Abstract: A distributed communication and data sharing system that provides anonymity and unlinkability. A group comprising a number of structures, each having a public/private key pair, is stored on a plurality of nodes in a Distributed Hash Table. Advantageous features of the group management system are provided through the use of Cryptographically Generated Addresses (CGA) for the structures, a secure capture method that enables a user to capture an address and be the only one authorized to request certain operations for the address, and an anonymous get/set mechanism in which a user signs messages, encloses the public key in the message and encrypts the message and public key using the public key of the receiver. The distributed communication and data sharing system of the invention can advantageously be used for group management of social networks.

Abstract: The present invention generally relates to distributed data storage systems. In particular, the present invention relates to a method of data placement in a distributed data storage system that combines high data availability with a low impact on network and data storage resources, in terms of bandwidth needed for exchange of data between network nodes and in terms of number of network nodes needed to store an item of data.

Abstract: The present invention generally relates to distributed data storage systems. In particular, the present invention relates to optimization of the distributed storage system in terms of number of data replicas needed to ensure a desired level of data replication.

Abstract: A method for determining the dynamics of a logical network, said network comprising a plurality of communication nodes (21, 24, 26, i, k). The method comprises obtaining (31), in a node (21) of the network, of at least one item of information (Li, Jk) relating to a modification of the neighborhood of said node, in the course of a predetermined period. The method also comprises determining (33), in said node of the network, of a local dynamics corresponding to at least one sum ( ? i ? L ? ? i , ? k ? J ? ? k ) of at least part of the information obtained.

Abstract: A method for determining the dynamics of a logical network, said network comprising a plurality of communication nodes (21, 24, 26, i, k). The method comprises obtaining (31), in a node (21) of the network, of at least one item of information (Li, Jk) relating to a modification of the neighborhood of said node, in the course of a predetermined period. The method also comprises determining (33), in said node of the network, of a local dynamics corresponding to at least one sum ( ? i ? L ? ? i , ? k ? J ? ? k ) of at least part of the information obtained.

Abstract: A system for establishing a client/server type relationship in a hybrid peer to peer network connects a first peer (20a) to a second peer (20d) implementing a predetermined function (F) in that peer to peer network. To this end, the first peer (20a) has a superpeer (10a) capable of establishing a list (LF) of the active peers (20d, 20e) implementing the function (F) in the service of the peers of the network and of sending that list (LF) to its peer (20a). The first peer (20a) can then establish a client/server type relationship with a second peer (20d) selected in that list (LF).

Abstract: A method for managing a database in a communication network comprising the following steps: at least some of a segment to be copied from the database is copied to a copied segment; at least one node which is part of the communication network and intended to receive the copied segment is selected; wherein the node is selected on the basis of a capacity information item which is characteristic of it.