Socially-Aware Distributed Systems or Why this Class Collaboration? Anda Iamnitchi

Distributed Systems Collections of stand-alone communicating devices that have a common task or objective Internet-connected computers Mobile devices (cell phones, PDAs) Common tasks: Communicate/share data (the Web, BitTorrent) Compute something together Collectively provide a service 2

A Distributed System 3

Or a Distributed System 4

5 Thesis The wealth of social information exposed from multiple sources can be mined in the design of distributed computing infrastructures: to facilitate improved performance for traditional applications and services; to enable novel applications. Funded by NSF CAREER Award

6 Social Information Connects people through relationships Object centric: use of same objects Person centric: declared relationships or co- participation in events, groups, etc. Social relationships can be translated into: Trust Incentives for resource sharing Shared interest in content …

7 Motivating Application: Socially-aware Call Censor

8 Motivating Application: Data Placement

9 “No 24 in B minor, BWV 869” “Les Bonbons” “ Yellow Submarine” “Les Bonbons” “Yellow Submarine” “Wood Is a Pleasant Thing to Think About” “Wood Is a Pleasant Thing to Think About” The interest-sharing graph G m T (V, E):  V is set of users active during interval T  An edge in E connects users who share at least m file requests within T An Example: Interest Sharing

10 Small Worlds Word co-occurrences Film actors LANL coauthors Internet Web Food web Power grid D. J. Watts and S. H. Strogatz, Collective dynamics of small-world networks. Nature, 393: , 1998 R. Albert and A.-L. Barabási, Statistical mechanics of complex networks, R. Modern Physics 74, 47 (2002).

11 Web Interest-Sharing Graphs 7200s, 50files 3600s, 50files 1800s, 100files 1800s, 10file 300s, 1file

12 DØ Interest-Sharing Graphs 7days, 1file 28 days, 1 file

13 KaZaA Interest-Sharing Graphs 7day, 1file 28 days 1 file 2 hours 1 file 1 day 2 files 4h 2 files 12h 4 files

14 Proactive Information Dissemination D0 Web Kazaa

15 Main Research Questions What social information is relevant to distributed systems design? How to protect private information? How to use social information? What applications and services can benefit from social information?

Relevance to this Collaborative Class? Experience with interdisciplinary work Communication ( e.g., geodesic vs. shortest path) Field-specific problem-solving approach High potential for more interesting research By formulating more interesting questions By access to richer computational tools and expertise Better learning (bigger project, real problems) Team work: can be highly productive – outcome bigger than the sum of the parts. 16

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