Cost savings of open source software
in the server room

An informal case study in K-12 education

It is often difficult for people to understand that some of the most secure, reliable, and efficient software in the world is not owned by a company but rather is under an open license. Open source software is software that was developed with the source code freely available to the public. Anyone may download and use the software, and make changes to it as necessary, with the hope that any improvements made by individuals will be committed back to the main source tree so that everyone can benefit from the modifications.

While this may sound like a strange way to develop software, it is surprisingly common and effective. For instance, in May 2003, SourceForge.net (a site that offers free hosting for open source software development projects) was host to 60,000 open source projects with over 600,000 registered developers. Many people who, if asked, could only name two operating systems would be staggered to learn how many free and open source complete operating systems exist in the world (and that there are several free OS's that could run on the very hardware you're reading this web page with).

Although few people in my school division know what Linux is, every one of them uses it indirectly every day. Open source software has a particularly appropriate niche in budget-strapped public education institutions. This document aims to describe the benefits that Harrisonburg City Public Schools has reaped from the deployment of open source software in its server rooms.

While certainly not comprehensive, the list below contains a large sample of the free software products that we employ in HCPS. I have attempted to estimate the cost of replacing these free software installations with commercial products. It should be noted that in some cases my estimations are really just wild guesses as to the cost of various commercial solutions. As a general rule I have tried to estimate on the conservative side. Another thing to note is that commercial solutions for a number of the products below often come bundled as one product, making it very difficult to assign individual replacement costs to the items. For instance, most commercial mail server solutions bundle an SMTP server and an IMAP server together while the open source community's philosophy is to create one product for each discrete function.

Software		Estimated cost of commercial solution
Linux distributions
	Red Hat Linux Linux distribution for i386 (PC) hardware	$150 x 17 =	$2550
	YellowDog Linux Linux distribution for PowerPC (Macintosh) hardware	$130 x 5 =	$650
Web server software
	Apache The most widely used web server on the internet	$500 x 6 =	$3000
	PHP Server-side web scripting language	$700 x 6 =	$4200
	MySQL Structured Query Language database server	$500 x 4 =	$2000
	phpMyAdmin Powerful web-based database administration tool	$100 x 4 =	$400
	DataMiner User-friendly web-based interface for managing database content	$50 x 12 =	$600
	ht://Dig WWW Search Engine Software	$200 x 1 =	$200
	Outreach Project Tool Web-based group project collaboration environment	$500 x 1 =	$500
	Claroline Web-based course management system	$5000 x 1 =	$5000
	Phorum Web-based forum/message board software	$100 x 2 =	$200
	phpWiki Web-based knowledge collaboration tool	$100 x 1 =	$100
Mail server software
	Sendmail Internet standard MTA (Mail Transfer Agent)	$150 x 1 =	$150
	Postfix Mail Transfer Agent	$150 x 1 =	$150
	UW IMAP University of Washington IMAP/POP3 mail server	$150 x 1 =	$150
	OpenLDAP LDAP server for intregrated authentication and directory services	$200 x 2 =	$400
	MailMan Full-featured mailing list manager	$150 x 1 =	$150
	Horde Groupware Web-based email, address book, and calendaring software	$1000 x 2 =	$2000
	eL DAPo Web interface for administering an LDAP directory	$50 x 1 =	$50
	DBmail Database-based email system	$150 x 1 =	$150
	Bogofilter Bayesian (statistical) spam filtering tool	$500 x 1 =	$500
Firewalling/Routing software
	netfilter/iptables Stateful IP filtering system	$1000 x 2 =	$2000
Cross-platform file server software
	Samba File server for Windows clients	$800 x 4 =	$3200
	Netatalk File server for Macintosh clients	$500 x 7 =	$3500
Other network server products
	ISC BIND (Berkeley Internet Name Daemon) Internet standard DNS server	$100 x 9 =	$900
	ISC DHCP Dynamic Host Configuration Protocol server	$100 x 8 =	$800
	WU-FTPD FTP server software	$50 x 3 =	$150
	NTPd Network Time Protocol server for synchronization of computer clocks	$50 x 4 =	$200
	Squid HTTP caching proxy server	$200 x 2 =	$400
	rsync Incremental backup solution	$50 x 12 =	$600
Network management and monitoring
	Snort Powerful network intrusion detection system	$5000 x 1 =	$5000
	ACID (Analysis Console for Intrusion Databases) Web interface for monitoring and querying Snort alert database	Bundled with commercial products
	NISCA (Network Interface Statistics Collection Agent) Monitors traffic on switches and routers	$2000 x 1 =	$2000
	Nagios Monitors servers and routers and notifies me of outages via email	$300 x 1 =	$300
	Ethereal Network analysis and packet sniffing tool	$1000 x 1 =	$1000
	sntop Monitors network connectivity	$30 x 1 =	$30
	LanLord Monitors leases on DHCP servers	Bundled with commercial products
	Webalizer Web server statistics reporting tool	Bundled with commercial products

The list above comprises about $40,000 of (roughly) estimated cost savings in software purchases for HCPS.

The commercial replacement cost of the free software that we currently use is obviously very high. However, if I were forced to deploy commercial solutions for all of the above, you could probably guess that I would trim back what we needed to buy significantly. For instance, if it cost me $1000 per web server for the server OS and web server software, you can bet that I wouldn't be running six web servers in my server room like I am now. Rather, I would cut back and only run one or perhaps two web servers. This makes it apparent that not all of the benefit of open source software deployment in is the form of cost savings; much of the benefit is in terms of capabilities gained. In other words, through the use of free software, I am able to do more than I could if I only had commercial solutions available.

Linux can do a lot with only a little hardware. Here in HCPS we have a number of Linux servers running on hardware that would be inadequate for commercial server solutions such as Windows 2000 or Mac OS X. For instance, the web server that served this web page to you is running on an old, retired PC that has been recycled after its lifetime as a Windows desktop has passed. If I were to use Microsoft's IIS server software or Apple's Mac OS X, I would not have considered using this piece of hardware as a web server, and I would have needed to buy new hardware. By enabling me to reuse otherwise useless hardware, open source operating systems have saved our school division a considerable amount of money in hardware costs.

To provide a very rough figure on these cost savings, I estimate that I am currently running 14 Linux servers with hardware that would be inadequate for doing the same job with a commercial solution. To replace those servers with new hardware could easily cost well over $30,000.

So you're probably thinking, "If open source software saves people so much money, why isn't everyone using it?" Two words: learning curve. For people who are used to point-and-click administration of their servers, open source software is often bewilderingly complex to install and configure. I'll admit that you have to be somewhat of a geek to even try out an open source operating system such as Linux. The learning curve that must be followed by a first-time Linux user can be very time consuming and frustrating. For many, especially in public education, this difficulty constitutes a roadblock to the deployment of open source solutions in their district.

As you have seen from the informal analysis on this page, I (and indeed my school division) owe a huge "thank you" to the thousands of developers and other people involved in open source software projects.