Intrinsic Information of Wideband Channels

Abstract

Abstract-The ability to exchange secret messages and protect against security attacks becomes increasingly important for providing information superiority and confidentiality in modern information systems. These systems require shared secret keys, which can be generated from common random sources with known distributions. However, the assumption on the distribution of the sources may not hold in many realistic scenarios. In this paper, we establish a mathematical framework for secret-key generation using common unknown deterministic sources (UDSs). In particular, we propose a new information measure called intrinsic information to characterize the achievable length of the secret key that can be generated from a UDS. As a case study, we consider a wideband propagation medium in mobile wireless networks as a UDS and derive its intrinsic information as a function of various network parameters. Our results provide a non-Bayesian perspective for secret-key generation as well as practical implications of this new perspective.

Wireless Network Intrinsic Secrecy

“…For a given and , the secrecy throughput of the legitimate link associated with the th transmitter, conditioned on , is given by (30) Similar to the conditional network secrecy rate defined in Section III-B, the conditional network secrecy throughput originated from the legitimate nodes in a bounded set is defined as (31) Then, the network secrecy throughput density is given by (32) which results in (33) In (33), is the average secrecy throughput of a typical link in the network with the legitimate transmitter placed in the origin. Specifically, we can write 18 (34) The evaluation of network secrecy metrics, given by (20), (24), and (33), requires the statistical characterization of and , whose CDF and PDF are derived in the following.…”

“…and follow a uniform distribution in . Therefore, the CDF of becomes (55) Letting , the CDF of the maximum SIR becomes (56) Using (56) together with the results in Section V, the network secrecy rate density (20), the network secrecy rate outage density (24), and the network secrecy throughput density (33) are obtained for the case of NERN strategy.…”

“…25 Replacing and with and , and using the results in Section V, the network secrecy rate density (20), the network secrecy rate outage density (24), and the network secrecy throughput density (33) are obtained for the ENIS strategy.…”

“…Secrecy capacity has been further studied in the context of multiple-access channels [14]- [16], broadcast channels [17]- [19], artificial noise [20], eavesdropper collusion [21]- [23], point-to-point diversity communications [24]- [27], and cooperative communications [28]. The generation of secret keys at the physical layer using common sources, such as reciprocal wireless channels, is addressed in [29]- [33].…”

Distributed Network Secrecy

“…Secret-key generation at the physical-layer using common sources, such as reciprocal wireless channels, has been investigated in [26]- [30]. In addition, secrecy in clustered or multi-hop networks has been investigated in [31]- [33].…”