Andrew S. Tanenbaum

Tanenbaum's textbooks on computer science include:

• Structured Computer Organization[14] (1976)
• Computer Networks, co-authored with David J. Wetherall and Nickolas Feamster[15] (1981)
• Operating Systems: Design and Implementation, co-authored with Albert Woodhull[16] (1987)
• Modern Operating Systems[3] (1992)
• Distributed Operating Systems[4] (1994)
• Distributed Systems: Principles and Paradigms, co-authored with Maarten van Steen[2] (2001)

His book, Operating Systems: Design and Implementation and MINIX were Linus Torvalds' inspiration for the Linux kernel. In his autobiography Just for Fun, Torvalds describes it as "the book that launched me to new heights".

His books have been translated into many languages including Arabic, Basque, Bulgarian, Chinese, Dutch, French, German, Greek, Hebrew, Hungarian, Italian, Japanese, Korean, Macedonian, Mexican Spanish, Persian, Polish, Portuguese, Romanian, Russian, Serbian, and Spanish.[10] They have appeared in over 175 editions and are used at universities around the world.[17]

Tanenbaum has had a number of PhD students who themselves have gone on to become widely known computer science researchers. These include:

• Henri Bal, professor at the Vrije Universiteit in Amsterdam
• Frans Kaashoek, professor at MIT
• Werner Vogels, Chief Technology Officer at Amazon.com[5]

In the early 1990s, the Dutch government began setting up a number of thematically oriented research schools that spanned multiple universities. These schools were intended to bring professors and PhD students from different Dutch (and later, foreign) universities together to help them cooperate and enhance their research.

Tanenbaum was one of the cofounders and first Dean of the Advanced School for Computing and Imaging (ASCI). This school initially consisted of nearly 200 faculty members and PhD students from the Vrije Universiteit, University of Amsterdam, Delft University of Technology, and Leiden University. They were especially working on problems in advanced computer systems such as parallel computing and image analysis and processing.

Tanenbaum remained dean for 12 years, until 2005, when he was awarded an Academy Professorship by the Royal Netherlands Academy of Arts and Sciences, at which time he became a full-time research professor. ASCI has since grown to include researchers from nearly a dozen universities in The Netherlands, Belgium, and France. ASCI offers PhD level courses, has an annual conference, and runs various workshops every year.

The Amsterdam Compiler Kit is a toolkit for producing portable compilers. It was started sometime before 1981 and Andrew Tanenbaum was the architect from the start until version 5.5.[18]

In 1987, Tanenbaum wrote a clone of UNIX, called MINIX (MINi-unIX), for the IBM PC. It was targeted at students and others who wanted to learn how an operating system worked. Consequently, he wrote a book that listed the source code in an appendix and described it in detail in the text.[19] The source code itself was available on a set of floppy disks. Within three months, a Usenet newsgroup, comp.os.minix, had sprung up with over 40,000 subscribers discussing and improving the system. One of these subscribers was a Finnish student named Linus Torvalds, who began adding new features to MINIX and tailoring it to his own needs. On October 5, 1991, Torvalds announced his own (POSIX-like) kernel, called Linux, which originally used the MINIX file system but is not based on MINIX code.[20]

Although MINIX and Linux have diverged, MINIX continues to be developed, now as a production system as well as an educational one.[21] The focus is on building a highly modular, reliable, and secure operating system. The system is based on a microkernel, with only 5000 lines of code running in kernel mode.[22] The rest of the operating system runs as a number of independent processes in user mode, including processes for the file system, process manager, and each device driver. The system continuously monitors each of these processes, and when a failure is detected is often capable of automatically replacing the failed process without a reboot, without disturbing running programs, and without the user even noticing. MINIX 3, as the current version is called, is available under the BSD license for free.

