arXiv subjects

Pino Caballero-Gil

Publications and source records attributed to Pino Caballero-Gil.

At least 19 recordsLinked to original sources

arXiv2026

Shaping Opinion: Quantifying the Psychological Impact of Autonomous Multi-Agent LLM Interactions

Natural-sounding multi-agent conversational AI is increasingly deployed, fundamentally altering human-machine interaction and human information processing. While prior work largely focuses on algorithmic failure, this study investigates the cognitive ergonomics and socio-cognitive impact of algorithmic competence. We present and evaluate FORMS (Framework for Opinion and Rhetoric in Multi-agent Simulations), a low-latency architecture for spatially mediated human-machine dialogue, driven by distinct LLM-based personas and real-time concurrency resolution. To conduct a system test and evaluation of its psychological impact, we exposed an adolescent cohort (n=120) and an adult pilot group (n=25) to a live, moderated synthetic debate. Our findings reveal that exposure to highly competent multi-agent systems triggers "Cognitive Destabilization," fragmenting users' prior strategic consensus. Concurrently, we observe a "Regulatory Awakening" driven by the "Normality Paradox": fluid human-machine interactions inherently increase the baseline demand for external regulation. Furthermore, our pilot study suggests the presence of a "Truthfulness Paradox": despite understanding the risks of generative AI, participants in the adult cohort rated the synthetic debate as significantly more sincere than equivalent human discourse (Cohen's d=2.04). Supported by robust statistical effect sizes, this paper contributes the FORMS architecture and a replicable evaluation protocol, illustrating how high-fidelity conversational systems can reshape human information processing.

cs.HC↗

arXiv2026

GPUPHOT: A Python Framework for High-Performance GPU-Accelerated Photometry and Distributed Astronomical Data Reduction

We present GPUPHOT, an open-source Python framework for GPU-accelerated real-time photometry and astrometry of astronomical CCD and scientific CMOS images. Four of its seven stages run entirely on the GPU through CuPy (background estimation, source detection, PSF modeling and aperture photometry); the catalog crossmatch selects a CPU or GPU backend by problem size, and the zero-point and astrometric calibrations run on the CPU, within a containerized distributed system. Checkpoint-based GPU memory monitoring and an opt-in spatial-binning fallback let a single container image run on GPUs from a 4 GB laptop card to 80 GB datacenter accelerators. We benchmark the framework on nineteen observations from two robotic facilities, the Two-meter Twin Telescope and the Transient Survey Telescope, spanning 4.2 to 151.2 megapixels and 228 to 134,206 cataloged sources, on eight NVIDIA GPU platforms with one process per image. The H100 completes the densest 151.2-megapixel field end-to-end in 31.9 s, and GPU source detection on the A100 is 6-15x faster than the CPU library sep on the same frames. Once three sources of non-determinism are pinned, catalogs and zero points agree to the fourth decimal across GPU models and host CPUs. In this one-process-per-image regime the CuPy 14 / cuML stack showed a 7% lower peak memory and a median 38% higher per-image latency than CuPy 12, both due to the RAPIDS allocator displacing the CuPy memory pool at import; restoring the pool removes the memory difference and cuts the median overhead on datacenter GPUs to 11%, with identical output. Long-lived workers, the production mode, run the two stacks near parity. We recommend the CuPy 14 stack for its reproducibility and maintained libraries, not for memory or speed. GPUPHOT and its benchmark scripts are released for autonomous facilities that require end-to-end photometric reduction at survey cadence.

astro-ph.IM↗

arXiv2026

A High-Throughput AES-GCM Implementation on GPUs for Secure, Policy-Based Access to Massive Astronomical Catalogs

The era of large astronomical surveys generates massive image catalogs requiring efficient and secure access, particularly during pre-publication periods where data confidentiality and integrity are paramount. While Findable, Accessible, Interoperable, and Reusable (FAIR) principles guide the eventual public dissemination of data, traditional security methods for restricted phases often lack granularity or incur prohibitive performance penalties. To address this, we present a framework that integrates a flexible policy engine for fine-grained access control with a novel GPU-accelerated implementation of the AES-GCM authenticated encryption protocol. The novelty of this work lies in the adaptation and optimization of a parallel tree-reduction strategy to overcome the main performance bottleneck in authenticated encryption on GPUs: the inherently sequential Galois/Counter Mode (GCM) authentication hash (GHASH). We present both the algorithmic adaptation and its efficient execution on GPU architectures. Building on optimized GPU AES kernels from recent work in cryptographic acceleration, this work presents the first integration of these techniques into a high-throughput, FITS-aware encryption framework specifically designed for large-scale astronomical data, combining cryptographic authentication, dual-key access control, and direct compatibility with the standard astronomical Python ecosystem. Our implementation transforms the sequential GHASH computation into a highly parallelizable, logarithmic-time process, achieving authenticated encryption throughput suitable for petabyte-scale image analysis. Our solution provides a robust mechanism for data providers to enforce access policies, ensuring both confidentiality and integrity without hindering research workflows, thereby facilitating a secure and managed transition of data to public, FAIR archives.

