Month: February 2015

Middleboxes considered harmful: DNS Edition

This article is brief overview of how middleboxes interact with DNS traffic. In particular I’m interested in finding out the answers to the following: Will middleboxes drop/modify DNS traffic and what is the purpose of this: stopping abuse, security, buggy implementations, advertising or censorship? Therefore does using your own stub resolver and recursive nameserver free you Read More

DNS question: Avoiding circular dependencies without glue records?

Can someone help me the understand the following: When the authoritative name server for a domain (e.g. lies within the domain over which it has authority (e.g., a query (e.g. for to the parent domain (e.g. .com) will include both the NS RRs, to delegate authority of the domain to the nameservers, Read More

Comcast blocking

Today, people love to hate their ISPs, they have a public image problem. A great example of this when Comcast apparently blocking NASA’s website in 2012. In fact, Comcast was the only major US ISP to be using DNSSEC validating resolvers thus where the only ones affected when NASA’s website failed to properly sign their DNS responses. Read More

Video: An overview of secure name resolution [29c3]

Here is an excellent talk by Matthäus Wander, introducing DNSSEC, DNSCurve and few other DNS extensions.   A few points of interest: stub resolvers need new API’s to report DNSSEC validation failures, then browsers can provides users with “TLS like” failure messages AD flag is useless as there is no validation, yet windows 7/8 still read Read More

Talk & Poster @ 2nd Annual Oxbridge Women in Computer Science Conference

I’ve been accepted for a talk and a poster at the 2nd Annual Oxbridge Women in Computer Science Conference on 16th March 2015. My submitted abstract is here. Read More

We’re coming to letter box near you

The January edition of the Operating System Review is now out, look out for “Raft Refloated: Do We Have Consensus?”. Also available without dead trees. Read More

Part 1: Running your own DNS Resolver with MirageOS

The following is the first part in a step-by-step guide to setting up your own DNS resolver using MirageOS. I will be running this on a low power, low cost ARM device called the Cubieboard 2. Up to date code for each version of the DNS resolver is on Github. This guide assumes some basic experience of Read More

Squashing git commits

to squash the last n commits (e.g 37) into one git reset –soft HEAD~37 && git commit –edit -m”$(git log –format=%B –reverse HEAD..HEAD@{1})” git push -f source:, thanks david Read More

Lab Culture – How to ask the right questions?

Thanks to Justine, at the excellently named Lavender Martini Border Gateway Protocol for sharing a link to this blog post on Prospective Students and Lab Culture. Useful food for thought, not just for Part 2 students. Read More

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