2,034 research outputs found
Stochastic Dynamic Cache Partitioning for Encrypted Content Delivery
In-network caching is an appealing solution to cope with the increasing
bandwidth demand of video, audio and data transfer over the Internet.
Nonetheless, an increasing share of content delivery services adopt encryption
through HTTPS, which is not compatible with traditional ISP-managed approaches
like transparent and proxy caching. This raises the need for solutions
involving both Internet Service Providers (ISP) and Content Providers (CP): by
design, the solution should preserve business-critical CP information (e.g.,
content popularity, user preferences) on the one hand, while allowing for a
deeper integration of caches in the ISP architecture (e.g., in 5G femto-cells)
on the other hand.
In this paper we address this issue by considering a content-oblivious
ISP-operated cache. The ISP allocates the cache storage to various content
providers so as to maximize the bandwidth savings provided by the cache: the
main novelty lies in the fact that, to protect business-critical information,
ISPs only need to measure the aggregated miss rates of the individual CPs and
do not need to be aware of the objects that are requested, as in classic
caching. We propose a cache allocation algorithm based on a perturbed
stochastic subgradient method, and prove that the algorithm converges close to
the allocation that maximizes the overall cache hit rate. We use extensive
simulations to validate the algorithm and to assess its convergence rate under
stationary and non-stationary content popularity. Our results (i) testify the
feasibility of content-oblivious caches and (ii) show that the proposed
algorithm can achieve within 10\% from the global optimum in our evaluation
MANAGING KNOWLEDGE AND DATA FOR A BETTER DECISION IN PUBLIC ADMINISTRATION
In the current context, the society is dominated by the rapid development of computer networks and the integration of services and facilities offered by the Internet environment at the organizational level. The success of an organization depends largely on the quality and quantity of information it has available to develop quickly decisions able to meet the current needs. The need for a collaborative environment within the central administration leads to the unification of resources and instruments around the Center of Government, to increase both the quality and efficiency of decision - making, especially reducing the time spent with decision - making, and upgrading the decision â making act.administration, strategy, decision, complex systems, management, infrastructure, e-government, information society, government platform.
LiS: Lightweight Signature Schemes for continuous message authentication in cyber-physical systems
Agency for Science, Technology and Research (A*STAR) RIE 202
Analysis of the largest tandemly repeated DNA families in the human genome
<p>Abstract</p> <p>Background</p> <p>Tandemly Repeated DNA represents a large portion of the human genome, and accounts for a significant amount of copy number variation. Here we present a genome wide analysis of the largest tandem repeats found in the human genome sequence.</p> <p>Results</p> <p>Using Tandem Repeats Finder (TRF), tandem repeat arrays greater than 10 kb in total size were identified, and classified into simple sequence e.g. GAATG, classical satellites e.g. alpha satellite DNA, and locus specific VNTR arrays. Analysis of these large sequenced regions revealed that several "simple sequence" arrays actually showed complex domain and/or higher order repeat organization. Using additional methods, we further identified a total of 96 additional arrays with tandem repeat units greater than 2 kb (the detection limit of TRF), 53 of which contained genes or repeated exons. The overall size of an array of tandem 12 kb repeats which spanned a gap on chromosome 8 was found to be 600 kb to 1.7 Mbp in size, representing one of the largest non-centromeric arrays characterized. Several novel megasatellite tandem DNA families were observed that are characterized by repeating patterns of interspersed transposable elements that have expanded presumably by unequal crossing over. One of these families is found on 11 different chromosomes in >25 arrays, and represents one of the largest most widespread megasatellite DNA families.</p> <p>Conclusion</p> <p>This study represents the most comprehensive genome wide analysis of large tandem repeats in the human genome, and will serve as an important resource towards understanding the organization and copy number variation of these complex DNA families.</p
Coupled-Oscillator Associative Memory Array Operation for Pattern Recognition
Operation of the array of coupled oscillators underlying the associative memory function is demonstrated for various interconnection schemes (cross-connect, star phase keying and star frequency keying) and various physical implementation of oscillators (van der Pol, phase-locked loop, spin torque). The speed of synchronization of oscillators and the evolution of the degree of matching is studied as a function of device parameters. The dependence of errors in association on the number of the memorized patterns and the distance between the test and the memorized pattern is determined for Palm, Furber and Hopfield association algorithms
Janus: Privacy-Preserving Billing for Dynamic Charging of Electric Vehicles
Dynamic charging is an emerging technology that
allows an electric vehicle (EV) to charge its battery while moving
along the road. Dynamic charging charges the EVâs battery
through magnetic induction between the receiving coils attached
to the EVâs battery and the wireless charging pads embedded
under the roadbed and operated by Pad Owners (POs). A key
challenge in dynamic charging is billing, which must consider
the fact that the charging service happens while the EV is
moving on the road, and should allow for flexible usage plans.
A promising candidate could be the subscription-based billing
model, in which an EV subscribes to an electric utility that has
a business relationship with various POs that operate charging
sections. The POs report charging information to the utility of
the EV, and at the end of each billing cycle, the EV receives a
single bill for all its dynamic charging sessions from the utility.
Overshadowing its advantages, a major shortcoming of such
a solution is that the utility gets access to the EVsâ mobility
information, invading thus the location privacy of the EVs.
To enable subscription based billing for dynamic charging, in
this paper we propose Janus, a privacy-preserving billing protocol
for dynamic EV charging. Janus uses homomorphic commitment
and blind signatures with attributes to construct a cryptographic
proof on the charging fee of each individual dynamic charging
session, and allows the utility to verify the correctness of the EVâs
total bill without learning the time, the location, or the charging
fee of each individual charging session of the EV. Our Pythonbased
implementation shows that the real-time computational
overhead of Janus is less than 0.6 seconds, which is well within
the delay constraint of the subscription-based billing model, and
makes Janus an appealing solution for future dynamic charging
applications.Department of Energy/DE-OE0000780Ope
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