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2.2. Free software conceptsOnce the definitions are given, it is important to stay on at ideas promoted by the free software movement. It's important as well to clear some wrong ideas hawked on these software. This section gives then a various set of elements in favour of the introduction of free software and ends on the real problems remaining to solve. 2.2.1. Free software philosophyIn fact, the philosophy promoted by the free software movement is not that different from the one proposed by the scientific movement till a long time already: to put in common ideas and collective knowledge to allow the progression of the research and the growth of this knowledge. The knowledge of the human genome is one of the examples of such a collaborative work. The computer engineering environement, and especially the software one, seems to have turn away till the last 20 years from these base concepts of the scientific world. It prefers on the contrary to keep the customer captive instead of giving him the informations needed to exploit his computing environement the best he can. That's indeed following such a problem at the begining of the 80's that Richard Stallman, who was doing researches in artificial intelligence at the MIT, decided to create the GNU project. This project is the foundation of the current free software movement. The main ideas promoted by this movement and stated by Richard Stallman himself are :
More over the utopy of these ideas, we can find other reasons which allowed free software to spread so widely today. They are detailed in Section 2.2.2. The free software movement materializes itself also through a community of people. That community, informal meeting of personnalities, is heterogeneous in its contents, actions, ideas, even if all share the same belief in the freedom of the software. That community created for itself the tools needed to its communication : Internet and Usenet. And these communication tools are based of course on a lot of free software to work. Among the outstanding persons of this movement, we can present :
All these personalities are, above all, excellent computer engineers, which allows them to be recognized as major actors of the free software movement. Their human and communication qualities are also strong characteristics of their nature. In any case they aren't considered for their power, but for their knowledge. Of course, the free software community is built of thousands of programmers, whose complete list would be too tedious. All share the will of producing useful work, free, and to be recognized for their technical qualities above all. 2.2.2. The choice of free softwareTo use free software to bring solutions in a computing environment is a choice. First, it is in favour of a plurality of solutions, mainly in the personal computer world which tends to be monopolistic. Then, the choice is made, and that's what is finally important, on the own qualities of free software, which are detailed just below.
Independantly of its qualities, it's possible to give other reasons of various nature, in favor of free software, depending on the type of the person met. 2.2.2.1. Marketing argumentationStudies from IDC bring to light the irresistible rise of Linux as a server operating system. In 1998, Linux is credited with 17% of market share, with an increase of 212%, which is the most important in that domain. The following graphics give the whole market share repartition. This was confirmed in 1999 with a market share climbing to 24% and an ancrease of 93%, always more than four times the increase of the follower. Dataquest estimates on its side that Linux servers will represent, with 1.1 million of units, 14% of the servers sold in 2003. the Net itself produces marketing tools to demonstrate the superiority of free software. Two counters are regularly updated by Netcraft, on web server software, and by IOS Counter for the servers on Internet. Results, reproduced below, show the importance taken by Apache with more than 6 millions of operational sites, crushing the competition, as well as the free operating systems Linux and *BSD which dominate the world of Internet servers. 2.2.2.2. Financial argumentationFinancial arguments also speaks for free software. And first the price to aquire them is low. Low, because it's never zero. Even if you can find it on Internet, you have to consider the costs related to that link. However costs are greatly less expensive than for commercial software. So a RedHat 7.0 Linux distribution, delivered with more than 1200 software packages, costs about 60 USD when you have to pay more than 800 USD to obtain Windows NT server, delivered only with IIS. On the other side, free software don't have the notion of license by user or by supplmentary service. Thus there is no additional cost when you have to increase the use of these software in your entity. That's of course not the case with commercial software whose economical logic is often based on the number of licenses. Free software bring in addition a better mastering of the TCO (Total Cost of Ownership), mentionned so frequently in the massive deployment of personal computers. Thus administration costs are reduced because systems like Linux or FreeBSD, as Unix, are managed completely remotely, either through command