Most bugs which kill people (and projects) are spec / requirements bugs, not implementation bugs. This could be a missing top-level requirement, a missing implication of some requirement on a lower-level spec, or some emergent behavior which was never spec’d. This post will explore the problem of spec bugs, and discuss possible solutions. Note that … More It’s the spec bugs that kill you
A companion post talks about spec bugs and ways to avoid them. Spec / requirement bugs (as opposed to implementation bugs) occur when the spec for a subsystem does not take into account some higher-level, full-system requirements. Spec bugs are pretty important, so here I’ll talk about some common verification-related concepts, and (my interpretation of) … More Terminology related to spec bugs
I started writing this blog mainly for feedback (see here), but did not know what to expect. Turns out I get good comments in the blog itself, but also (and unexpectedly) quite a few comments in private emails. Private emails are good, but not ideal (because you, gentle reader, don’t get to see them, and … More Some good comments I got lately about requirements
The topic of Formal Verification (FV) and how it relates to Coverage Driven Verification (CDV) came up in some previous posts and in a comment thread. So allow me to briefly discuss it – I promise to get back to the main course soon. Some definitions Before I continue, let me define what I mean by … More FV has much better PR than CDV
I got interesting comments from some [1] loyal readers of this blog, about these “examples of systems to verify” mentioned in my initial post: Some people claimed that these systems are really so different in scale that they are really incomparable. In particular, I heard the claim that hardware verification (where I spent much of … More On that “verification range” issue
I had a breakfast discussion about this simulation-for-transportation-policies with two friends of mine who have been looking into similar topics for years: Nadav Levy and Itzhak Benenson of Tel Aviv Univ. This was triggered by my post about a related topic. Here are the main things I learned during breakfast: They are interested in policies like: … More A breakfast discussion about simulations for transportation policy decision making
I have sent quite a few people the summary of what I saw at the Autonomous Vehicles Test & Development Symposium in Stuttgart. I was pleasantly surprised with the results – a lot of people sent thoughtful answers, or talked to me about it. Here is a summary of what they said, anonymized (because this … More Some feedback on my Stuttgart report
This somewhat-unexpected topic came up in several offline conversations during the Stuttgart symposium On day 1, I had a discussion with a guy who gave the lecture “Impact of driverless mobility on vehicle development and testing” (Thomas delos Santos, CEO, Innovative Mobility Automobile GmbH, Germany). His is a small consultancy house which consults e.g. cities … More Also from Stuttgart: Using simulation for public policy decision making
I travelled to Stuttgart to attend this first-of-a-kind conference. It was interesting for me, because (in Foretellix) I am trying to investigate how dynamic, constrained-random, coverage-driven verification (call it “CDV” – the bread-and-butter of hardware verification) can be extended for verifying complex socio-technical systems. This long(ish) post summarizes my impressions. I did not know much … More My impressions from the Stuttgart Autonomous Vehicles Test & Development symposium
Welcome to the Foretellix blog. Here is a short introduction: My name is Yoav Hollander. I have been doing verification practically forever [1] (e.g. I created the e verification language). By “verification” I mean here roughly “the process of finding bugs (or unintended consequences) in engineered systems before they annoy a customer / destroy a project … More Why this blog