Why do those secure certificate errors sometimes pop up when you visit certain websites? What should you do when you see it? [More]

It is commonly understood that you can only have a single HTTPS (SSL/TLS) web site per IP address. This article describes why and how you can have many SSL/TLS web sites on a single IP address, and why you might not want to do it anyway. [More]

Describing some of the basics for developers who want to use encryption in their programs. [More]

A quick note on an Internet infrastructure security issue made public today. [More]