astro-ph.IM↗

arXiv2022

Study and security analysis of the Spanish identity card

The National Identity Document is a fundamental piece of documentation for the identification of citizens throughout the world. That is precisely the case of the DNI (Documento Nacional de Identidad) of Spain. Its importance has been enhanced in recent years with the addition of a chip for the authentication of users within telematic administrative services. Thus, the document has since been called: electronic DNI or simply DNIe. Sensitive user information is stored in that integrated circuit, such as personal and biometric data, along with signature and authentication certificates. Some of the functionalities of the DNIe in its current version at the time of writing this work have been implemented for years in the DNI 3.0 version launched in 2015, and therefore have already been extensively studied. This work provides a theoretical and practical compilation study of some of the security mechanisms included in the current DNIe and in some of the applications that require its use. It has been carried out using only mobile devices and generic card readers, without having any type of privileged access to hardware, software or specific documentation for the interception of packets between the DNIe and the destination application. In other words, it is an exploratory analysis carried out with the intention of confirming with basic tools the level of robustness of this very important security token.

cs.CR↗

arXiv2022

Drowsiness detection in drivers with a smartwatch

The main objective of this work is to detect early if a driver shows symptoms of sleepiness that indicate that he/she is falling asleep and, in that case, generate an alert to wake him/her up. To solve this problem, an application has been designed that collects various parameters, through a smartwatch while driving. First, the application detects the driving action. Then, it collects information about the most significant physiological variables of a person while driving. On the other hand, given the high level of sensitivity of the data managed in the designed application, in this work special attention has been paid to the security of the implementation. The proposed solution improves road safety, reducing the number of accidents caused by drowsiness while driving.

cs.CR↗

arXiv2022

QuantumSolver: A quantum tool-set for developers

This paper introduces a new opensource quantum tool-set called QuantumSolver based on Qiskit to help developers without knowledge in quantum computing. The developed library includes a set of algorithms with different features: random number generation, Bernstein-Vazirani algorithm and quantum key distribution using the BB84 protocol. This paper described the main details about the implementation of the toolset, focusing in the challenges that the authors faced. Finally, this document analyzes the results obtained with some conclusions that authors compares with the included features.

cs.CR↗

arXiv2022

Using blockchain in the follow-up of emergency situations related to events

This paper describes a decentralized low-cost system designed to reinforce personal security in big events in case of emergency. The proposal consists of using smart contracts supported by blockchain in the management of events. An alternative communication channel that does not require any cloud service is also provided with the aim of improving the coordination of emergency services. Peers may use this emergency support tool to interact with each other through a chat when additional support is required. Since information security is mandatory in this scenario, Identity-Based Signcryption schemes are here used in order to guarantee communication confidentiality, authenticity and integrity. Depending on the communication mode (peer-to-peer or broadcast), different signcryption methods are used. A first implementation of the proposal has produced promising results.

cs.CR↗

arXiv2022

Secure system based on UAV and BLE for improving SAR missions

This work describes an integrated solution to face a civil security problem in the area of Search And Rescue (SAR) of missing people. This proposal is based on the use of emerging technologies such as Unmanned Aerial Vehicles (UAV), also known as drones, and the use of simulated beacons on smartphones. In particular, in the presented tool, drones fly synchronously in a specific area so that each drone uses on-board sensors to scan and detect any signal emitted by Bluetooth Low Energy (BLE) beacons from smartphones of missing people. This technique allows getting the GPS position of any detected missing person. This work also includes some security issues related to possible attacks focused on the perimeter and physical security.

