Resilient Network Embeddings for Friend-to-Friend Networks

• Applicant: Professor Dr. Thorsten Strufe
• Subject Area: Security and Dependability, Operating-, Communication- and Distributed Systems
• Term: from 2013 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 231189459

Anonymous, censorship-resistant communication is a means to protect the import basic rights of freedom of speech and privacy. Anonymous communication systems have been researched for 30 years, but thequestion, how one can technically realize anonymous communication is nowadays more import than ever in the face of advancing dissemination of data collection and survelliance infrastructures in communicationnetworks. A promising approach towards anonymous communication is the construction of communication systems based on friend-to-friend networks (also called darknets), i.e. overlay networks, in which direct network links can only be established between mutually trusted nodes. Trust between nodes is only assumed where there is trust between the node operators outside the system. By restricting the network topology to the trust graph and by using source rewriting the disclosure of a node's identity is limited to trusted nodes. Therewith membership in a friend-to-friend network is concealed as far as possible and prosecution as well as censorship (e.g. by identification of participants as well as targeted denial-of-service attacks) areimpeded.Based on friend-to-friend networks a variety of anonymous (or pseudonymous), censorship-resistant applications can be build in the future, e.g., distributed publication and data storage services,decentralized online social network services, services for the anonymous Internet access et cetera.To realize a friend-to-friend network an efficient routing procedure based on an addressing scheme is needed. As the network topology of a friend-to-friend network is predetermined by the trust relationshipsand not adaptable towards the requirements of a routing procedure, the only remaining degree of freedom is the adaptation of the address-to-node assignment to the netwok topology by a network embedding algorithm. Using the assigned addresses a routing procedure based on local information only (e.g. greedy routing) can be used for message transfer. Due to the communication restrictions in the friend-to-friend network and due to scalability reasons the embedding and routing have to be realized as decentralized distributed algorithms.In this project network embedding procedures for friend-to-friend networks are to be developed, which enable an efficient routing, offer scalability for global overlay networks and can be realized as decentralized distributed algorithms. Furthermore, the embedding procdures should fulfill requirements regarding privacy preservation, robustness, attack resilience and application-specific requirements. This leads to a set of research problems in the areas of design and analysis of network algorithms as well as modelling and performance evaluation of overlay networks.

• DFG Programme: Research Grants