8,837 research outputs found
The CEO Problem with Secrecy Constraints
We study a lossy source coding problem with secrecy constraints in which a
remote information source should be transmitted to a single destination via
multiple agents in the presence of a passive eavesdropper. The agents observe
noisy versions of the source and independently encode and transmit their
observations to the destination via noiseless rate-limited links. The
destination should estimate the remote source based on the information received
from the agents within a certain mean distortion threshold. The eavesdropper,
with access to side information correlated to the source, is able to listen in
on one of the links from the agents to the destination in order to obtain as
much information as possible about the source. This problem can be viewed as
the so-called CEO problem with additional secrecy constraints. We establish
inner and outer bounds on the rate-distortion-equivocation region of this
problem. We also obtain the region in special cases where the bounds are tight.
Furthermore, we study the quadratic Gaussian case and provide the optimal
rate-distortion-equivocation region when the eavesdropper has no side
information and an achievable region for a more general setup with side
information at the eavesdropper.Comment: Accepted for publication in IEEE Transactions on Information
Forensics and Security, 17 pages, 4 figure
Secure Multiterminal Source Coding with Side Information at the Eavesdropper
The problem of secure multiterminal source coding with side information at
the eavesdropper is investigated. This scenario consists of a main encoder
(referred to as Alice) that wishes to compress a single source but
simultaneously satisfying the desired requirements on the distortion level at a
legitimate receiver (referred to as Bob) and the equivocation rate --average
uncertainty-- at an eavesdropper (referred to as Eve). It is further assumed
the presence of a (public) rate-limited link between Alice and Bob. In this
setting, Eve perfectly observes the information bits sent by Alice to Bob and
has also access to a correlated source which can be used as side information. A
second encoder (referred to as Charlie) helps Bob in estimating Alice's source
by sending a compressed version of its own correlated observation via a
(private) rate-limited link, which is only observed by Bob. For instance, the
problem at hands can be seen as the unification between the Berger-Tung and the
secure source coding setups. Inner and outer bounds on the so called
rates-distortion-equivocation region are derived. The inner region turns to be
tight for two cases: (i) uncoded side information at Bob and (ii) lossless
reconstruction of both sources at Bob --secure distributed lossless
compression. Application examples to secure lossy source coding of Gaussian and
binary sources in the presence of Gaussian and binary/ternary (resp.) side
informations are also considered. Optimal coding schemes are characterized for
some cases of interest where the statistical differences between the side
information at the decoders and the presence of a non-zero distortion at Bob
can be fully exploited to guarantee secrecy.Comment: 26 pages, 16 figures, 2 table
Artificial-Noise-Aided Secure Multi-Antenna Transmission with Limited Feedback
We present an optimized secure multi-antenna transmission approach based on
artificial-noise-aided beamforming, with limited feedback from a desired
single-antenna receiver. To deal with beamformer quantization errors as well as
unknown eavesdropper channel characteristics, our approach is aimed at
maximizing throughput under dual performance constraints - a connection outage
constraint on the desired communication channel and a secrecy outage constraint
to guard against eavesdropping. We propose an adaptive transmission strategy
that judiciously selects the wiretap coding parameters, as well as the power
allocation between the artificial noise and the information signal. This
optimized solution reveals several important differences with respect to
solutions designed previously under the assumption of perfect feedback. We also
investigate the problem of how to most efficiently utilize the feedback bits.
