SCoT: a secure content-oriented transport

The evolution of the Internet has resulted in the deployment of new application-level solutions to enhance the scalability and efficiency of content dissemination (e.g., content delivery networks and peer-to-peer systems). However, despite of this improvement on performance, the utilization of this type of solutions introduces new security concerns, as a content provider must necessarily delegate the role of distributing the content to third parties, and current security solutions, such as TLS and IPsec, do not allow authenticating the original content provider or the content itself in these scenarios. In this paper, we present SCoT, a transport-layer protocol that allows a content provider to bind protection to content, enabling content authentication at receivers regardless of any third party infrastructures that have been used to disseminate the content. Content authentication procedures are executed transparently to end-user applications. We implemented a fully operational prototype of the protocol in Java, including an API to support the development of SCoT applications. We utilized it to configure an experimentation scenario that served to validate a theoretical analysis of the SCoT throughput and to illustrate the performance that can be achieved in a practical deployment. The paper concludes describing a set of use cases of the protocol.This article has been partially supported by the European H2020 5Gin-FIRE project (grant agreement 732497), and by the DRONEXT project (TEC2014-54335-C4-2-R) funded by the Spanish Ministry of Economy and Competitiveness. The work of Ignacio Soto has partially been supported by the Spanish Texeo project (TEC2016-80339-R) funded by the Spanish Ministry of Economy and Competitiveness

Planck 2018 results : X. Constraints on inflation

We report on the implications for cosmic inflation of the 2018 release of the Planck cosmic microwave background (CMB) anisotropy measurements. The results are fully consistent with those reported using the data from the two previous Planck cosmological releases, but have smaller uncertainties thanks to improvements in the characterization of polarization at low and high multipoles. Planck temperature, polarization, and lensing data determine the spectral index of scalar perturbations to be n(s)=0.9649 +/- 0.0042 at 68% CL. We find no evidence for a scale dependence of n(s), either as a running or as a running of the running. The Universe is found to be consistent with spatial flatness with a precision of 0.4% at 95% CL by combining Planck with a compilation of baryon acoustic oscillation data. The Planck 95% CL upper limit on the tensor-to-scalar ratio, r(0.002)<0.10, is further tightened by combining with the BICEP2/Keck Array BK15 data to obtain r(0.002)<0.056. In the framework of standard single-field inflationary models with Einstein gravity, these results imply that: (a) the predictions of slow-roll models with a concave potential, V(phi) <0, are increasingly favoured by the data; and (b) based on two different methods for reconstructing the inflaton potential, we find no evidence for dynamics beyond slow roll. Three different methods for the non-parametric reconstruction of the primordial power spectrum consistently confirm a pure power law in the range of comoving scales 0.005 Mpc(-1)k less than or similar to 0.2 Mpc(-1). A complementary analysis also finds no evidence for theoretically motivated parameterized features in the Planck power spectra. For the case of oscillatory features that are logarithmic or linear in k, this result is further strengthened by a new combined analysis including the Planck bispectrum data. The new Planck polarization data provide a stringent test of the adiabaticity of the initial conditions for the cosmological fluctuations. In correlated, mixed adiabatic and isocurvature models, the non-adiabatic contribution to the observed CMB temperature variance is constrained to 1.3%, 1.7%, and 1.7% at 95% CL for cold dark matter, neutrino density, and neutrino velocity, respectively. Planck power spectra plus lensing set constraints on the amplitude of compensated cold dark matter-baryon isocurvature perturbations that are consistent with current complementary measurements. The polarization data also provide improved constraints on inflationary models that predict a small statistically anisotropic quadupolar modulation of the primordial fluctuations. However, the polarization data do not support physical models for a scale-dependent dipolar modulation. All these findings support the key predictions of the standard single-field inflationary models, which will be further tested by future cosmological observations.Peer reviewe

A Passive Influence Model for Adapting Environments based on Semantic Preferences

Peer reviewe

Provenance matters: variability under saline stress in young plants of four populations of a Prosopis (mesquite) species from dry forests of Argentina

Planting of native perennial woody species tolerant to variable salt concentrations can facilitate the recovery of degraded dry forests. The objective was to evaluate and compare the response to saline stress on experimentally controlled conditions of young plants from four provenances of Prosopis alba, a mesquite species useful for restoration plans. They were from different localities of the Chaco Region of Argentina (Santiago del Estero, Chaco, Formosa and Salta) and were evaluated for 45 days under greenhouse controlled growth conditions at 0, 100 and 300 mM NaCl. We measured variables associated with growth, photosynthesis and redox state. The imposed salt stress condition did not cause plant death in any provenance. However, salinity produced a strong effect on growth and physiological variables of all provenances. Salta provenance was associated to higher net values of biomass and stem diameter. Chaco registered the greatest relative values of height and stem diameter, indicating a higher salinity tolerance than the other provenances; also it produced more antioxidants, to cope with the oxidative stress associated to saline stress. Chaco and Salta could be the most promising provenances to use in restoration plans of dry forests in areas with saline soils in the Chaco region. We emphasize the importance of use different provenances in forest restoration for a more successful system recovery.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author