Protect critical infrastructure without exhausting computing, memory, and energy resources Cybersecurity techniques require enormous computing, memory, bandwidth, and energy resources, creating tension between resource-availability for protection and sustainability. Sustainability of Cybersecurity introduces sustainable cybersecurity—ensuring security without exhausting available resources. Edited by scientists from VTT Technical Research Centre of Finland and University of Oulu, this seven-part volume examines communication networks, software, hardware, privacy, regulations, and emerging technologies. This resource covers sustainable cybersecurity in the quantum era, 6G networks, distributed ledger and blockchain technologies, and AI applications. It uniquely addresses technological sustained performance, resilience, and adaptability perspectives alongside political dimensions including regulations and public policy. Real-world case studies demonstrate how critical infrastructures from public healthcare to transportation systems are sustainably secured in digitally connected environments. Readers will also discover: Analysis of sustainability in cybersecurity from perspectives of longevity, resilience against resource exhaustion, and persistence of connected infrastructures and architectures.Investigation of political aspects including global regulatory landscapes and public policy perspectives affecting cybersecurity implementation and governance decisionsCoverage of emerging security challenges and solutions alongside quantum cryptography, 6G networks security frameworks, and distributed ledger and blockchain technologies.Case studies demonstrating sustainable secure digitization of critical infrastructures spanning healthcare systems, industrial networks, and defense.Examination of AI and machine learning applications for intelligent security solutions, threat modeling, and adaptive security architectures.Designed for researchers in academic institutions, technology industries, and government organizations, this book provides the depth required for advancing sustainable security practices. Professors, researchers, scientists, and regulatory bodies will find authoritative guidance on balancing cybersecurity effectiveness with resource conservation across emerging technology domains.