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History of Technology

History of technical devices and systems, with particular interest in computing

Von Neumann Explains Computers, 1946

Jon von Neumann

John von Neumann published the earliest and most influential discussions of how to build electronic digital computers. His earliest known publication on computer design was actually a draft report he created in June, 1945, that was widely distributed among the infant community of computer developers. 

On May 15, 1946, von Neumann gave a detailed talk about the general principles of computer design. He was addressing the US Navy's Mathematical Computing Advisory Panel, a group that oversaw the Navy's computing R&D progams. Like the earlier draft, this talk was quickly transcribed, mimeographed, and distributed. The resulting paper was titled "The Principles of Large-Scale Computing Machines."

My father was about to be discharged from the Navy as this was taking place. He had spent World War II working on classified electronics in Boston. The Navy offered him a civilian job overseeing computer research projects. Thus, a copy of von Neumann's "Principles" paper ended up in his archives. 

I have made a PDF copy of this paper and posted it here. This is a sort of companion to Whirlwind block diagrams I posted earlier. 


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The electronic library debate continues

Cousin Jon emailed me David Pogues' recent blog on copyright, with an observation on digital libraries.

The science and technology world has an interesting analog to the paper vs electronic print music debate. In our world, the problem crops up with professional papers. My own attitude is clear: if I have the choice between downloading a free copy of someone's paper I find on-line, or purchasing a copy from the professional society, I grab the free copy.

Partly this is because the original author doesn't get a penny from publication sales. In many cases the author is lucky if the association prints the paper for free, without requiring "page charges." Another reason is that, in most cases, the paper is actually made available on-line by one or more of its authors.

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CPU-based Security Improvements Adopted Slowly

'Way, 'way back in the 1960s, computer designers tried out different techniques to limit how a computer executed its programs. Some should be pretty well known, like storage protection and the distinction between "kernel mode" for the operating system and "user mode" for applications. Another was data execution prevention (aka "DEP"), where the computer distinguishes between RAM that stores instructions and RAM that stores data. If the program tries to jump into instructions stored in data RAM, the CPU aborts the program.


Fast forward to 2010. Most microprocessors were supporting DEP in the mid 1990s; a few supported it before that. OS support came more slowly. Windows as been using one form or another of this since 2004 in XP Service Pack 2. However, it doesn't matter for most major applications, because they didn't fix their code to take advantage of it. So, if they suffer a buffer overflow, there's nothing to prevent the computer from trundling off to la-la land.

A Memoir of Secure Computing Corporation

Now that Secure Computing Corporation is a memory, having been acquired by McAfee, I'm going to write up a few memories of my own experiences. At one point I posted much of this in the appropriate Wikipedia entry, but that's actually not kosher. Since much of it is based on personal recollection, these words fall in line with what they call "original research." So I'm posting it here.


I joined Secure Computing about a year after it came into existence. It was called "Secure Computing Technology Corporation" at the time. By the time I left, they'd gone through three more company presidents, 4 corporate logos, several mergers, and bounced the corporate headquarters from Minnesota to Silicon Valley.

Intro to Multiprogramming

Back in 1964, Boston's public TV station, WGBH, did a show on interactive computing at MIT. They interviewed Fernando Corbató, MIT's timesharing pioneer, who demonstrated the old CTSS system.

Blaze visits the Titan Missile Museum

Matt Blaze has posted a blog entry following a visit to the Titan Missile Museum that's just south of Tucson, Arizona. It's a well written summary of the place.

Blaze talks a bit about Titan, PALs, and the "butterfly switch;" mechanisms intended to prevent an unauthorized launch. The Titan system didn't have PALs. The butterfly switch, also known as the "Coded Switch System" (CSS), authorizes the launch. PALs were first required on overseas nukes starting in 1962. Titans were never overseas, and the system was already under construction in the continental US by the time the PAL idea arose.

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A 21st Century Family Library

Over the years, our family has bought three copies of the Crosby, Stills & Nash album. My wife and I each bought a vinyl copy back in the '70s. Recently we bought a "clean" (not copy protected) copy from the iTunes music store. I expect that's the last time anyone in our family will have to buy a copy of that album, including all our descendants.

I believe that music sharing is "fair use" within a family. I'm inclined to feel that way about video, and no doubt I'll feel the same way about digitized books. Cousin Jon sent me a couple of links describing "do it yourself" book scanners. I need to get myself one of those. But a family library of digitized books has an interesting implication for publishers: it will decimate the reprint market. My (not-yet-existing) great grandson won't ever have to purchase a copy of Pride and Prejudice and should never have to buy any other books I collect in digital form.

Computers and Health Care

David Himmelstein of Cambridge Hospital and Harvard Med School (with co-authors) recently published a paper on the effect of computerization of hospitals.

The results, as Computerworld put it: Computers don't save hospitals money.

Excellian Logo

This makes sense, especially when you look at the study. They focused on data collected reported by individual hospitals nationwide between 2003 and 2007. Computerization, especially at the clinical level, is incredibly disruptive. Thus, the efficiencies aren't likely to arise soon.

Pragmatic Security: the history of the Visa card

I've been looking at the evolution of electronic funds transfer (EFT) and payment systems recently. My research uncovered a gem: about two years ago, David Stearns completed a dissertation that looks at the early evolution of the Visa card (originally "Bank Americard") in the context of other evolving electronic payment systems. Stearns' work is both readable and filled with interesting information.

Old BankAmericard logo

What I find most fascinating is that the card systems followed the same security trajectory as cell phones. The first cards, like the early analog cell phones, were  vulnerable to fraud. In fact, the cards were absurdly vulnerable to fraud.

However, the promoters believed that the long term benefits of electronic cash were worth the risks. They also assumed without evidence that they could fix the fraud problems eventually.

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Some Tech Lives Forever

The Whirlwind is my favorite first-generation computer. It is also the basis of SAGE, a nationwide air defense system built by IBM in the '50s. Nuclear missiles made SAGE obsolete pretty quickly. By the mid '60s, big chunks of the SAGE computers, affectionately called the AN/FSQ-7, started showing up in surplus.

These parts soon made cameo and even starring appearances in TV shows and movies. Mike Loewen has constructed a web site that tracks "sightings" of Q-7 parts in movies.

Q7 console - Computer History Museum

We've all seen them: those rows of blinkenlights installed at a slight angle and often rigged with pyrotechnics. They appeared in almost every science fiction TV show from the '60s, and many movies. Surprisingly, these ancient panels still show up occasionally. Most recently, panels appeared in the background of a Comcast ad.

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