cs.CR↗

arXiv2022

Priority and collision avoidance system for traffic lights

In this paper, a collision avoidance system is presented to detect red light running and warn nearby vehicles and pedestrians in real time in order to prevent possible accidents. No complex infrastructure-based solution such as those based on radars or cameras is here required. Instead, a new solution based on smartphones carried by drivers and pedestrians is proposed so that it is the device inside the vehicle violating a traffic light, the one that self-reports the offence in order to generate alerts and warn nearby vehicles and pedestrians to prevent accidents. The proposal could also be used by road authorities to collect data on traffic lights that are most frequently violated in order to define an action plan to investigate causes and look for solutions. It includes a classifier for learning and estimating driver behaviour based on collected data, which is used to predict whether he/she is about to run a red light or detect whether that has already happened. In the first case, the system broadcasts warnings directly to close vehicles and pedestrians through Wi-Fi, while in the second case, the proposal warns vehicles and pedestrians in the neighbourhood through a server. The solution also includes a prioritization system based on changing traffic lights at intersections according to the needs and characteristics of the traffic at all times, giving the top priority to emergency vehicles. Furthermore, the proposal involves the use of cryptographic schemes to protect authenticity and integrity of messages sent from traffic lights, smartphones and servers, and privacy and anonymity to promote the use of the system. A beta version with some parts of the proposal has been implemented and the obtained results are promising.

cs.CR↗

arXiv2022

Analysis and implementation of the SNOW 3G generator used in 4G/LTE systems

The fourth generation of cell phones, marketed as 4G/LTE (Long-Term Evolution) is being quickly adopted worldwide. Given the mobile and wireless nature of the involved communications, security is crucial. This paper includes both a theoretical study and a practical analysis of the SNOW 3G generator, included in such a standard for protecting confidentiality and integrity. From its implementation and performance evaluation in mobile devices, several conclusions about how to improve its efficiency are obtained.

cs.CR↗

arXiv2022

Using identity-based cryptography in mobile applications

This work includes a review of two cases study of mobile applications that use Identity-Based Cryptography (IBC) to protect communications. It also describes a proposal of a new mobile application that combines the use of IBC for Wi-Fi or Bluetooth communication between smartphones, with the promising Near Field Communication (NFC) technology for secure authentication. The proposed scheme involves NFC pairing to establish as public key a piece of information linked to the device, such as the phone number, so that this information is then used in an IBC scheme for peer-to-peer communication. This is a work in progress, so the implementation of a prototype based on smartphones is still being improved.

cs.CR↗

arXiv2022

Mutual authentication in self-organized VANETs

The practical deployment of vehicular networks is still a pending issue. In this paper we describe a new self-organized method of authentication for VANETs, which allows their widespread, fast and secure implementation. Our proposal does not involve any central certification authority because the nodes themselves certify the validity of public keys of the other nodes. On the one hand we propose an algorithm that each node must use to choose the public key certificates for its local store. On the other hand, we also describe a new node authentication method based on a cryptographic protocol including a zero-knowledge proof that each node must use to convince another node on the possession of certain secret without revealing anything about it, which allows non-encrypted communication during authentication. Thanks to the combination of the aforementioned tools, the cooperation among vehicles can be used for developing several practical applications of VANETs, such as detection and warning about abnormal traffic conditions. One of the most interesting aspects of our proposal is that it only requires existing devices such as smartphones, because the designed schemes are fully distributed and self-organized. In this work we include an analysis of both an NS-2 simulation and a real device implementation of the proposed algorithms, which enables us to extract promising conclusions and several possible improvements and open questions for further research.

cs.CR↗

arXiv2022

How to build vehicular ad-hoc networks on smartphones

Vehicular ad-hoc networks have been defined in the literature as communications networks that allow disseminating information among vehicles to help to reduce traffic accidents and congestions. The practical deployment of such networks has been delayed mainly due to economic and technical issues. This paper describes a new software application to detect traffic incidents and exchange information about them, using only smartphones, without any central authority or additional equipment. Both road safety and communication security have been taken into account in the application design. On the one hand, the interface has been designed to avoid distractions while driving because it operates automatically and independently of the driver, through voice prompts. On the other hand, communication security, which is essential in critical wireless networks, is provided through the protection of attributes such as authenticity, privacy, integrity and non-repudiation. All this is achieved without increasing the price of vehicles and without requiring the integration of new devices neither in vehicles nor on roads. The only prerequisite is to have a smartphone equipped with Wi-Fi connectivity and GPS location in each vehicle. The proposed application has been successfully validated both in large-scale NS-2 simulations and in small-scale real tests to detect traffic congestions and empty parking spaces.

