I've started writing a new series for TechTarget SearchNetworkingChannel.com called Traffic Talk. The first edition is called DNS troubleshooting and analysis. I wrote it in early June, way before Dan Kaminsky's DNS revelations, so it has nothing to do with that affair. From the start of the article:
Welcome to the first edition of Traffic Talk, a regular SearchNetworkingChannel.com series for junior to intermediate networkers who troubleshoot business networks. In these articles we examine a variety of open source tools that expose and analyze different types of network traffic. In this edition we explore the Domain Name System (DNS), the mechanism that translates IP addresses to hostnames and back, plus a slew of other functions.