39.0HEMay 21
Self-Supervised ConvLSTM for Fermi Large Area Telescope Transient DetectionAlberto Garinei, Stefano Speziali, Alessandro Vispa et al.
We present a framework for detecting transient gamma-ray phenomena in a controlled environment by combining end-to-end simulations of the Fermi-LAT sky with self-supervised spatio-temporal deep learning. We generate a ten-year synthetic Universe with gtobssim and process the simulated events into daily all-sky maps of counts and exposure, obtaining a time-ordered sequence that mirrors the structure of Fermi-LAT observations. To model the nominal evolution of the sky, we employ a Convolutional Long Short-Term Memory (ConvLSTM) network that operates directly on map sequences, preserving spatial locality while learning temporal dependencies. The model is trained to reconstruct expected emission, and departures from the learned baseline are quantified through pixel-wise mean-squared residual maps. We then define statistically motivated anomaly criteria by estimating per-pixel thresholds from the residual distribution on the training set, and we enforce spatial coherence via local filtering to suppress isolated fluctuations. The ConvLSTM is then deployed as trained predictor on Fermi-LAT daily maps, where the sky can depart from the nominal behavior because of genuine astrophysical variability and instrumental non-stationarities. The resulting pipeline flags localized, time-dependent excesses consistent with high-variable sources or transient events (e.g., flares or GRBs) and provides a benchmark for evaluating anomaly-detection strategies on long-duration, Fermi-LAT-like datasets.
CRMar 24, 2021
TRADE: TRusted Anonymous Data Exchange: Threat Sharing Using Blockchain TechnologyYair Allouche, Nachiket Tapas, Francesco Longo et al.
Cyber attacks are becoming more frequent and sophisticated, introducing significant challenges for organizations to protect their systems and data from threat actors. Today, threat actors are highly motivated, persistent, and well-founded and operate in a coordinated manner to commit a diversity of attacks using various sophisticated tactics, techniques, and procedures. Given the risks these threats present, it has become clear that organizations need to collaborate and share cyber threat information (CTI) and use it to improve their security posture. In this paper, we present TRADE -- TRusted Anonymous Data Exchange -- a collaborative, distributed, trusted, and anonymized CTI sharing platform based on blockchain technology. TRADE uses a blockchain-based access control framework designed to provide essential features and requirements to incentivize and encourage organizations to share threat intelligence information. In TRADE, organizations can fully control their data by defining sharing policies enforced by smart contracts used to control and manage CTI sharing in the network. TRADE allows organizations to preserve their anonymity while keeping organizations fully accountable for their action in the network. Finally, TRADE can be easily integrated within existing threat intelligence exchange protocols - such as trusted automated exchange of intelligence information (TAXII) and OpenDXL, thereby allowing a fast and smooth technology adaptation.