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Deliberate security threats

Dave Farquhar security October 1, 2019October 5, 2019

A friend of a friend suggested to me that I should carefully preserve my Commodores and other vintage computer gear, because it’s the only secure computer equipment available. I said I don’t complain too loudly since security is my job. He then said I’ll always have a job, because so many security threats are deliberate. While he’s not wrong, saying all security threats are deliberate is unhealthy. Here’s why.

Deliberate security threats certainly exist, because planting backdoors in the supply chain is the best way to get into certain highly sensitive networks. But I’ll argue that more security threats are honest mistakes than intentional sabotage.

IBM PC vs XT

Dave Farquhar Retro Computing September 30, 2019August 15, 2026

The difference between an original IBM PC and a PC/XT seems subtle today. The XT wasn’t a huge upgrade over the PC, but the improvements were enough to be significant. The changes IBM made greatly extended the lifespan of the XT, and that’s one reason XTs are so much more common than PCs today. Let’s take a look at the IBM PC vs XT.

The PC/XT had the same CPU running at the same speed and couldn’t take any additional memory over the PC. But the XT was more expandable, and in the late 1980s, that was everything.

Lionel’s American Flyer “buyout”

Dave Farquhar Toy trains September 27, 2019September 7, 2019

Lionel and American Flyer competed with one another in the 1950s. Most Lionel and Flyer enthusiasts know that Lionel now owns American Flyer. Here’s how Lionel’s American Flyer “buyout” happened.

How long should you let spray paint dry?

Dave Farquhar DIY September 26, 2019March 26, 2023

How long should you let spray paint dry? It varies depending on the paint, and you should always read the can to get specific advice for the paint you’re using, since my favorite brand might be different from yours. But generally speaking, an hour is the absolute minimum.

A more realistic minimum safe drying time for spray paint is about 8 hours. Some hobbyists let their paint sit and cure for a full week before they assemble the item and put it into service, and they’ve had excellent results with this practice. Your can is your guide, because dry times can and do vary between brand and type of spray paint. So always, always check the manufacturer’s instructions on your can. But here are some general guidelines.

How do emulators work?

Dave Farquhar Hardware September 25, 2019December 19, 2024

Emulation is the black art of running software designed for one computer or game system on another system that normally wouldn’t be compatible. Emulation has existed since the 1970s, but is much more practical today. Here’s how emulators work.

Strictly speaking, emulators work like a translator, sitting between hardware and software and translating between the two so the software doesn’t realize it’s running on something else. Just like a human translator, there’s overhead involved in this, but modern computers are fast enough that emulation is more practical today than it was in the 1980s, even though plenty of emulators existed even then.

Cyber security degree or certifications?

Dave Farquhar security September 24, 2019January 23, 2022

From time to time I get questions from people looking to break into my field. Here’s a good one: What’s better to get, a cyber security degree or certifications?

If you’re in school now, get the degree. But if you’re not currently in school, and can learn on your own, the certification route is much cheaper, and probably faster. The key is having something on your resume that gets you through HR, and most companies know they can’t demand both.

How to find train shows

Dave Farquhar model railroading, Toy trains September 20, 2019September 2, 2019

The weather will be cooling off soon, and that means it will be time for more train shows. But how do you go about finding train shows? Here are some of my favorite tips.

Using a CD-ROM drive in MS-DOS

Dave Farquhar Retro Computing September 19, 2019May 31, 2024

Loading a CD-ROM device driver in DOS is a bit of a lost art and it wasn’t that easy to find information on how to do it in the 90s either. If you want to use a CD-ROM drive in MS-DOS, here’s how to find, load and configure the driver.

Using a CD-ROM drive in MS-DOS requires loading a CD-ROM driver in config.sys as well as loading MSCDEX.EXE in autoexec.bat. If you match the /D switch on both, the drive will work, but there are tricks to getting optimal performance and memory usage.

Why patching can make your Kenna score go up instead of down

Dave Farquhar security September 18, 2019August 25, 2019

Kenna is a revolutionary vulnerability management tool. It completely changed my approach to vulnerability management. But it can be hard to get used to. The most maddening thing about it is how you can deploy an update, and then your Kenna score increases. That’s not the outcome you wanted. Here’s why patching can make your Kenna score go up instead of down, and what to do about it.

Kenna’s math is tricky, but the thing to remember is the risk score isn’t exactly an average. Once you deploy enough patches for high-risk vulnerabilities, your risk score will start to drop as expected. The key is sticking with it long enough for the score to drop.

BIOS hard drive limits

Dave Farquhar Retro Computing September 17, 2019December 24, 2025

Back in the old days, we had to worry about BIOS hard drive limits. I couldn’t put a 40 GB hard drive in my 486 because it couldn’t recognize a drive of that size. That wasn’t a big problem in the 90s since I couldn’t get one of those in the 90s, but now that we’re starting to dust off those old systems and put modern storage solutions in them, sometimes we have to think about those limits again.

Generally speaking, older systems tend to be limited to hard drive sizes of 528 MB, 2.1 GB, 4.2 GB, 8.4 GB, 33.8 GB, or 137 GB. Sometimes you can configure the system to ignore the extra size, or you can use another workaround.