The simulation results indicate that a good design strategy is to use
approximately 20% of these bits to quantize the channel gain information, with
the remainder to quantize the channel direction, and this allocation is largely
insensitive to the secrecy outage constraint imposed. In addition, we find that
8 feedback bits per transmit antenna is sufficient to achieve approximately 90%
of the throughput attainable with perfect feedback.Comment: to appear in IEEE Transactions on Wireless Communication
The Corporate Criminal as Scapegoat
A corporation is no scapegoat, assures the Department of Justice, because the first priority is to prosecute culpable individuals and not artificial entities. Yet, as I document in this empirical study, far more often than not, when the largest corporations settle federal criminal cases, no individuals are charged. High profile failures to prosecute executives in the wake of the Global Financial Crisis have only made the problem more urgent. The corporation appears to be a kind of a scapegoat: impossible to physically jail, but capable of receiving blame and punishment while individual culprits go free. In this Article, I develop original empirical data detailing the path of individual prosecutions accompanying federal corporate prosecution agreements. Only 34 percent of federal corporate deferred and non-prosecution agreements from 2001-2014 were accompanied by charges against individuals. Those prosecutions produced uneven results. Only 42 percent of those charged received any jail time. There were large numbers of outright losses: 15 percent terminated in acquittals or dismissals. Only a handful of the cases involved high-level executives. These findings illustrate the challenges posed by organizational complexity and the manner in which it can obscure fault. Contrary to the calls of prominent critics, I argue that bringing more individual criminal cases cannot adequately substitute for prosecuting companies. Instead, corporate prosecutions should be leveraged to enhance individual accountability. In conclusion, I propose statutory, sentencing, and policy changes to tighten the connection between individual and corporate accountability for crimes
Testing goodwill: Conflict and co-operation in new product development networks
Network forms are often seen as models of organisational flexibility, promoting the building of trust and exchange of information between different business functions while offering both cost savings and reductions in the uncertainties usually associated with innovation. Both internal and external networks have been identified as key elements in the collaborative development of new products. The actual process of network building and ongoing network management is not well researched, although the existing literature highlights difficulties for organisations attempting to maintain active product development networks. This article examines the development and management of such a network in the defence industry and focuses on network building processes in terms of the interactions between the individuals involved. This network has endured and evolved over many years despite a series of conflicts. One of the key findings is that the effective functioning of the overall network is closely allied to established processes within the two participating firms
Lecture Notes on Network Information Theory
These lecture notes have been converted to a book titled Network Information
Theory published recently by Cambridge University Press. This book provides a
significantly expanded exposition of the material in the lecture notes as well
as problems and bibliographic notes at the end of each chapter. The authors are
currently preparing a set of slides based on the book that will be posted in
the second half of 2012. More information about the book can be found at
http://www.cambridge.org/9781107008731/. The previous (and obsolete) version of
the lecture notes can be found at http://arxiv.org/abs/1001.3404v4/
National security policy constraints on technological innovation: A case study of the Invention Secrecy Act of 1951
Recent studies indicate that the United States is trailing other countries in technological innovation and competitiveness. This case study examined national security policy constraints on technological innovation, specifically the Invention Secrecy Act. It focused on the social constructs of collaboration and interdisciplinary knowledge in the aerospace industry. The methodology included historical research, data collection, and semi-structured interviews with experts from academia, general industry, government and public policy, aerospace/defense industry, and federal government. The results of the study suggested that since World War II, national security policies have not been clearly and consistently defined, interpreted, or implemented. This lack of clarity gave rise to actions by presidential administrations and federal agencies, creating a fractious atmosphere and further limiting access to and sharing of restricted or classified information by academia, industry, government, and private researchers. Government actions also directed funding allocations to specific research types or groups, which added to the veil of secrecy and selectiveness surrounding national security projects. Collectively, the actions constrained collaboration and interdisciplinary exchange of knowledge; two essential sources for technological innovation. This study identified five critical factors that likely impede technological innovation in America’s aerospace industry: (a) power, control, and responsibility for national security, (b) the assumption that technological supremacy equals a secure nation, (c) policy constraints: the Invention Secrecy Act and Export Control Regulations, (d) funding constraints, and (e) organizational culture and ethnocentrism. Recommendations for future studies include explore and identify additional constraints on innovation by other national security policies, investigate and assess the impact of these restrictive policies on specific industries, and examine organizational culture as a barrier to technological innovation
Critical Perspectives Sustainability of the on South African Civil Society Sector
This report presents the findings of a research and advocacy process that included consultative workshops with CSOs in all nine of South Africa's provinces, interviews with CSOs, politicians, government departments, the NLB, NDA and local funders. The report highlights the successes and ongoing problems associated with the NLB and the NDA. It locates them within a broader context of government unevenness, inefficiency and corruption
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