Quantum computing threatens to undermine classical cryptography by breaking widely deployed encryption and signature schemes. This paper examines enterprise readiness for quantum-safe cybersecurity through three perspectives: (i) the technologist view, assessing the maturity of post-quantum cryptography (PQC) and quantum key distribution (QKD); (ii) the enterprise (CISO/CIO) view, analyzing organizational awareness, risk management, and operational barriers; and (iii) the threat actor view, evaluating the evolving quantum threat and the urgency of migration. Using recent standards (e.g., NIST's 2024 PQC algorithms), industry surveys, and threat intelligence, we synthesize findings via a SWOT analysis to map strengths, weaknesses, opportunities, and threats. Results indicate uneven and generally insufficient preparedness: while PQC standards and niche QKD deployments signal technical progress, fewer than 5\% of enterprises have formal quantum-transition plans, and many underestimate "harvest now, decrypt later" risks. Financial, telecom, and government sectors have begun migration, but most industries remain exploratory or stalled by costs, complexity, and skills gaps. Expert consensus places cryptanalytically relevant quantum computers in the 2030s, yet delayed preparation could leave today's data vulnerable for decades. We recommend immediate steps: establishing crypto-agility, creating quantum transition roadmaps, prioritizing PQC deployment in high-value systems, and upskilling cybersecurity teams. A coordinated, proactive approach is essential to secure current and future digital assets in the quantum era.
Quantum computing threatens to undermine classical cryptography by breaking widely deployed encryption and signature schemes. This paper examines enterprise readiness for quantum-safe cybersecurity through three perspectives: (i) the technologist view, assessing the maturity of post-quantum cryptography (PQC) and quantum key distribution (QKD); (ii) the enterprise (CISO/CIO) view, analyzing organizational awareness, risk management, and operational barriers; and (iii) the threat actor view, evaluating the evolving quantum threat and the urgency of migration. Using recent standards (e.g., NIST's 2024 PQC algorithms), industry surveys, and threat intelligence, we synthesize findings via a SWOT analysis to map strengths, weaknesses, opportunities, and threats. Results indicate uneven and generally insufficient preparedness: while PQC standards and niche QKD deployments signal technical progress, fewer than 5% of enterprises have formal quantum-transition plans, and many underestimate "harvest now, decrypt later" risks. Financial, telecom, and government sectors have begun migration, but most industries remain exploratory or stalled by costs, complexity, and skills gaps. Expert consensus places cryptanalytically relevant quantum computers in the 2030s, yet delayed preparation could leave today's data vulnerable for decades. We recommend immediate steps: establishing crypto-agility, creating quantum transition roadmaps, prioritizing PQC deployment in high-value systems, and upskilling cybersecurity teams. A coordinated, proactive approach is essential to secure current and future digital assets in the quantum era.
The maturation of quantum computing hardware and algorithms has transformed what was once a theoretical concern into an active planning priority for governments, enterprises, and standards bodies. This paper assesses the current and projected threat that quantum computation poses to classical public-key cryptographic standards, namely RSA, elliptic curve cryptography (ECC), and Diffie-Hellman key exchange, all of which derive their security from mathematical problems that Shor's algorithm renders tractable on a sufficiently large fault-tolerant quantum computer. We synthesize recent hardware progress, algorithmic refinements that have substantially reduced estimated qubit requirements, and the finalization of NIST's post-quantum cryptography (PQC) standards (FIPS 203, 204, and 205) to provide an evidence-based assessment of where the field stands as of mid-2026. Particular attention is given to the widening gap between optimistic resource estimates, including a contested March 2026 claim of a thousand-fold reduction in factoring resources, and the practical reality that no existing quantum computer approaches the logical qubit counts required to threaten deployed encryption. We further examine migration challenges, including performance overhead, cryptographic agility, constraints on embedded and IoT systems, and the harvest-now-decrypt-later threat model that makes migration urgency independent of exact timeline predictions. Drawing on NIST transition guidance and recent G7 coordination targets, we argue that organizations should treat cryptographic migration as a present-tense operational requirement rather than a future contingency, regardless of unresolved disagreement among experts about when a cryptographically relevant quantum computer will exist. The paper concludes with practical recommendations for risk-based migration prioritization and identifies open research questions in cryptographic agility and quantum-resistant system design.
Quantum computing is no longer a distant concern for cybersecurity planning. Its progress has raised serious questions about the long-term reliability of widely used public-key cryptographic systems, especially RSA, elliptic curve cryptography, and related key exchange mechanisms that currently protect digital communication, cloud services, financial transactions, government systems, and enterprise information assets. The main concern is that powerful quantum algorithms could weaken the mathematical assumptions on which these systems depend, creating future risks for encrypted data, digital signatures, identity systems, and secure network protocols (Shor, 1994; Mosca, 2018). Post-quantum cryptography has therefore become a major cybersecurity readiness priority, not only as a technical replacement for vulnerable algorithms, but as a broader organizational migration challenge. Effective preparation requires cryptographic asset inventory, risk classification, crypto-agility, vendor coordination, interoperability testing, and phased deployment across complex information systems (Kumar, 2022; Campbell, 2025). This article examines the cybersecurity implications of quantum computing and reviews the major post-quantum cryptographic algorithm families, current standardization efforts, enterprise migration barriers, and strategic readiness measures needed for the quantum computing era. It also discusses the importance of aligning post-quantum migration with existing cybersecurity governance, information systems management, and long-term digital resilience planning. By emphasizing early preparation, structured migration, and continuous cryptographic governance, the article argues that organizations can reduce future quantum-related exposure and strengthen the security of critical digital infrastructure before large-scale quantum attacks become practical (NIST, 2024; NCCoE, 2025).
