CAP Theorem and Routing

In 2000, Eric Brewer was observing and discussing the various characteristics of database systems. Through this work, he observed that a database generally has three characteristics— Consistency, which means the database will produce the same result for any two readers who happen to read a value at the same moment in time. Availability, which means…

Securing BGP: A Case Study (5)

BGP provides reachability for the global ‘net, as well as being used in many private networks. As a system, BGP (ultimately) isn’t very secure. But how do we go about securing BGP? This series investigates the questions, constraints, and solutions any proposal to secure BGP must deal with as a case study of asking the…

Reaction: BGP convergence, divergence & the ‘net

Let’s have a little talk about BGP convergence. We tend to make a number of assumptions about the Internet, and sometimes these assumptions don’t always stand up to critical analysis. . . . On the Internet anyone can communicate with anyone else – right? -via APNIC Geoff Huston’s recent article on the reality of Internet…

DoS’ing your mind: Controlling information inflow

Everyone wants your attention. No, seriously, they do. We’ve gone from a world where there were lots of readers and not much content, to a world where there is lots of content, and not many readers. There’s the latest game over here, the latest way to “get 20,000 readers,” over there, the way to “retire…

Securing BGP: A Case Study (4)

In part 1 of this series, I looked at the general problem of securing BGP, and ended by asking three questions. In part 2 and part 3, I considered the third question: what can we actually prove in a packet switched network. For this section, I want to return to the first question: Should we…

Securing BGP: A Case Study (3)

To recap (or rather, as they used to say in old television shows, “last time on ‘net Work…”), this series is looking at BGP security as an exercise (or case study) in understanding how to approach engineering problems. We started this series by asking three questions, the third of which was: What is it we…

Cultivate questions

Imagine that you’re sitting in a room interviewing a potential candidate for a position on your team. It’s not too hard to imagine, right, because it happens all the time. You know the next question I’m going to ask: what questions will you ask this candidate? I know a lot of people who have “set…

Securing BGP: A Case Study (2)

In part 1 of this series, I pointed out that there are three interesting questions we can ask about BGP security. The third question I outlined there was this: What is it we can actually prove in a packet switched network? This is the first question I want dive in too—this is a deep dive,…

Securing BGP: A Case Study (1)

What would it take to secure BGP? Let’s begin where any engineering problem should begin: what problem are we trying to solve? In this network—in any collection of BGP autonomous systems—there are three sorts of problems that can occur at the AS level. For the purposes of this explanation, assume AS65000 is advertising 2001:db8:0:1::/64. While…

Fear itself: Thinking through change and turmoil

Fair warning: this is going to be a controversial post, and it might be considered a bit “off topic.” Maybe it’s just the time of year for fear. Or maybe it’s several conversations I’ve been involved in recently. Or maybe it’s the result of following over 150 blogs on a daily basis covering everything from…