Monday, June 30, 2008

HPDC'2008 - Part I

Last week I participated to two great conferences: the International Symposium in High Performance Distributed Computing (HPDC) and the USENIX. Both events took place in Boston, MA, USA.

There a lot of interesting things to mention. Thus, to avoid a single long post, I will describe a few presentations that I attended (and discuss some ideas) in a series of short posts.

In the first two days at HPDC, there were two interesting workshops: UPGRADE-CN (P2P and Grids for the Development of Content Networks) and MMS (Managed Multicore Systems).

The two workshops had works related to the research projects I am currently working on.

Molina [1] presented his work on designing two protocols that enable collaborative content delivery in mobile transient networks. By transient networks, the authors mean networks composed of devices that are geographically co-located for a short period such as a music festival.

The authors suggest to exploit the multiple network interfaces currently available in most mobile devices and to enable collaborative use of these multihomed devices.

The idea is quite interesting. In particular, it raises some issues from the perspective of distributed resource sharing. It would be good to understand whether incentive mechanisms are necessary in transient networks. The idea is to encourage users to share their connections with a community for collaborative downloading/streaming of content.

On top of that, a nice follow-up work would be to investigate the feasibility of collaborative data dissemination protocols, which are widely used in the Internet (e.g. BitTorrent), in the transient networks scenarios.

[1] Molina et al. "A Social Framework for Content Distribution in Mobile Transient Networks". In UPGRADE-CN'2008.

Thursday, June 05, 2008

IPTV Viewing Habits and Netflix Player

The IPTPS 2008 has an interesting paper on exploiting TV Viewing Habits to reduce the traffic on the ISP backbone generated by IPTV consumers.

"On Next-Generation Telco-Managed P2P TV Architectures" by Meeyoung Cha (KAIST), Pablo Rodriguez (Telefonica Research, Barcelona), Sue Moon (KAIST), and Jon Crowcroft (University of Cambridge).

In this paper the authors analyze the utilization o P2P content distribution techniques to reduce network overhead in a Internet Service Provider IPTV infrastructure. To exploit the patterns of channel holding time, channel popularity and the correlation between the time of the day and the number of viewers, the authors propose a locality-aware P2P content distribution scheme that reduces the traffic on the ISP backbone.

From the paper:

we ascertain the sweet spots and the overheads of server-based unicast, multicast, and serverless P2P and also show the empirical lower bound network cost of P2P (where cost reduction is up to 83% compared to current IP multicast distribution


We believe that our work provides valuable insights to service providers in designing the next-generation IPTV architecture. Especially, it highlights that dedicated multicast is useful for few of the extremely popular channels and that P2P can handle a much larger number of channels while imposing very little demand for infrastructure.

This week I saw some news on the internal characteristics of the Netflix Player. Immediately, I thought of the paper from IPTPS as a possible optimization to the Netflix Player.

The NetFlix player is supposed to use the conventional broadband connection, as opposed to well provisioned IPTV architectures described in Cha et al. Perhaps, the locality-aware P2P content distribution technique is even more interesting in the Netflix Player case.

Nevertheless, the viewing habits and interest sharing among Netflix users may differ dramatically from what is observed in the IPTV environment, which would impact the efficiency of the locality-aware P2P content distribution.

Tuesday, June 03, 2008

Oh My Goosh!

If you like typing your commands away to interact with your computer, you will like this: Goosh :-)

From Slashdot: goosh, the Unofficial Google Shell posted by kdawson on Monday June 02, @07:26PM.

It's essentially a browser-oriented, shell-like interface that allows you to quickly search Google (and images and news) and Wikipedia and get information in a text-only format.