EuroSys 2011, day one
Session 1: Data, Data, Data
Keypad: An Auditing File System for Theft-Prone Devices
The challenge is that mobile devices are prone to theft and loss, and encryption is not sufficient, because people have a habit of attaching the password to the device on a post-it, and it is vulnerable to social and hardware attack. Aim is to know what (if any) data is compromised in the event of a loss, and prevent future compromises. Solution is to force remote auditing on every file access (with encryption), by storing keys on the auditing server; this is done in the file system. File system metadata are stored on the trusted server. There are significant challenges in making this performant: caching/prefetching/preallocation are used to optimize key requests, but file creation is more challenging to optimize due to file systems semantics. Blocking filename registrations have correct semantics, but poor performance; vice versa for non-blocking registrations. To reconcile this, force a thief to use blocking semantics while allowing the user to use non-blocking semantics (as much as possible), which is based on using filenames as public keys. Second challenge is allowing disconnected access: the idea is to use multiple devices carried by the user to cross-audit file accesses, which still requires devices to hoard keys before going disconnected. - dgm36
Systems for Future Multi-Core Architectures
Today was workshop day at EuroSys 2011, and I spent the day at the inaugural SFMA workshop. The aim of the workshop was to bring together practitioners from the fields of operating system, programming language and computer architecture research, and provoke discussion about new trends in parallel computing. The most notable thing about the workshop was the number of practitioners that it attracted, starting off with standing room only at 9am in the morning, and maintaining a respectable audience of 35 people through to 5pm. I was on the program committee for the workshop, and Ross did a great job of organising the whole thing.
The Philosophy of Trust and Cloud Computing
The Philosophy of Trust and Cloud Computing
April 5/6, Corpus Christi, Cambridge
Sponsored by Microsoft Research
Richard Harper (MSR) and Alex Oliver (Cambridge) outlined
the goals of the meeting, and everyone introduced themselves - the
majority of attendees were either in Social Science/Anthropology or
Philosophy, with a few industrials and a couple of technical people
from Computing (networks&security).
The talks were mostly in the social science style
(people literally "read" papers, rather than powerpoint), so one had
to concentrate a bit more than usual, rather than looking at
bulletpoints and catching up on email/facebook.
Supporting control flow in the CIEL execution engine
How do you write a program that runs on hundreds or thousands of computers? Over the last decade, this has become a real concern for many companies that must be able to handle ever-growing data sets in order to stay in business. When those data sets grow to terabytes or petabytes in size, a single disk (or even a RAID array) can't deliver the data fast enough, so a solution is needed to exploit the throughput of hundreds or thousands of disks in parallel. In this post, I'll introduce various solutions to this problem, and explain how our CIEL execution engine supports a larger class of algorithms than existing systems.
20th International World Wide Web Conference – WWW 2011
I am just back from Hyderabad, in India, where I attended the 20th International World Wide Web Conference, also known as WWW 2011, to present our work on tracking geographic social cascades to improve video delivery.  This conference, organised as usual by the International World Wide Web Conference Committee (IW3C2),  represents the annual opportunity for the international community to discuss and debate the evolution of the Web, providing a mixture of academic and industrial content.
The word cloud shows pretty well the main themes of the conference this year, which heavily revolved around two large pivotal aspects: "social" and "search". Interestingly, there was not any attempt of merging the two things together, as Aardvark tried last year. Not surprisingly, "networks" are still popular in the community, and "Twitter" still enjoys a lot of interest, even though this may change with their new controversial Terms Of Service, which are likely to hamper social media data harvesting.
Overall it is a fairly big conference, with 2 initial days of workshops, tutorial and panels and then 3 days with 81 research papers. Also, there were three world-known personalities such as Dr. Abdul Kalam, Sir Tim Berners-Lee and Christos Papadimitriou that gave a keynote each. I will give a brief summary of the main research themes, with pointers to the most interesting papers. However, it was physically impossible to attend all the research sessions, as they were often happening simultaneously: you can find much more information on the conference website and on the official proceedings.