A new method for ensuring anonymity and security in network coding

We propose a method for providing anonymity and security of data transmission in networks with network coding with multiple sources and receivers. An external passive adversary is assumed to be present in the network. It is required to organize message transmission in such a manner that the adversary cannot trace a message route. The proposed method is a modification of a secure transmission scheme based on coset coding. We show that using an additional operation at relaying nodes enables to remove statistical dependence between incoming and outgoing messages of the relaying nodes. This makes tracing message routes impossible. An overlay network between a source and a receiver must be constructed due to restrictions on routes between the source and receiver: the minimum cut between two successive nodes must be not less than the number of packets in the encoded source message.