ISSN 0032-9460, Problems of Information Transmission, 2015, Vol. 51, No. 1, pp. 75–81.
Pleiades Publishing, Inc., 2015.
Original Russian Text
O.V. Trushina, E.M. Gabidulin, 2015, published in Problemy Peredachi Informatsii, 2015, Vol. 51, No. 1, pp. 82–89.
A New Method for Ensuring Anonymity and Security
in Network Coding
O. V. Trushina and E. M. Gabidulin
Moscow Institute of Physics and Technology (State University), Moscow, Russia
e-mail: firstname.lastname@example.org, ernst
Received April 18, 2014; in ﬁnal form, November 3, 2014
Abstract—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 ad-
versary 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 ad-
ditional 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.
In , a short description of a method for ensuring anonymity and security in coherent network
coding was given. Here we present a more detailed and extended version.
Network coding  is a new concept of data transmission. If intermediate nodes are allowed to
make some operations on incoming packages, this may improve the throughput and reliability of
networks as compared with traditional transmission methods where intermediate nodes can only
keep and forward incoming packages but cannot make any other operations.
To become an alternative to traditional methods, network coding must maintain a high quality
level of transmission, including data security and privacy. Most of traditional methods of data
protection cannot be used in network coding; they do take into account that packages can be
changed at each intermediate node, which is a key feature of network coding.
Along with ensuring secrecy of transmission, an important information protection problem is
providing privacy of users. Data transmission can be considered as anonymous if a possible ad-
versary cannot establish relations between a sender and a receiver, i.e., determine who transmits
a message and to whom. In particular, anonymity is compromised if the adversary can determine
a route between a source and destination, because the pair source–destination becomes known in
this case. However, making a message route secret is not enough, since wiretapping a message may
also allow the adversary to detect a route.
2. NETWORK CODING
In linear network coding intermediate nodes produce linear combinations of incoming packages.
Message symbols are treated as elements of a ﬁnite ﬁeld. There are two approaches to deﬁne the
Supported in part by the Russian Foundation for Basic Research, project no. 12-07-00122a.