cs.CR↗

arXiv2022

Software implementation of the SNOW 3G Generator on iOS and Android platforms

The standard for wireless communication of high-speed data in mobile phones and data terminals, called LTE (Long-Term Evolution) and marketed as 4G/LTE, is quickly being adopted worldwide. The security of this type of communication is a crucial factor mainly due to its mobile and wireless nature. This work includes a practical analysis of the SNOW 3G generator used to protect the confidentiality and integrity in LTE communications. In particular, several techniques to perform multiplications and LFSR operations have been studied and implemented on both iOS and Android platforms. The evaluation of those implementations led to some conclusions that could be used to improve the efficiency of future implementations of the standard.

cs.CR↗

arXiv2022

Improving Tourist Experience Through an IoT Application Based on FatBeacons

This paper describes the use of a new extension of the Bluetooth connection protocol, called FatBeacon, which faces the problem of obtaining information where no Internet connection is available. Rather than advertising a URL to load a web page, the FatBeacon protocol has the ability to broadcast any basic web contents actually hosted on the device. In particular, FatBeacons are here used to improve the tourist experience in places with no Internet coverage through a new application of the Internet of Things (IoT). Thanks to the fact that the web content is emitted by the own FatBeacon, any smartphone with Bluetooth Low Energy (BLE) can be used to receive touristic information, even in uncovered areas, such as rural or mountain destinations. This work does not only show the applicability of the new FatBeacon protocol, but it also presents a performance comparison of different BLE technologies used for similar touristic applications.

cs.CR↗

arXiv2022

Secure ambient intelligence prototype for airports

Nowadays, many technological advances applied to the Internet of Things (IoT) make the introduction of innovative sensors aimed to deploy efficient wireless sensor networks possible. In order to improve the environment and people's lives, real time analysis of certain environmental variables may favor the reduction of health risks related to the deterioration of air quality. To this respect, the proposed system implements a particular prototype of IoT device characterized by the assembly of ambient sensors capable of measuring pollutant gases, temperature and humidity. For this purpose, Raspberry Pi and Arduino platforms are used. Several security methods are introduced to ensure the integrity of air quality data by implementing Merkle Trees on each IoT node and on the Cloud server. Besides, the authenticity of IoT devices and the confidentiality of communications are guaranteed by implementing HTTPS requests. Finally, authentication tokens are used to identify system users, and different security rules are applied to manage database operations.

cs.CR↗

arXiv2022

Poster: Revocation in VANETs Based on k-ary Huffman Trees

One of the biggest problems of vehicular ad-hoc networks is revocation. The efficient management of such issue has become one of the major paradigms in this area of research. A solution proposed here is based on the use of authenticated data structures like revocation trees to replace the classical and inefficient certificate revocation lists. In particular, the idea of this paper is to propose the use of k-ary hash trees, Huffman coding and a duplex version of the SHA-3 hash function, to optimize insertions and searches in the revocation structure. Thus, the inclusion of a new certificate revoked in the tree, only implies a new iteration of the duplex construction of the hash function, avoiding recalculating the entire hashes and the entire tree. Furthermore, a k-ary Huffman tree is used to insert leaf nodes at different levels so that those revoked nodes that are more queried, are located closer to the root node position, so the revocation proof is smaller for those vehicles that spend more time on the roads. This paper details a method to calculate the optimum value $k$ for the k-ary tree in order to optimize the revocation proof size. Therefore, the proposal described here improves both the insertion of new revoked certificates in the revocation structure and the search of revoked certificates in the revocation structure. This paper is part of a work in progress, so that we plan to implement the scheme in real scenarios to get ideal values of the parameters and comparisons with other schemes.

cs.CR↗

arXiv2022

RFID authentication protocol based on a novel EPC Gen2 PRNG

Continuous advances of Information Technologies (ITs), and in particular of the RFID technologies that allow the connection between the physical world objects and the IT infrastructure, have guaranteed the improvement and efficiency of industrial technologies in the last decades. This paper includes the proposal of two new schemes for RFID. On the one hand, it describes the internals of a lightweight Pseudo-Random Number Generator (PRNG) suitable for low resource devices such as passive RFID complying with the EPC Gen2 specifications. On the other hand, a new secure mutual authentication protocol for such RFID devices that uses the proposed PRNG is presented. The design of the proposed PRNG is based on a nonlinear filter of a Linear Feedback Shift Register (LFSR), and the authentication protocol is lightweight. Both schemes fulfill all practical requirements of low-cost RFID such as resource limitation of EPC Gen2 tags. This is thanks to that only simple computation modules such as the proposed LFSR-based pseudorandom generator and bitwise operations are required. The combination of both proposals guarantees at the same time low power consumption and secure features such as authentication, confidentiality and anonymity.

cs.CR↗