Andrew_Tridgell

:''For the three-way bridge in [[Midland, Michigan|Midland]], [[Michigan]], please see [[The Tridge]]''
{{Infobox person
|name=Andrew Tridgell
|image=Andrew Tridgell.jpg
|birth_date={{bda|1967|02|28}}
|occupation=Programmer
|known_for=[[rsync]], [[Samba software|Samba]]
|nationality=Australian
|employer=[[IBM]]
|other_names=Tridge
}}
'''Andrew "Tridge" Tridgell''' (born [[February 28]], [[1967]]) is an [[Australia]]n [[computer programmer]] best known as the author of and contributor to the [[Samba software|Samba]] [[file server]], and co-inventor of the [[rsync]] algorithm.

He is known for his analysis of complex [[Proprietary software|proprietary]] [[protocol (computing)|protocols]] and [[algorithm]]s, to allow compatible [[free software]] implementations.

== Projects ==
Tridgell was a major developer of the Samba software, analysing the [[Server Message Block]] protocol used for [[workgroup]] and network file sharing by [[Microsoft Windows]] products. He developed the [[talloc]] hierarchical memory allocator, originally as part of Samba.

For his PhD thesis, he co-developed [[rsync]], including the rsync algorithm, a highly efficient [[List of file transfer protocols|file transfer]] and [[File synchronization|synchronization]] tool. He also was the original author of [[rzip]], which uses a similar algorithm to rsync.

Tridgell was also a leader in [[hacker|hacking]] the [[TiVo]] to make it work in Australia, which uses the [[PAL]] video format.

In April 2005, Tridgell tried to produce free software (now known as [[SourcePuller]]) that interoperated with the [[BitKeeper]] source code repository. It was a source of controversy and was cited<ref>http://lwn.net/Articles/169178/</ref> as the reason that BitMover revoked the license that allowed [[Linux]] developers free usage of their BitKeeper product. This resulted in a messy public falling-out between Tridgell and [[Linus Torvalds]], in which Tridgell stated that he had never had a BitKeeper license so he couldn't violate it and had acted entirely ethically in analysing and implementing the protocol, something he'd previously done with the Samba protocol. Tridgell's involvement in the project resulted in Linus accusing him of playing dirty tricks with BitKeeper<ref>http://www.theregister.co.uk/2005/04/14/torvalds_attacks_tridgell/</ref>.
The broad extent of Tridgell's analysis started by [[telnet]]ing to a BitKeeper server and typing <code>HELP</code><ref>http://www.groklaw.net/articlebasic.php?story=20050421023821174</ref>, something that, seemingly, no-one else had previously thought to try.
{{Fact|date=September 2007}}

== Academic achievements ==
Attending [[Barker College]] Hornsby, NSW, Tridgell completed his HSC in 1985. Tridgell completed a [[science degree]] with majors in [[applied mathematics]] and [[physics]] at the [[University of Sydney]] in 1988, before moving to [[Canberra]] to complete an [[Honours degree]] at the [[Australian National University]], in which he received first class honours in [[theoretical physics]].

Tridgell completed a [[PhD]] at the Computer Sciences Laboratory of the [[Australian National University]]. His original doctorate work was in the area of [[speech recognition]] but was never completed. His submitted thesis 'Efficient Algorithms for Sorting and Synchronization' was based on his work on the [[rsync]] algorithm.

== Employment ==
Tridgell started his career working for [[Efam Resources]] from 1987 to 1988, designing [[computer modeling|computer models]] of [[financial markets]]. His work led to a product named The Options Analyst, which he marketed and sold for five years.

From 1988 to 1989, Tridgell worked as a software developer for a company named Sonartech Pty Ltd (now Sonartech Atlas), which developed [[sonar]] technologies for Australian [[submarine]]s. He worked on [[Sonar|passive sonar]] technology.

Between 1989 and 1990, Tridgell was employed at the Research School of Biological Sciences in the Australian National University, making computer models of physical and biological events and environments such as bushfire spread and [[population dynamics]].

