the laws of Switzerland without regard to conflict of law principles. This EULA is the entire agreement between us and supersedes the terms of any purchase orders and any other communications or advertising with respect to the Software. If any provision of this EULA is held invalid, the remainder of this EULA shall continue in full force and effect. This EULA may be modified only by written agreement signed by authorized representatives of you and Spectral Core. CONTACT INFORMATION If you have any questions about this EULA, or if you want to contact Spectral Core for any reason, please direct all correspondence to: Spectral Core GmbH, Mittelurmi, 6442 Gersau, Switzerland or email [email protected]. Spectral Core is a trademark of Spectral Core GmbH.

ACCEPT DECLINE

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QUESTIONQUESTION

What do these EULA say?

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Microsoft EULA win 7Microsoft EULA win 7● You may

– One Copy per Computer. You may install one copy of the software on one computer. That computer is the “licensed computer.”

– b. Licensed Computer. You may use the software on up to two processors on the licensed computer at one time. Unless otherwise provided in these license terms, you may not use the software on any other computer.

– c. Number of Users. Unless otherwise provided in these license terms, only one user may use the software at a time.

● Microsoft may

– repair the software, remove, quarantine or disable any unauthorized changes that may

– interfere with the proper use of the software, including circumvention of the activation or validation functions of the software, or

– check and remove malicious or unauthorized software known to be related to such unauthorized changes

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MS Eula <-> OSSMS Eula <-> OSS

● MS Eula – brugeren gets very limited rights. Microsoft can even detect which software is running on your machine

● Open Source software places the developer and the user as equals

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Open SourceOpen Source● Bruce Perens, Eric Raymond et al defines “The

Open Source Definition” with a basis in“The Debian Free Software Guidelines”

● Eric S. Raymond get huge popularity– Feb 1998

● BIG succes!!

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Understanding the value of Understanding the value of the source codethe source code

The programmer writes source code

Typically english-like text – with syntax

Translate – compile – a source file to a binary program

Most often the binary program cannot be edited

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Compile processCompile process

#include <stdio.h>#include <stdio.h>

int main(void)int main(void){{ printf("Hi DTU - you are cool\n");printf("Hi DTU - you are cool\n");}}

010010101010101001010011110111101001010101010100101001111011110000101010101000101110010100101000001010101010001011100101001010

Save as hello.c on diskSave as hello.c on disk

Run “gcc -o hello hello.c”Run “gcc -o hello hello.c”

Run “hello”Run “hello”

You see “Hi DTU – you are cool”You see “Hi DTU – you are cool”

Run “hello”Run “hello”

Source code is what the programmer

Writes. Did you know that 90-95% of all code is for internal usage

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Open Source is about freedomOpen Source is about freedomhttp://www.opensource.orghttp://www.opensource.org

● 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.

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● 2. Source Code– The program must include source code,

and must allow distribution in source code as well as compiled form.

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● 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.

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● 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

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Open SourceOpen Source

You may copy the program

You can use the program as you like

You can change the source dode of the program and make derived work

You must offer the source code along with the program

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Linux Development ModelLinux Development Model

Fast releases

Peer review of source code

or trail and error

All can participate

Good solutions win

Bad code dies

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Linux Development Model (II)Linux Development Model (II)

Company

User A: Error when hitting F1

User B: Error when hitting F1

User C: Error when hitting F2

Core group

User C: Error when hitting F1 – here are the needed fixes



Linux development model

Traditional company/user

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L1 LinusL4

L3

L1

L2

LinuxKernel

mailing list

2.6.40-ac

2.6.40

2.6.40-ll

Linus GitRepository

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L1 LinusL4

L3

L1

L2

LinuxKernel

mailing list

2.6.40-ac

2.6.40

2.6.40-ll

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L1Linus Git

RepositoryL4

L3

L1

L2

LinuxKernel

mailing list

2.6.40

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L1 CVSL4

L3

L1

L2

project mailing list

or IRC

2.6.40

LxNew C/C++ code

Linus GitRepository

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L1 CVSL4

L3

L1

L2


or IRC

2.6.40

LxNew C/C++ code

Linus GitRepository

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L1 CVSL4

L3

L1

L2


or IRC

2.6.40

Lx

Linus GitRepository

New C/C++ code

New C/C++ code

New C/C++ code

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L1 CVSL4

L3

L1

L2


or IRC

2.6.40

Lx

Linus GitRepository

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The Open Source SocietyThe Open Source Society

● Very short distance between developers and users

● High knowledge level● With Open Source I can get into an open

playing field– Our company relationships don't really matter

● People who love to improve software by suggestions from others

– Very similar to the scientifical method of peer-review

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What drives Open SourceWhat drives Open Source

We got so much – we want to pay back

It is fun to create what others are happy to use

We can get the programs to work exactly like we want to

Freedom to choose

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Can I earn money now?Can I earn money now?

● Consultancy● SLA/support/out-sourcing● Training● Loss-leader swap to Open Source can be

good● Alternative earnings

– Facebook + Google 90-95% of all code

is for internal usage

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Open Source Days 2012Open Source Days 2012Case story: Composite 1Case story: Composite 1

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We win on Open SourceWe win on Open Source

We can choose the software vendor freely

Self-made

Consultants

Service-contracts

We all have the same source code and tools

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Where to compete?Where to compete?

