Practical LDPC coded modulation schemes for the fading broadcast channel with confidential messages

The broadcast channel with confidential messages is a well studied scenario from the theoretical standpoint, but there is still lack of practical schemes able to achieve some fixed level of reliability and security over such a channel. In this paper, we consider a quasi-static fading channel in which both public and private messages must be sent from the transmitter to the receivers, and we aim at designing suitable coding and modulation schemes to achieve such a target. For this purpose, we adopt the error rate as a metric, by considering that reliability (security) is achieved when a sufficiently low (high) error rate is experienced at the receiving side. We show that some conditions exist on the system feasibility, and that some outage probability must be tolerated to cope with the fading nature of the channel. The proposed solution exploits low-density parity-check codes with unequal error protection, which are able to guarantee two different levels of protection against noise for the public and the private information, in conjunction with different modulation schemes for the public and the private message bits.Comment: 6 pages, 4 figures, to be presented at IEEE ICC'14 - Workshop on Wireless Physical Layer Securit

LDPC coded transmissions over the Gaussian broadcast channel with confidential messages

We design and assess some practical low-density parity-check (LDPC) coded transmission schemes for the Gaussian broadcast channel with confidential messages (BCC). This channel model is different from the classical wiretap channel model as the unauthorized receiver (Eve) must be able to decode some part of the information. Hence, the reliability and security targets are different from those of the wiretap channel. In order to design and assess practical coding schemes, we use the error rate as a metric of the performance achieved by the authorized receiver (Bob) and the unauthorized receiver (Eve). We study the system feasibility, and show that two different levels of protection against noise are required on the public and the secret messages. This can be achieved in two ways: i) by using LDPC codes with unequal error protection (UEP) of the transmitted information bits or ii) by using two classical non-UEP LDPC codes with different rates. We compare these two approaches and show that, for the considered examples, the solution exploiting UEP LDPC codes is more efficient than that using non-UEP LDPC codes.Comment: 5 pages, 5 figures, to be presented at IEEE ICT 201

A Survey of Physical Layer Security Techniques for 5G Wireless Networks and Challenges Ahead

Physical layer security which safeguards data confidentiality based on the information-theoretic approaches has received significant research interest recently. The key idea behind physical layer security is to utilize the intrinsic randomness of the transmission channel to guarantee the security in physical layer. The evolution towards 5G wireless communications poses new challenges for physical layer security research. This paper provides a latest survey of the physical layer security research on various promising 5G technologies, including physical layer security coding, massive multiple-input multiple-output, millimeter wave communications, heterogeneous networks, non-orthogonal multiple access, full duplex technology, etc. Technical challenges which remain unresolved at the time of writing are summarized and the future trends of physical layer security in 5G and beyond are discussed.Comment: To appear in IEEE Journal on Selected Areas in Communication

Security gap analysis of some LDPC coded transmission schemes over the flat and fast fading Gaussian wire-tap channels

n/

NB-JNCD Coding and Iterative Joint Decoding Scheme for a Reliable communication in Wireless sensor Networks with results

Privacy threat is a very serious issue in multi-hop wireless networks (MWNs) since open wireless channels are vulnerable to malicious attacks. A distributed random linear network coding approach for transmission and compression of information in general multisource multicast networks. Network nodes independently and randomly select linear mappings from inputs onto output links over some field. Network coding has the potential to thwart traffic analysis attacks since the coding/mixing operation is encouraged at intermediate nodes. However, the simple deployment of network coding cannot achieve the goal once enough packets are collected by the adversaries. This paper proposes non-binary joint network-channel coding for reliable communication in wireless networks. NB-JNCC seamlessly combines non-binary channel coding and random linear network coding, and uses an iterative two-tier coding scheme that weproposed to jointly exploit redundancy inside packets and across packets for error recovery

An Overview of Physical Layer Security with Finite-Alphabet Signaling

Providing secure communications over the physical layer with the objective of achieving perfect secrecy without requiring a secret key has been receiving growing attention within the past decade. The vast majority of the existing studies in the area of physical layer security focus exclusively on the scenarios where the channel inputs are Gaussian distributed. However, in practice, the signals employed for transmission are drawn from discrete signal constellations such as phase shift keying and quadrature amplitude modulation. Hence, understanding the impact of the finite-alphabet input constraints and designing secure transmission schemes under this assumption is a mandatory step towards a practical implementation of physical layer security. With this motivation, this article reviews recent developments on physical layer security with finite-alphabet inputs. We explore transmit signal design algorithms for single-antenna as well as multi-antenna wiretap channels under different assumptions on the channel state information at the transmitter. Moreover, we present a review of the recent results on secure transmission with discrete signaling for various scenarios including multi-carrier transmission systems, broadcast channels with confidential messages, cognitive multiple access and relay networks. Throughout the article, we stress the important behavioral differences of discrete versus Gaussian inputs in the context of the physical layer security. We also present an overview of practical code construction over Gaussian and fading wiretap channels, and we discuss some open problems and directions for future research.Comment: Submitted to IEEE Communications Surveys & Tutorials (1st Revision

Principles of Physical Layer Security in Multiuser Wireless Networks: A Survey

This paper provides a comprehensive review of the domain of physical layer security in multiuser wireless networks. The essential premise of physical-layer security is to enable the exchange of confidential messages over a wireless medium in the presence of unauthorized eavesdroppers without relying on higher-layer encryption. This can be achieved primarily in two ways: without the need for a secret key by intelligently designing transmit coding strategies, or by exploiting the wireless communication medium to develop secret keys over public channels. The survey begins with an overview of the foundations dating back to the pioneering work of Shannon and Wyner on information-theoretic security. We then describe the evolution of secure transmission strategies from point-to-point channels to multiple-antenna systems, followed by generalizations to multiuser broadcast, multiple-access, interference, and relay networks. Secret-key generation and establishment protocols based on physical layer mechanisms are subsequently covered. Approaches for secrecy based on channel coding design are then examined, along with a description of inter-disciplinary approaches based on game theory and stochastic geometry. The associated problem of physical-layer message authentication is also introduced briefly. The survey concludes with observations on potential research directions in this area.Comment: 23 pages, 10 figures, 303 refs. arXiv admin note: text overlap with arXiv:1303.1609 by other authors. IEEE Communications Surveys and Tutorials, 201