With the increasingly ubiquitous nature of Social networks and Cloud computing, users are starting to explore new ways to interact with, and exploit these developing paradigms. Social networks are used to reflect real world relationships that allow users to share information and form connections between one another, essentially creating dynamic Virtual Organizations. We propose leveraging the pre-established trust formed through friend relationships within a Social network to form a dynamic “Social Cloud”, enabling friends to share resources within the context of a Social network. We believe that combining trust relationships with suitable incentive mechanisms (through financial payments or bartering) could provide much more sustainable resource sharing mechanisms. This paper outlines our vision of, and experiences with, creating a Social Storage Cloud, looking specifically at possible market mechanisms that could be used to create a dynamic Cloud infrastructure in a Social network environment.

1. Social Cloud: Cloud Computing in Social
Networks
Kyle Chard, Simon Caton, Omer Rana
and Kris Bubendorfer

2. Emerging Themes
• Cloud Computing is growing in strength
– Many providers e.g. Amazon EC2/S3, Google App
Engine, Microsoft Azure and also many smaller
scale open clouds such as Nimbus and Eucalyptus.
• Social Networking is increasingly ubiquitous:
– E.g. Facebook has over 400 Million active users.
– 50 % of these users log on every day

3. Current Cloud Scenarios and Problems
• Sharing
– Finite capacity vs. fluctuating requirements
– Many social peers with different capabilities
• Economy
– Small scale consumers have ad hoc requirements
– Money grabbing providers and inflexible lock-in
• Trust
– always assumed at some level
– Anonymity (Market-based/broker allocation)
– Many models fall apart when this is removed

4. Social Networks
• Formed through pre-existing relationships,
– i.e. your friends
• Have a pre-existent fabric of trust inherently
interwoven into the network
– How many of your friends do you not trust?
• Many applications now use social networks as a
platform for:
– Authentication e.g. Facebook Connect
– Application Portals e.g. ASPEN and PolarGrid projects
• There already exist well established application
APIs

5. The Social Cloud Vision
+ +
The leveraging of pre-existing
relationships in order to enable A Social Cloud allows friends to share
mutually beneficial interactions capabilities within the context of a
within a cloud context. Social Network.
• An amalgamation of:
Volunteer computing arises as users
– Social Networking can share resources for little or no
– Cloud Computing gain, perhaps through reciprocal
– Volunteer Computing arrangements.

6. Social Cloud Interaction Vision
Socially –
orientated
Market
Place
Social Cloud

7. Social Cloud Economy
• Payment (in an economic sense) is optional
• Instead we utilise a virtual currency
– All collaborations involve a transfer of “credits”
– All participants are given an initial amount of
credits
– No one can buy additional credits – they must be
earned
– Therefore, we can prevent free-riding, and actively
encourage participation

8. Community Effect
• Susceptible to cheating through fabricated
accounts
– Social Enforcement: exclusion of anti-social peers
• To encapsulate the nature of an interaction an
agreement is used for the domains:
– Technical Requirements
– Non-functional properties
– Temporal Requirements
– Economic preferences
• WS-Agreement + EJSDL + DRIVE API + Reservation
+ Social Cloud Extensions

9. Social Cloud Proof of Concept
• Simple Storage Service Implemented as a
Facebook application
• Use Case: a back up facility
Agreement

10. Posted Price
– Enables interactions based upon active trading/collaborative
decisions
– Intuitively facilitates reciprocal collaboration
– Current “norm” in industry solutions
Social Cloud
MDS
User ID URL Capacity Price
User1 100MB 5 Storage
Storage
User2 500MB 10 Storage
User3 5GB 7

11. Dynamic Auctions
• Auction:
– Enables dynamic participant pairing
– Sealed bid second price reverse auction
• Could be extended to any other auction mechanism

12. Evaluation
Research Questions:
• Can a Social Cloud Scale?
• What are the computational requirements for
an “average” sized Social Cloud?
– According to Facebook, the average social
network has 130 participants
• Can a Social Cloud function in a timely manner
as a Facebook application?

13. Posted Price Scalability
• Varying the size of the MDS and number of matches
• With a size of 2000, 100 matches can be discovered
in ~ 2 seconds, which is reasonable

14. Auction Scalability
• 500 Auctions and the worst case scenario:
– all auctions run concurrently
• Even with 50 bidders can still complete 65 auctions per
minute
• Under our assumptions this is already enough for a large
social network

15. Dissemination of Results
• A social (storage) cloud can be hosted using
minimal resources (3 – 4 yr old PC)
• Components show good throughput under
realistic loads
• However, scaling to millions of users would
require a dedicated HPC or elastic
environment
– Co-op model  members sustain the platform

16. Conclusions & Future Work
• Social Cloud
– Dynamic cloud environment leveraging existing trust
relationships
– Proof-of-concept: can be extended for many new
scenarios
• Future Work
– Computation, licenses and other capabilities
– Combinatorial auctions
– Generic scientific cloud communities – e.g.
myExperiment
– Evolution of the economic model

17. Questions?
Please look at our Prototype Social Cloud Video
http://www.im.uni-karlsruhe.de/SocialCloudDemo
Kyle@ecs.vuw.ac.nz / kyle@ci.uchicago.edu
Simon.Caton@kit.edu
O.F.Rana@cs.cardiff.ac.uk
Kris.Bubendorfer@ecs.vuw.ac.nz