line orders (with telnet) or in graphical mode by using X-Window. More over, we benefit from a true multi-users mode, improving these management operations. Always in this domain, it's also possible to do remote management, either through the own hardware capacities (as the Remote Assistant card integrated in most HP NetServers), or by doing a remote connexion (through modem, ISDN adapter or a permanent link) thanks to the native protocol PPP and secure connexion systems as tunneling or ssh. This managemnt could even be realised by an external entity, in outsourcing. At last, the costs due to the hardware themselves could be controled; on one side, if by chance free software don't meet the needs, it's always possible to buy then commercial software solutions to cover the rest. On the other side, solutions based on free software have good performances by nature, and can use hardware platforms which would be considered as obsolete, if installed following the standard criterias of other operating systems or applications. It's so possible to use "old" hardware, mainly to model. It's then possible to invest, with a fine knowledge, when puting the solution in operation, if needed. The power increase may naturaly take place progressively. 2.2.2.3. Technical argumentationThis argumentation was already given in the previous sections. I think nevertheless that some notions may be explained with complementary informations. So concerning the reliability aspects of free software based solutions, it's important to note that it implies an operational running time very high (standard characteristic of Unix systems in general). This is mesured by the command uptime. One of Medasys and HP customers, Saint-Michel Hospital, has a Vectra VL5 acting as router under Linux since more than 300 days. And that's not a isolated case. Respect of standards and norms, as well as the extreme portability of free software assures also to applications developed on these platforms the same qualities. And notably, if after their use, the performances or services brought by free software based architectures were insufficient, it would be easy to migrate to machines offering more performances and capacities of evolution, as the HP 9000 systems, running HP-UX. At last a development plan centered around performances implies a modularity, such as it's possible to resize the system kernel nearest to the capacities of the hardware or to use dynamically loaded modules following the needs. A packages installation may vary from 40 GB for a minimal system up to many GB for a complete distribution. The system linearity allow also the support of multi-processors machines (SMP) (tested up to 32 processors on a Sparc machine). The system modularity allows also to obtain an operational system on a 1.44 MB floppy disk, either to realize a minimal repair environment, or to provide a perfectly operational router. The world of embedded systems shows besides more and more interest for systems such as Linux, because above it's modularity, source availability makes communication with dedicated peripherals easier (acquisition cards, sonde, ...). Entities as CERN or Thomson already use such solutions. 2.2.2.4. Solutions argumentationThat argumentation is probably the most important of all, because it's useless to have free software if it's not to make something useful with it or to offer solutions to demands of entities willing to use it. In which sectors free softawre may bring solutions today ? Well, you have to admit it's in nearly all the sectors of enterprise computing. Historically, Open Source Software were used to realise Internet/Intranet servers, because their growth was following the one of the Net. It's so possible to cover all aspects linked to the Internet, from the Web server ( Apache ), FTP server (Wu-Ftpd), DNS server (Bind), the E-Mail server (Sendmail or PostFix ), the Usenet groups server(INN), the proxy server (IPmasqadm), the firewall (IP-Chains), Virtual Private Network (OpenSSH), the Cache server for the Web ( Squid ) or also the Time server (NTP) or as(LDAP) server, or as content management(Midgard") server ... All these software are available in standard in a Linux distribution. The client computer should be equiped with the software corresponding to the application used (mail reader, news reader, web browser, ...) whatever its operating system. The choice of the client is free, as all these tools respect the standards decreed in the RFCs. The second preferential domain for free software is the file and print server domain. For these services, clients may be multiple: Unix type (use of NFS and KNFS or also Coda, for file sharing and of lpd for print service), Microsoft Windows type (use of SaMBa , which allows also the use of local client printers), Novell type (Use of Mars_nwe) or MacIntosh type (use of NetAtalk). All these software are provided in standard in a Linux distribution and don't need any modification at the client level to work. The other domains where a system such as Linux may bring solutions is the computation one, with support of multiprocessor, linked to the realisation of clusters with multiple nodes with high-speed network interfaces (100 Mbit/s, Gigabit or Myrinet); those of data security with the support of HP NetRaidRem. cards, allowing Raid level of 0, 1, 3, 5, 10, 50, and HotSpare disks, managed