Metaswitch Networks Interview Questions & Answers

My day began with three short 15 minute aptitude tests. The first one was series forming (40 questions). The second was pattern recognition (30 questions). The last one was simple numerical problems (25 questions).
This was followed by three longer tests (30 min, 30 min, 25 min), each with a question that required detailed analysis. The first was to develop an algorithm for a communication example. The second involved the dry run of a simple code. The last was a logic development for a card game. No programming knowledge was necessary; they were simply testing the strength of logic.
At the end, there was an interview to discuss my answers to each of the long questions (mainly 1 and 3) and to identify loopholes in my logic. It went on to include questions about my academic and professional background and future career plans.

The dry run of the program was difficult, simply because it involved about 13 variables, a lot of if-then-else loops, procedure calls and there wasn't enough time.

Practice pattern recognition and dry run of codes.
Make sure your logic holds up against potential threats.

The interviewer seemed very open to various approaches to a problem and during the discussion kept egging me towards possible solutions. The atmosphere was positive and friendly.
The experience was more of a chat and less of an interview.