Md Tariqul Islam ‘Pavel’
Assistant Professor of Cybersecurity
Department of Information Systems
UMBC
12 noon–1pm
Friday, October 3, 2025
Remotely via WebEx: https://umbc.webex.com/meet/sherman
Abstract:
Distributed ledger technologies (DLTs) continue to face significant security challenges. While attackers constantly adapt
their strategies, governance mechanisms often remain static. Our work addresses this critical gap by introducing a
framework for self-defending ledgers, where nodes enforce ledger security through adaptive governance driven by multi-
agent reinforcement learning (MARL) grounded in game-theoretic principles. We model DLT consensus as a repeated
Bayesian game, in which participants hold probabilistic beliefs about peer behavior, allowing agents to make strategic
decisions under partial observability of adversarial actions. Our framework enables nodes to model, detect, and respond to
a wide range of malicious behaviors, including bribery, selfish mining, equivocation, Sybil attacks, and collusive voting,
by continuously updating Bayesian trust beliefs and governance policies based on network observations. We formally
prove that networks with an honest majority reach stable equilibria and provide bounds on adversarial influence.
Experiments across five major protocols show that agents effectively identify attacks with high accuracy while
substantially reducing adversarial success. This work demonstrates the potential of game-theoretic MARL to provide
robust, self-adaptive security in varied DLT environments, paving the way for resilient and autonomous ledger
governance.
About the Speaker:
Md Tariqul Islam ‘Pavel’ is an assistant professor of cybersecurity in the Department of Information Systems at UMBC.
His research centers on the security, efficiency, and fault-tolerance of distributed computing systems, with a strong
emphasis on blockchain, cloud, and vehicular networks. He develops formal models, algorithms, and protocols that
address critical vulnerabilities in decentralized ecosystems, spanning inter-blockchain communication, smart contract
migration, and trustworthy governance. His work combines cryptography, game theory, and system design to build
scalable, resilient infrastructures. He earned his PhD and MS from the University of Kentucky and BS from the University
of Dhaka, Bangladesh. Email: mtislam@umbc.edu, URL: https://paveltariq.com/
Host:
Alan T. Sherman, sherman@umbc.edu
Support for this event was provided in part by the National Science Foundation under SFS grant DGE-1753681.
The UMBC Cyber Defense Lab meets biweekly Fridays 12-1pm. All meetings are open to the public.
Upcoming CDL meetings:
Oct 17, 2025: Mohammad Mohammadisiahroudi (Math)
Oct 31, 2025: Alan Sherman, String Matching by Humans through Simultaneous Presentation
Nov 14, 2025: Fabio Anza (Physics)
Nov 28, 2025: Thanksgiving weekend
Dec 12, 2025: Alan Sherman and Enis Golazewski, Security Analysis of the SecureDNA System