Enhancing Security and Privacy in Online Social Networks Sonia Jahid sjahid2@illinois.edu University...

Enhancing Security and Privacy in Online

Social Networks

Sonia Jahidsjahid2@illinois.edu

University of Illinois at Urbana-Champaign

PhD Forum

Online Social Network (OSN)

Motivating Examples

Our Goal …

A Private and Secure Online Social NetworkA Private and Secure Online Social Network

Shift the access enforcement point from the provider to the users

Shift the access enforcement point from the provider to the users

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Decentralization

ProviderProvider Trusted Party

Myself

Hybrid

Untrusted Party

• Availability• Access control by others• Confidentiality/Integrity• Malicious activities

WallWallStatusStatus

CommentComment

VideoVideo

LinkLink

Complicated OSN Data

and Access Control

Complicated OSN Data

and Access Control

• Access Control– Attribute-based encryption with efficient

revocation

• Architecture Design– Distributed hash table– Object oriented data– Efficient algorithm for newsfeed

Our Contribution

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EASiER – ASIACCS 2011, DECENT – SESOC 2012, CACHET – CoNEXT 2012

Example

GHC Rocks!

Friend|Alice|Friend

Reference

Alice’s Status

Bob’s Comment

Read

Write/Delete

Append

Application?

Our Goal

• Health Information Exchange– Patient-centric health data through a secure

distributed storage service

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Challenges

• Confidentiality, Integrity, Availability• Private Audit• Anonymous search• Break the glass policy

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Private Audit

• Properties– Authentication– Access Control– Auditing– Anonymity

• Concept– Revocable

Anonymity

StorageStorage

Data

Data

Access

Access

A0danc*#-3948sk3m4lksfmÂp

A0danc*#-3948sk3m4lksfmÂp

Logging Information

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Doctor

Nurse

Anonymous Search

• Properties– Anonymity– Efficiency– Correctness

• Concept– Public Key Encryption

Keyword-based search– Private Information

Retrieval

StorageStorage

Alice, Lab

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Break the Glass Policy

• Properties– Emergency access on

data– Auditing

Alice’s Data

Alice’s Data

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Research Summary

• Techniques to enhance security and privacy of a social network

• Challenges and application of such techniques in healthcare domain

Sonia Jahidhttp://www.soniajahid.comsjahid2@illinois.edu

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