Andrew Tridgell

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Andrew Tridgell

OAM
Andrew Tridgell.jpg
Tridgell in 2006
Born (1967-02-28) 28 February 1967 (age 57)
Sydney, Australia
NationalityAustralian
Other namesTridge
OccupationProgrammer
Known for rsync, Samba, rzip, ccache, ArduPilot

Andrew "Tridge" Tridgell OAM (born 28 February 1967) is an Australian computer programmer. He is the author of and a contributor to the Samba file server, and co-inventor of the rsync algorithm.

Contents

He has analysed complex proprietary protocols and algorithms, to allow compatible free and open source software implementations.

Projects

Tridgell was a major developer of the Samba software, analyzing 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 dissertation, he co-developed rsync, including the rsync algorithm, a highly efficient file transfer and synchronisation tool. He was also the original author of rzip, which uses a similar algorithm to rsync. He developed spamsum,[ clarification needed ] based on locality-sensitive hashing algorithms. [1]

He is the author of KnightCap, a reinforcement-learning based chess engine.

Tridgell was also a leader in hacking the TiVo to make it work in Australia, which uses the PAL video format. [2]

In April 2005, Tridgell tried to produce free software (now known as SourcePuller) that interoperated with the BitKeeper source code repository. This was cited as the reason that BitMover revoked a license allowing Linux developers free use of their BitKeeper product. [3] Linus Torvalds, the creator of the Linux kernel, and Tridgell were thus involved in a public debate about the events, in which Tridgell stated that, not having bought or owned BitKeeper – and thus having never agreed to its license – he could not violate it, and was analyzing the protocol ethically, as he had done with Samba. Tridgell's involvement in the project resulted in Torvalds accusing him of playing dirty tricks with BitKeeper. [4] Tridgell claimed his analysis started with simply telneting to a BitKeeper server and typing help. [5]

In 2011 Tridgell became involved with the software development of ArduPilot Mega, [6] an open source Arduino-based UAV controller board, working on an entry with CanberraUAV [7] for the UAV Challenge Outback Rescue. [8]

Academic achievements

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 dissertation 'Efficient Algorithms for Sorting and Synchronization' was based on his work on the rsync algorithm. [9]

Awards and honours

Related Research Articles

In cryptography, SHA-1 is a hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest – typically rendered as 40 hexadecimal digits. It was designed by the United States National Security Agency, and is a U.S. Federal Information Processing Standard. The algorithm has been cryptographically broken but is still widely used.

Samba is a free software re-implementation of the SMB networking protocol, and was originally developed by Andrew Tridgell. Samba provides file and print services for various Microsoft Windows clients and can integrate with a Microsoft Windows Server domain, either as a Domain Controller (DC) or as a domain member. As of version 4, it supports Active Directory and Microsoft Windows NT domains.

rsync File synchronization protocol and software

rsync is a utility for transferring and synchronizing files between a computer and a storage drive and across networked computers by comparing the modification times and sizes of files. It is commonly found on Unix-like operating systems and is under the GPL-3.0-or-later license.

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Delta encoding is a way of storing or transmitting data in the form of differences (deltas) between sequential data rather than complete files; more generally this is known as data differencing. Delta encoding is sometimes called delta compression, particularly where archival histories of changes are required.

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Git is a distributed version control system that tracks changes in any set of computer files, usually used for coordinating work among programmers who are collaboratively developing source code during software development.

<span class="mw-page-title-main">Sparse file</span>

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<span class="mw-page-title-main">Mercurial</span> Distributed revision-control tool for software developers

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<span class="mw-page-title-main">BackupPC</span>

BackupPC is a free disk-to-disk backup software suite with a web-based frontend. The cross-platform server will run on any Linux, Solaris, or UNIX-based server. No client is necessary, as the server is itself a client for several protocols that are handled by other services native to the client OS. In 2007, BackupPC was mentioned as one of the three most well known open-source backup software, even though it is one of the tools that are "so amazing, but unfortunately, if no one ever talks about them, many folks never hear of them".

Remote Differential Compression (RDC) is a client–server synchronization algorithm that allows the contents of two files to be synchronized by communicating only the differences between them. It was introduced with Microsoft Windows Server 2003 R2, is included with later Windows client and server operating systems, but by 2019 is not being developed and is not used by any Microsoft product.

<span class="mw-page-title-main">Fingerprint (computing)</span> Digital identifier derived from the data by an algorithm

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ArduPilot is an open source, uncrewed vehicle Autopilot Software Suite, capable of controlling:

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SourcePuller is an open-source client for accessing the BitKeeper version control system. It was originally developed by Andrew Tridgell, who – according to BitKeeper developer Larry McVoy – reverse engineered the BitKeeper protocol. While not widely used itself, it is best known for triggering the BitKeeper controversy, which sparked the switch of the Linux kernel from BitKeeper to Git.

References

  1. Jesse Kornblum (2006). "Identifying almost identical files using context triggered piecewise hashing" (PDF). DFRWS. Archived (PDF) from the original on 9 October 2022. Retrieved 23 February 2014.
  2. Tridgell, Andrew. "TiVo Ethernet". Archived from the original on 14 January 2012. Retrieved 17 August 2012.
  3. git [LWN.net]
  4. Orlowski, Andrew (14 April 2005). "Torvalds knifes Tridgell: Kernel source row turns nasty". The Register .
  5. "Groklaw – Tridge Speaks". Archived from the original on 27 May 2011. Retrieved 5 September 2007.
  6. Andrew Tridgell's Page Archived 14 April 2012 at the Wayback Machine . DIY Drones. Retrieved on 19 September 2013.
  7. "CanberraUAV – Open Source Civilian UAV Development". web.archive.org. 3 December 2018. Retrieved 31 March 2024.
  8. UAV Challenge – Outback Rescue 2013 – Home Archived 10 February 2012 at the Wayback Machine . Retrieved on 19 September 2013.
  9. "Andrew Tridgell - The Mathematics Genealogy Project". www.genealogy.math.ndsu.nodak.edu. Retrieved 11 December 2017.
  10. The Bulletin Smart 100 Archived 18 March 2007 at the Wayback Machine
  11. The Bulletin publishes for the last time Archived 9 May 2007 at the Wayback Machine
  12. Google Open Source Blog: ... and the winners of the 2008 Google-O'Reilly Open Source Awards are
  13. FOSS folk who make us proud, Sam Varghese, iTWire, 2007-12-25, accessed 27 September 2009
  14. "ANU Graduation Ceremony 1 - from ANU Graduation Ceremony 2". Livestream. Retrieved 11 December 2018.
  15. "ANU Honorary degree: Dr Andrew Tridgell". 13 December 2018.
  16. "Australia Day 2020 Honours List".