In 2017, Google discovered that the Intel Management Engine runs MINIX in ring -3.[23] After Tanenbaum read about this, he published an open letter to Intel, detailing conversations with Intel software engineers that occurred several years ago, where they wanted his assistance in modifying MINIX to work on "some secret project". He believes that Intel chose MINIX for this purpose because it is licensed under the BSD-3-Clause license, which allowed Intel to modify the MINIX source code without freely distributing their modified version. In his letter, Tanenbaum claims that MINIX is the most widespread operating system,[24] and this is interpreted by the community as Tanenbaum believing that he has won the Tanenbaum–Torvalds debate.[25] It is hard to know if MINIX or Linux is more popular, as Intel does not publish chipset sales figures, and there is no direct way to find the number of systems running Linux or MINIX. However, Linux has seen much more widespread use in the server space, is widely used in embedded systems, and also runs on all Android phones, which account for at least 3 billion active devices,[26] meaning that it is likely that Linux is the most widespread operating system, although there is no concrete data to back up this claim.

Tanenbaum has also been involved in numerous other research projects in the areas of operating systems, distributed systems, and ubiquitous computing, often as supervisor of PhD students or a postdoctoral researcher. These projects include:

• Amoeba[27]
• Globe[28]
• Mansion[29]
• Orca[30]
• Paramecium[31]
• RFID Guardian[32]
• Turtle F2F

In 2004, Tanenbaum created Electoral-vote.com, a web site analyzing opinion polls for the 2004 U.S. Presidential Election, using them to project the outcome in the Electoral College. He stated that he created the site as an American who "knows first hand what the world thinks of America and it is not a pretty picture at the moment. I want people to think of America as the land of freedom and democracy, not the land of arrogance and blind revenge. I want to be proud of America again."[33] The site provided a color-coded map, updated each day with projections for each state's electoral votes. Through most of the campaign period Tanenbaum kept his identity secret, referring to himself as "the Votemaster" and acknowledging only that he personally preferred John Kerry. Mentioning that he supported the Democrats, he revealed his identity on November 1, 2004, the day before the election, and also stating his reasons and qualifications for running the website.[33]

Through the site he also covered the 2006 midterm elections, correctly predicting the winner of all 33 Senate races that year.

For the 2008 elections, he got every state right except for Indiana, which he said McCain would win by 2% (Obama won by 1%) and Missouri, which he said was too close to call (McCain won by 0.1%). He correctly predicted all the winners in the Senate except for Minnesota, where he predicted a 1% win by Norm Coleman over Al Franken. After 7 months of legal battling and recounts, Franken won by 312 votes (0.01%).

In 2010, he correctly projected 35 out of 37 Senate races in the Midterm elections on the website. The exceptions were Colorado and Nevada.

Electoral-vote.com incorrectly predicted Hillary Clinton would win the 2016 United States presidential election. The website incorrectly predicted Clinton would win Wisconsin, Michigan, Pennsylvania, North Carolina, and Florida. Electoral-vote.com did not predict a winner for Nevada, which Clinton would win. The website predicted the winners of the remaining 44 states and the District of Columbia correctly.[34]

Tanenbaum in Târgu Mureș

Tanenbaum is 4th from left

• On May 12, 2008, Tanenbaum received an honorary doctorate from Universitatea Politehnica din București. The award was given in the academic senate chamber, after which Tanenbaum gave a lecture on his vision of the future of the computer field. The degree was given in recognition of Tanenbaum's career work, which includes about 150 published papers, 18 books (which have been translated into over 20 languages), and the creation of a large body of open-source software, including the Amsterdam Compiler Kit, Amoeba, Globe, and MINIX.
• On October 7, 2011, Universitatea Petru Maior din Târgu Mureș (Petru Maior University of Târgu Mureș) granted Tanenbaum the Doctor Honoris Causa (honorary doctorate) title for his remarkable work in the field of computer science and achievements in education. The academic community is hereby honoring his devotion to teaching and research with this award. At the ceremony, the Chancellor, the Rector, the Dean of the Faculty of Sciences and Letters, and others all spoke about Tanenbaum and his work. The pro-rector then read the 'laudatio,' summarizing Tanenbaum's achievements. These include his work developing MINIX (the predecessor to Linux), the RFID Guardian, his work on Globe, Amoeba, and other systems, and his many books on computer science, which have been translated in many languages, including Romanian, and which are used at Petru Maior University.