September 2025
Understanding Quantum Cryptography:
A Guide for IT Administrators
In today’s fast-changing digital landscape, quantum cryptography is becoming one of the most important topics for IT and network security professionals. As an IT administrator, you already manage encryption, firewalls, and authentication protocols every day. Quantum computing introduces new challenges and opportunities that could transform how we protect data in the coming decade.
This article explains the fundamentals of quantum computing, why it threatens existing encryption, and what steps you can take now to prepare.
Quantum vs. Traditional Computers
Traditional computers process information using bits, which represent either a 0 or a 1. They perform operations sequentially, solving problems step by step. This method has powered decades of innovation, from email servers to cloud storage.
Quantum computers, by contrast, rely on qubits, which can exist in multiple states simultaneously. This property allows them to perform many calculations at once. Tasks that might take classical computers years could take a quantum machine minutes or seconds.
Quantum computers are not replacements for traditional hardware. They are highly specialized tools that can solve certain problems more efficiently. However, today’s quantum systems remain in the early stages of development. Current models have limited qubits, high error rates, and require extremely controlled environments. Companies like IBM and Google are leading the field, but widespread use is still several years away.
Why Quantum Computers Pose a Threat
Modern encryption relies on mathematical problems that are difficult for classical computers to solve. Systems such as RSA and ECC depend on operations like factoring large prime numbers or solving discrete logarithms. The difficulty of these problems makes public-key encryption and digital signatures secure under current conditions.
Quantum computing changes that assumption. In 1994, mathematician Peter Shor introduced an algorithm capable of factoring large numbers exponentially faster than classical computers. On a sufficiently powerful quantum computer, this could make today’s encryption obsolete.
An attacker could use a quantum computer to derive private keys from public ones, effectively breaking HTTPS, VPNs, and most digital certificates. Even symmetric ciphers like AES, though more resilient, would face increased exposure due to Grover’s algorithm, which speeds up brute-force attacks.
For IT teams, this threat is not just theoretical. Once scalable quantum computers emerge, encrypted communications, stored data, and digital signatures could all be compromised.
“Harvest Now, Decrypt Later”
One of the most concerning tactics is the harvest now, decrypt later approach. Adversaries, including nation-states and advanced criminal groups, are already intercepting encrypted data and storing it for the future.
At present, this data cannot be decrypted by classical systems. However, when large-scale quantum computers become available—potentially within the next decade—those archives could be unlocked.
Imagine encrypted emails, contracts, or medical records sent securely in 2025 being decrypted in 2035. The implications for privacy, national security, and compliance are enormous.
This is why it is critical to start assessing which of your data assets have long-term sensitivity. Review your encryption standards and retention policies to ensure that sensitive information will remain protected long after it is transmitted.
What Is Post-Quantum Cryptography?
Post-Quantum Cryptography (PQC) refers to new encryption algorithms designed to resist attacks from quantum computers while running on existing hardware. These include lattice-based, hash-based, and code-based schemes that rely on mathematical problems quantum machines cannot efficiently solve.
Unlike quantum key distribution (QKD), which requires specialized equipment, PQC algorithms integrate directly into existing systems. They can be deployed in servers, browsers, and network appliances without new physical infrastructure.
In 2025, PQC reached a major milestone when NIST finalized its post-quantum standards. The newly approved algorithms include ML-KEM, ML-DSA, and SLH-DSA. These standards mark the beginning of a global transition toward quantum-resistant encryption.
Government agencies and major technology providers such as Microsoft and Google are already working to incorporate PQC into their products and frameworks.
PQC and TLS 1.3
One of the first areas of adoption is TLS 1.3, the latest version of the protocol that secures most web traffic. TLS 1.3 emphasizes forward secrecy and performance efficiency. To achieve post-quantum security, it introduces hybrid key exchanges that combine classical algorithms (like X25519) with PQC algorithms (like ML-KEM).
This hybrid model ensures that even if one algorithm is broken, the connection remains secure. The Internet Engineering Task Force (IETF) has standardized these methods, and support is already appearing in platforms such as OpenSSL, Chrome, and Firefox.
Older versions of TLS cannot accommodate these hybrid exchanges, making migration to TLS 1.3 a necessary step for any organization preparing for the post-quantum era.
How Network Box Is Preparing Clients
At Network Box USA, our latest NBRS-8 firmware includes full support for post-quantum cryptography. Administrators can enable hybrid TLS configurations and deploy quantum-resistant algorithms for critical connections.
These upgrades allow organizations to begin transitioning safely without disrupting existing workflows. PQC readiness does not mean rushing into new technology blindly; it requires balancing forward progress with compatibility for legacy systems such as HTTPS web servers and SMTPS mail.
By adopting PQC today, IT administrators position their organizations to remain secure, compliant, and future-ready.
Key Takeaways for IT Administrators
Begin evaluating your data’s long-term confidentiality needs.
Plan your migration to TLS 1.3 and consider hybrid key exchange options.
Review your encryption configurations and certificate management practices.
Stay informed about NIST and IETF PQC standards and updates.
Deploy technologies, such as NBRS-8, that support post-quantum readiness.
Quantum computing may not be mainstream yet, but the transition to quantum-safe security is already underway. By acting now, IT professionals can ensure that the data they protect today will remain safe in the world of tomorrow.