The arrival of cryptographically relevant quantum computers (CRQCs) represents an existential threat to the public-key cryptographic infrastructure underpinning global enterprise operations. Enterprise security today relies on RSA and elliptic-curve cryptography (ECC) for TLS, VPNs, PKI, code signing, and identity systems—all of which are fundamentally broken by Shor's algorithm on a sufficiently powerful quantum computer. The defining risk is time-shifted compromise: adversaries can harvest encrypted traffic today and decrypt it once CRQCs exist, a threat already underway according to U.S. intelligence assessments. NIST finalized three post-quantum cryptographic (PQC) standards in August 2024 (FIPS 203/204/205) and mandates deprecation of quantum-vulnerable algorithms by 2035. Yet only 5% of organizations have implemented quantum-safe encryption and 95% lack formal quantum transition plans. This paper provides a comprehensive, threat-driven analysis across seven dimensions: quantum algorithm impact, harvest-now-decrypt-later (HNDL) threat models, enterprise asset risks (PKI, TLS, VPNs, code signing, cloud, IoT, identity, blockchain, supply chain), sector-specific vulnerabilities (financial services, healthcare, critical infrastructure), cryptographic primitive analysis, migration standards and roadmaps, and enterprise readiness gaps. The convergence of HNDL attacks already underway, multi-decade data sensitivity windows, and 12–15 year enterprise migration timelines means the migration deadline has, for most sectors, already passed.
Abstract Classical computing architectures cannot reasonably solve computationally challenging problems, such as those of RSA public-key encryption, Diffie-Hellman key exchange, and elliptic curve cryptography, which form the cryptographic foundations of modern enterprise information security. Superposition and entanglement phenomena can be used to make quantum computers efficient in solving these problems, which are efficiently solved by Shor's algorithm and Grover's algorithm, and make existing cryptographic infrastructure entirely insecure. While quantum computing is fault-tolerant and still under development, the 'harvest now, decrypt later' threat model by which adversaries can harvest encrypted data now to be decrypted later when they can operate quantum systems signals that the cryptographic threat is present, not future. The objective of this study is to examine the current state of enterprise cryptographic readiness against threats in the quantum era and to create a model for organizational transition to the new cryptographic standards in the quantum era, which is called the Quantum-Resilient Security Architecture (QRSA) Framework. It uses a mixed-methods research methodology, consisting of a systematic literature review, an expert Delphi survey of 38 cybersecurity practitioners from 16 countries, and a qualitative analysis of five enterprise organizations, to examine the state of quantum-capable cryptographic protocols, the readiness of organizations in the technical, governance and capability aspects, and the most important enablers and blockers for the post-quantum migration. The key findings include that: 94 percent of enterprise systems assessed are today still using quantum-vulnerable cryptographic primitives; less than 12 percent of organizations surveyed have started formal planning efforts for quantum migration; and, in most of the cases analyzed, the National Institute of Standards and Technology (NIST) post-quantum cryptography standardization process has not made significant impacts on enterprise security roadmaps. The QRSA Framework offers a staged migration architecture based on the NIST standardized algorithms such as CRYSTALS-Kyber, CRYSTALS-Dilithium and SPHINCS+ that integrates with the enterprise security infrastructure. Contributions include cybersecurity governance scholarship, enterprise risk management theory, and information security policy.
Quantum computing poses an existential threat to classical public-key cryptography, particularly RSA and elliptic-curve systems, which form the backbone of secure communication, authentication, and digital trust. Once scalable quantum computers emerge, algorithms such as Shor’s will be capable of breaking these schemes, jeopardizing confidentiality and integrity across the internet and enterprise systems. Post-quantum cryptography (PQC) offers a viable defense, providing quantum-resistant algorithms that can be implemented on today’s hardware and protocols. Recent standardization milestones—including NIST’s approval of ML-KEM (Kyber) for key establishment, ML-DSA (Dilithium) and SLH-DSA (SPHINCS+) for signatures, and the selection of HQC as a complementary KEM—mark a turning point for practical adoption. This paper surveys the quantum threat model, algorithm families, performance trade-offs, and integration patterns such as hybrid modes and crypto-agile architectures. It further outlines a phased migration roadmap for enterprises, emphasizing harvest-now-decrypt-later risks and compliance imperatives. By bridging technical, operational, and policy perspectives, the study provides actionable guidance to prepare organizations for a secure and quantum-resilient future.
Quantum computing poses an existential threat to public-key cryptography, with Shor's algorithm capable of breaking RSA and elliptic curve systems once cryptographically relevant quantum computers (CRQCs) emerge. While post-quantum cryptography (PQC) offers algorithmic solutions, organizational readiness extends beyond technical implementation to encompass governance, interoperability, and adaptive capacity. This review synthesizes the quantum threat landscape, evaluates NIST-standardized PQC algorithms through quantitative performance analysis, and examines global standardization dynamics. We introduce a novel Quantum Readiness Maturity Model (QRMM) that enables organizations to assess and advance their preparedness across five dimensions: cryptographic infrastructure, governance frameworks, sectoral adaptation, interoperability resilience, and strategic agility. Applying this model to finance, telecommunications, and defense sectors reveals systematic gaps in migration planning and crypto-agility. Our analysis demonstrates that quantum readiness requires treating cryptographic transformation as a strategic enterprise capability rather than a purely technical upgrade. The proposed framework provides actionable pathways for practitioners while identifying critical research directions in hybrid deployment strategies, post-quantum PKI architectures, and algorithmic diversity.