From 1991 to 1999, Tridgell held various other positions at the Australian National University, such as [[UNIX]] administration, [[satellite]] control, and [[supercomputer]] research. During this period he was seconded to the Cooperative Research Centre for Advanced Computational Systems, where he headed the PIOuS (Parallel Input/Output System) project - later HiDIOS (High-performance Distributed Input/Output System) - for parallel file systems on the Fujitsu AP1000 and AP+ supercomputers. Tridgell also went on to lecture, first as an associate lecturer, and then as a casual lecturer, in the university's Computer Science division. He remains a Visiting Fellow of the University.

In mid-1999, Tridgell joined the [[Levanta|LinuxCare]] company's office in Canberra as their first Australian employee. He helped to assemble 14 staff for a research and development team known as [[Ozlabs|OzLabs]]. [[Linux]] and open-source companies were quite a new concept at this stage. Tridgell was made a research fellow of Linuxcare in 2000.

In March 2001, Tridgell joined [[VA Software|VA Linux Systems]]. He worked in the [[network attached storage]] division for VA Linux Systems, making enhancements to Samba and the [[Linux kernel]] to provide enhanced performance for their network-attached storage device range.

Tridgell continued his work with network-attached storage technologies when he joined [[Quantum Corporation]] as a Senior Engineer in the Systems Storage Group. His role once again involved developing functionality and efficiency modifications into Samba to enhance Quantum's Guardian network-attached storage device range. One of the features that he added to Samba at this time was support for [[Microsoft]]'s [[Active Directory]] technology, a new authentication system introduced with Microsoft's [[Windows 2000|Windows 2000 Server]] product range.

In 2004, Tridgell was employed by [[IBM]] working remotely for the [[Almaden Research Center]]. In January 2005, he joined the [[OSDL]] on a one-year fellowship<ref>http://www.osdl.org/newsroom/press_releases/2005/2005_01_17_beaverton.html</ref>; he then returned to IBM.<ref>http://www.osdl.org/newsroom/press_releases/2006/2006_Feb_01_beaverton.html</ref>

==Awards==
* In October [[2003]], [[The Bulletin]] magazine judged Tridgell to be Australia's smartest [[Information and Communications Technology]] person.<ref>http://sites.ninemsn.com.au/smart100/default.asp</ref><ref>http://bulletin.ninemsn.com.au/article.aspx?id=135066</ref>
* In January [[2006]], the [[Free Software Foundation]] awarded Tridgell its [[2005]] [[Award for the Advancement of Free Software]], for his work on Samba, the Linux kernel, and rsync. Tridgell was considered to have furthered an important goal of the free software movement since the founding of [[GNU]], analyzing ways for free software to interact with widespread proprietary systems to allow people to more easily move away from those systems.

==References==
{{reflist}}

==External links==
{{portal|Free software|Free Software Portal Logo.svg}}
* [http://www.samba.org/~tridge/ Andrew Tridgell's website]
* [http://samba.org/~tridge/phd_thesis.pdf Efficient Algorithms for Sorting and Synchronization (PhD thesis)] - (406kB PDF)
{{FOSS celeb}}





{{Persondata
|NAME= Tridgell, Andrew
|ALTERNATIVE NAMES=
|SHORT DESCRIPTION=[[Australia]]n [[computer programmer]]
|DATE OF BIRTH=[[February 28]], [[1967]]
|PLACE OF BIRTH=
|DATE OF DEATH=
|PLACE OF DEATH=
}}
{{DEFAULTSORT:Tridgell, Andrew}}
[[Category:Australian computer programmers]]
[[Category:Free software programmers]]
[[Category:IBM employees]]
[[Category:1967 births]]
[[Category:Living people]]
[[Category:People from the Australian Capital Territory]]
[[Category:University of Sydney alumni]]
[[Category:Australian National University alumni]]

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