How to Encrypt Personal Data in the Age of Quantum Computing

Quantum Computing Era: Redefining Encryption Strategies for Personal Data Protection

As of May 27, 2026, the world is navigating a new security paradigm amidst the rapid advancements in information and communication technology. In particular, the emergence of quantum computing poses a fundamental threat to existing digital information security systems, highlighting the urgent need for countermeasures to ensure the secure preservation of personal data. Consequently, the transition to 'Post-Quantum Cryptography (PQC)' is evolving from a mere technical challenge into an essential strategy for protecting personal privacy and the value of data assets. What preparations should individuals make for the coming age of quantum computing?

The Advent of Quantum Computing and the Vulnerabilities of Current Encryption Systems

Quantum Computing: A Driver of Innovation and a Potential Security Catastrophe

Quantum computing leverages quantum mechanical principles such as superposition and entanglement to solve complex calculations in a fraction of the time it would take conventional computers, potentially taking billions of years. This capability is expected to drive innovation across a wide range of fields, including drug discovery, materials science, and financial modeling. However, this immense computational power paradoxically presents a critical threat capable of rendering widely used public-key cryptosystems, such as RSA or Elliptic Curve Cryptography (ECC), obsolete. Shor's algorithm, developed in 1994, mathematically proved that quantum computers can efficiently solve the integer factorization and discrete logarithm problems, which are the foundations of these public-key cryptosystems. This implies that current security infrastructure could become highly vulnerable in the face of quantum computers.

The Shift to Post-Quantum Cryptography (PQC): The Core of Future Security

Despite the uncertainty surrounding the practical implementation timeline of quantum computers, the threat of 'Collect Now, Decrypt Later'—where data collected today could be decrypted by quantum computers in the future—is already materializing. Sensitive personal identification information, financial transaction records, medical histories, and business secrets, if collected and stored long-term, are at risk of being reinterpreted in the quantum computing era. To preemptively address these security threats, the development and standardization of 'Post-Quantum Cryptography (PQC)', a next-generation cryptographic technology based on new mathematical challenges difficult for quantum computers to solve, are accelerating globally. This will become a key pillar of future data security.

Current Status of Post-Quantum Cryptography (PQC) Technology and Standardization Trends

PQC Algorithms Armed with Diverse Mathematical Principles

Post-Quantum Cryptography (PQC) refers to new algorithms that are secure against attacks from quantum computers. These algorithms are broadly based on diverse mathematical principles, including lattice-based, code-based, multivariate polynomial, hash-based, and the recently gaining attention isogeny-based approaches. Standardization efforts for PQC algorithms are actively underway, primarily led by the U.S. National Institute of Standards and Technology (NIST). Some algorithms have already been selected as candidates for standardization and are undergoing evaluation and review for actual system implementation. Each type of PQC algorithm has unique characteristics in terms of encryption/decryption speed, key size, computational load, and security strength, making the selection of an algorithm optimized for specific applications or usage environments increasingly important.

NIST Standardization Progress and Global Industry Response

The NIST PQC standardization process serves as a significant indicator leading global technological trends. NIST announced its first set of standard algorithm candidates in July 2022, and the final standardization work for the third generation of algorithms is currently in its concluding stages. This process aims to establish key algorithms as standards around 2024, which will provide a decisive impetus for companies to develop concrete roadmaps for PQC adoption. Numerous leading IT companies and security specialists are already accelerating their research and development of PQC algorithms and are rushing to integrate PQC technology into their products and services. These movements reflect the proactive willingness of the industry to prepare for the quantum computing era.

Clearly Identifying and Prioritizing Personal Data Assets

The first step to securing personal data in the age of quantum computing is to clearly recognize and catalog the personal data assets one possesses. It is essential to systematically organize what types of data (personal identification information, financial information, medical records, work documents, photos, videos, etc.) are held, where they are stored (personal PCs, smartphones, cloud storage, external storage devices, etc.), and in what quantities. Crucially, the process of classifying data by priority is essential, especially for data that requires long-term retention or is highly sensitive. This classification allows for clear criteria to determine which data should receive priority for post-quantum encryption. For example, it is reasonable to seek PQC solutions immediately for personal financial records that need to be stored for over ten years.

Reviewing Current Encryption Methods and Exploring PQC Transition Plans

It is crucial to meticulously examine the current encryption methods applied in the software, applications, operating systems, and services you use. If you are using outdated encryption methods or public-key algorithms vulnerable to quantum computers, you should actively consider transitioning to alternatives that support PQC. For software developers, integrating PQC libraries into their development environments is important, while for general users, choosing security software, cloud services, or VPNs that support PQC is vital. These are practical measures to ensure quantum resistance across all stages of data processing, including storage, transmission, and communication. For instance, when selecting file encryption software, it is advisable to check for PQC support.

Long-Term Data Storage and a Guide to Choosing Personal Tools

The threat of quantum computing will not materialize suddenly at a specific point in time but will gradually unfold. Therefore, for important personal data requiring long-term storage, an 'Encrypt-then-Migrate' strategy can be considered. This involves encrypting the data with PQC algorithms at the current time and planning to migrate the data according to the final PQC standards once they are fully established. Individual users should gradually strengthen the quantum resistance of their personal data by actively utilizing tools that currently support or plan to support PQC technology, such as encryption software (file/disk encryption), secure messengers, and end-to-end encrypted email services. For example, after the NIST standardization announcement in 2024, consider switching to secure messengers that support the finalized standards.