by the harware; those of centralized fax server, with a free software like HylaFAX or also as an archive/backup server with HP SureStore DAT or DLT libraries thanks to a commercial software like Arkeia or at last as a database server with free solutions like PostgreSQL,MySQL or commercial like Oracle, to speak only of these three. On the client side, even if it's less highlighted for the moment, possibilities to use solutions based on free or commercial software are numerous. There also the Internet part is the main one, with tools like graphical web browsers (Netscape) or textual (lynx), a lot of graphical mail readers (Kmail, XFMail, ...) or textual (mutt, elm, ...). But you also have the whole panel of indispensable tools for a personal computer today as a PDF reader (Acrobat Reader or xpdf), image manipulation tools (ImageMagick, the Gimp, RealPlayer tools ...), word processors (LyX, LaTeX, SGMLTools, Wordperfect, ...), commercial office suites (ApplixWare, StarOffice), sound management tools (WavTools, eplaymidi, xmcd, ...), CD burning tools (cdrecord, BurnIT, ... with complements as mkisofs, cdparanoia), free and commercial emulators for various systems (Wine, Executor, WABI, DOSEmu, ...), compilers and interpretors for all the languages (C, C++, Pascal, Fortran, Basic, Tcl/Tk, Perl, Python, Ada, Eiffel, Lisp, Scheme, Prolog...), including commercial versions ( PGI, ...), graphical environments (Gnome, KDE, Motif, ...). The evolution of these last tools indicates that the 2000's may be the years where Linux and free software will break through at their turn on the client. I want to mention that this document was realized on an HP Brio BAx equiped only with a Linux distribution, with the help of tools like SGMLTools, Jade and DocBook, which allowed to generate from a single source the formats HTML, Txt, RTF, PostScript, and PDF. 2.2.2.5. Service argumentationThis one was for a long time a blocking point to the expansion of free software in the firms. It's not the case today. Many service providers or hardware manufacturers, like HP, control today these solutions and propose support around them. Other sources of informations are also available, in abundance, through several web sites dedicated to these solutions, specialised mailing-lists, and various Usenet groups, such as for Linux, the international groups under comp.os.linux.* or for the french speaking people under fr.comp.os.linux.*. Concerning competences, more and more young engineers or academics finish their learning cycle being trained to the use of free applications and operating systems. This wealth of competences arrives now on the labour market and will contribute to increase the movement of generalisation of these tools. At last, many firms have internaly ignored competences. In fact, their employees often install this software at home, and have a good mastering, usable when arrives the deployment of the software in their professional structure. 2.2.3. Wrong ideas on free softwareAdvocating free software consists also to mention some generally accepted ideas concerning them and to fight them.
2.2.4. Real problems around free softwareIt would not be honest to negate certain remaining problems linked to free software. Some have begun to disappear, other are inherent to the system, other at last will take time to diappear. The first problem, inherent to the model of free software, is the multiplicity of tools and distributions available. So, if you want to setup a mail server, you have to choose between Sendmail, Exim, PostFix, Qmail, Smail. As well if you want to install Linux, you may choose between the distributions RedHat , SuSE, Slackware, Mandrake, Turbo Linux, Debian. This represents often a problem for the newcomer, but the esperienced user will always prefer to have a large choice he will confront to his particularities and to his experience. As long as an actor respects the rules by freeing his code (it's the case of the rpm and deb formats for example), there is little risk from the comunity point of view. The second problem, inherent also to the free software birth, is the necessity to have strong Unix and Internet competences, to manage such solutions. The power available through these systems is proportional to the competence of their administrators. And that will stay true even with the growth of more and more grahical solutions to manage them. On the other side, you capitalize the investment in time to learn their functions and that doesn't disappear, because you don't have to re-learn eveything from one version to the other. Don't forget that systems you use daily seem to be simple, uniquely because you passed enough time to learn them. For Internet competences, it's a statement of the obvious to say that this investment isn't lost. At last, even with the work of translators to provide informations in french and other languages, a good knowledge in technical english is definitively a plus. The last problem met in the implementation of free software solutions is to suceed in convincing some mnagers to go against the prevailing opinion. The aim of this part is precisely to give all sorts of argumentations to achieve that goal, but you need each time to show conviction to get his way in the end. As soon as these solutions will be adopted by big firms principaly, resistances will disappear. |