STOC '97 Proceedings of the twenty-ninth annual ACM symposium on Theory of computing
A digital fountain approach to reliable distribution of bulk data
Proceedings of the ACM SIGCOMM '98 conference on Applications, technologies, architectures, and protocols for computer communication
Tangler: a censorship-resistant publishing system based on document entanglements
CCS '01 Proceedings of the 8th ACM conference on Computer and Communications Security
Tarzan: a peer-to-peer anonymizing network layer
Proceedings of the 9th ACM conference on Computer and communications security
Infranet: Circumventing Web Censorship and Surveillance
Proceedings of the 11th USENIX Security Symposium
Traffic Analysis Attacks and Trade-Offs in Anonymity Providing Systems
IHW '01 Proceedings of the 4th International Workshop on Information Hiding
Mixminion: Design of a Type III Anonymous Remailer Protocol
SP '03 Proceedings of the 2003 IEEE Symposium on Security and Privacy
Location diversity in anonymity networks
Proceedings of the 2004 ACM workshop on Privacy in the electronic society
Low-Cost Traffic Analysis of Tor
SP '05 Proceedings of the 2005 IEEE Symposium on Security and Privacy
Tor: the second-generation onion router
SSYM'04 Proceedings of the 13th conference on USENIX Security Symposium - Volume 13
Low-resource routing attacks against tor
Proceedings of the 2007 ACM workshop on Privacy in electronic society
A web based covert file system
HOTOS'07 Proceedings of the 11th USENIX workshop on Hot topics in operating systems
Towards an information theoretic metric for anonymity
PET'02 Proceedings of the 2nd international conference on Privacy enhancing technologies
Fingerprinting websites using traffic analysis
PET'02 Proceedings of the 2nd international conference on Privacy enhancing technologies
Pass it on: social networks stymie censors
IPTPS'08 Proceedings of the 7th international conference on Peer-to-peer systems
Circumventing censorship with collage
Proceedings of the ACM SIGCOMM 2010 conference
A framework for avoiding steganography usage over HTTP
Journal of Network and Computer Applications
Scrambling for lightweight censorship resistance
SP'11 Proceedings of the 19th international conference on Security Protocols
Proximax: measurement-driven proxy dissemination (short paper)
FC'11 Proceedings of the 15th international conference on Financial Cryptography and Data Security
SkypeMorph: protocol obfuscation for Tor bridges
Proceedings of the 2012 ACM conference on Computer and communications security
StegoTorus: a camouflage proxy for the Tor anonymity system
Proceedings of the 2012 ACM conference on Computer and communications security
CensorSpoofer: asymmetric communication using IP spoofing for censorship-resistant web browsing
Proceedings of the 2012 ACM conference on Computer and communications security
Making sense of internet censorship: a new frontier for internet measurement
ACM SIGCOMM Computer Communication Review
POSTER: Identity-based steganography and its applications to censorship resistance
Proceedings of the 2013 ACM SIGSAC conference on Computer & communications security
EFFORT: A new host-network cooperated framework for efficient and effective bot malware detection
Computer Networks: The International Journal of Computer and Telecommunications Networking
Protocol misidentification made easy with format-transforming encryption
Proceedings of the 2013 ACM SIGSAC conference on Computer & communications security
Message in a bottle: sailing past censorship
Proceedings of the 29th Annual Computer Security Applications Conference
Validating web content with senser
Proceedings of the 29th Annual Computer Security Applications Conference
| Hi-index | 0.00 |
Oppressive regimes and even democratic governments restrict Internet access. Existing anti-censorship systems often require users to connect through proxies, but these systems are relatively easy for a censor to discover and block. This paper offers a possible next step in the censorship arms race: rather than relying on a single system or set of proxies to circumvent censorship firewalls, we explore whether the vast deployment of sites that host user-generated content can breach these firewalls. To explore this possibility, we have developed Collage, which allows users to exchange messages through hidden channels in sites that host user-generated content. Collage has two components: a message vector layer for embedding content in cover traffic; and a rendezvous mechanism to allow parties to publish and retrieve messages in the cover traffic. Collage uses user-generated content (e.g., photo-sharing sites) as "drop sites" for hidden messages. To send a message, a user embeds it into cover traffic and posts the content on some site, where receivers retrieve this content using a sequence of tasks. Collage makes it difficult for a censor to monitor or block these messages by exploiting the sheer number of sites where users can exchange messages and the variety of ways that a message can be hidden. Our evaluation of Collage shows that the performance overhead is acceptable for sending small messages (e.g., Web articles, email). We show how Collage can be used to build two applications: a direct messaging application, and a Web content delivery system.