Distributed Operating Systems

Past Exams

SS 2015

what are the three main problems with replicated systems
how does DNS approaches scalability
few questions about DNS work (partitioning, zones ...)
what does Amdahl's law says (the logic)
if you have a program that is 10% sequential what is the maximum speedup assuming we have infinite cores
write down the formula of Amdahl's law
general questions about trusted computing
scenario question that addresses issues of sealed memory, future versions .... and attacks on Trusted computing
questions about the modeling lecture
what is the difference between two army model and byzantine model
important note I got 1.3 instead of 1.0 because some answers were slow although they were correct so try to answer accurately but fast

To calculate the speedup factor using Amdahl's law variant.
POSIX, gossip protocol and information dissemination.
Locks, spin lock (TS, TTS) but you probably should know ticket lock and MCS lock as well.
In Trusted computing about Sealed memory.
In security (Chapter 08) about Chinese Wall and Capabilities.
While studying, try to imagine some scenarios that you could apply what you just read.

All questions are basically scenarios that you have to understand the problem and how to solve it.

This is my two cents, hope it helps you! Good luck!

main problem in scalable system
trusted computing for multiple Content Vendor Vs Multiple Devices: how it works?
Byzantine problem and two army problem? what are different and which kind of fault can be tolerated with them?
dns about: zone, replication, caching?