Operating System

Kernel drivers

System libraries

Applications

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Remember this slide?Remember this slide?

● My Samsung TV runs Linux...

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Data formats and theData formats and theproblems for Open Sourceproblems for Open Source

- Patents on software- Patents on software

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Data formatsData formats

● Can you understand me?

● I send “Can you read this?”● You respond “yes I can?”● I respond “Good – now I will tell more”

You Me

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Data formats – now encryptedData formats – now encrypted

● I send “iTunesFormatCXKSJFSJDLSKJL”● You respond “I cannot understand”● I stop

You Me

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Data formats – now encryptedData formats – now encrypted

● You send “MicrosoftFormatCXKSJFSJDLSKJL”

● You respond “I cannot understand”

● Your friend respond “MicrosoftResponseXKDLKLK”

● I quit....

You Me

Your friend

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The Data FormatThe Data Format

● Secret data formats – Word reverse engineered

– Apple

● Open Standards– HTML

– PDF

– ODF

– OOXML ?

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InternettetInternettet

● W3C– Founded by Tim Berners-Lee,

W3C Director and inventor of the World Wide Web

● HTML is an open standard

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WikipediaWikipedia

● Jimmi Wales – founder of wikipedia● 3 fundamental principles of Wikipedia are:

– Focus on becoming an encyklopedia.

– A wiki for all

– Open content under GNU Free Documentation License.

●

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Open StandardsOpen Standardshttp://www.aabenstandard.dk/http://www.aabenstandard.dk/

● An open standard is accessible to everyone free of charge (i.e. there is no discrimination between users, and no payment or other considerations are required as a condition of use of the standard)

● An open standard of necessity remains accessible and free of charge (i.e. owners renounce their options, if indeed such exist, to limit access to the standard at a later date, for example, by committing themselves to openness during the remainder of a possible patent's life)

● An open standard is accessible free of charge and documented in all its details (i.e. all aspects of the standard are transparent and documented, and both access to and use of the documentation is free)

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What do you know about What do you know about software patents?software patents?

I speak as a private personRepresenting the Open

Source developers...

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What will we gain with What will we gain with software patentssoftware patents

Patents are an agreement between sociaty and the inventorThe inventer gets an exclusive right for 20 or 30 years to exploit the ideaWe – the world – gets insight to the ideaDo we get any essential knowledge transfer?

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Patents secures our R&D Patents secures our R&D spendings....spendings....

In USA (~1985) software patents were allowed:

The number of software patents EXPLODED

Among the biggest patent holders the R&D costs decreased relative to sales

Clearly stopped onwards development

James Bessen and Eric Maskin, MIT

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Open Source is against patentsOpen Source is against patents

● The big companies share the marked earnings using patents

● We are mostly “small fish”● No fun being sued....

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Quality of software patentsQuality of software patents

In the US approx 2 hours is spend to review if an idea is “novel”

THIS STINKS!

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Software Software patentspatents

http://opensource.com/law/12/3/how-http://opensource.com/law/12/3/how-patents-hinder-innovation?patents-hinder-innovation?

sc_cid=70160000000UDqHAAWsc_cid=70160000000UDqHAAW

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US patent: WindowingUS patent: Windowing

Windowing: Solve the y2K problem

If year > 30 then year = year + 1900

Else year = year + 2000

Example 86 => 1986 og 00 => 2000

United States Patent by Dickens September 8, 1998

– Search for patent 5,806,063 on http://www.uspto.gov/

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US patent: Windowing (II)US patent: Windowing (II)

Date formatting and sorting for dates spanning the turn of the century

Abstract

Dates stored in symbolic form in a database are reformatted to permit easy manipulation and sorting of date-related information. Each date in M.sub.1 M.sub.2, D.sub.1 D.sub.2, and Y.sub.1 Y.sub.2 format is converted to C.sub.1 C.sub.2, Y.sub.1 Y.sub.2, M.sub.1 M.sub.2, and D.sub.1 D.sub.2 format. To accomplish the conversion, a 10-decade window starting on Y.sub.A Y.sub.B is defined that encompasses all dates in the database. The value of C.sub.1 C.sub.2 is determined by the relative values of Y.sub.1 Y.sub.2 and Y.sub.A Y.sub.B. The reformatted date information is particularly useful when the reformatting is in C.sub.1 C.sub.2 Y.sub.1 Y.sub.2 M.sub.1 M.sub.2 D.sub.1 D.sub.2 format, because sorting by date is accomplished using a pure numerical-value sort.

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A web shopA web shophttp://itpol.dk/sager/swpat/english_videoshophttp://itpol.dk/sager/swpat/english_videoshop

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Questions?Questions?Overview of my presentationOverview of my presentation

● History of UNIX/Linux● Do you use Open Source?● What is Open Source ● Software licenses● Linux Development Model● Earning money using Open Source● Data formats – Open vs. Closed● Software patents

Education

Dtu 2012_03_15