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Embracing Quantum Security: Defense in Depth Strategies for a Post-Quantum World

Discover defense-in-depth strategies for quantum security to protect against the emerging threats of quantum computing. Explore quantum security strategies and in-depth defense approaches for a post-quantum world. Safeguard your data against quantum computing threats.

Table of Contents

The Quantum Computing Revolution

A brief overview of quantum computing and how it's different from classical computing

Let's talk about quantum computing.

First introduced by famed physicist Richard Feynman in the 1980s, quantum computing leverages the principles of quantum mechanics to process information.

Instead of using classical bits (0's and 1's), quantum computers use "quantum bits," called qubits, which can represent both 0 and 1 simultaneously due to the phenomenon known as superposition.

Here is a simple analogy without going too deep:

Superposition is like a quarter spinning on a table. While the quarter is spinning, it's neither heads nor tails but a combination of both possibilities until it finally lands on one side. With quantum computing, the quarter can effectively be both heads and tails at the same time.

This concept allows quantum computers to perform multiple calculations in parallel, potentially solving problems exponentially faster than classical computers.

If you want to get a primer on physics and the concepts of quantum mechanics, check out Richard Feynman's book called Six Easy Pieces (while the concepts are still very advanced, Richard makes them easier to understand than any other resource I've ever read).

The Benefits of Quantum Computing

The benefits of quantum computing can include the following:

  • A seismic escalation of technology advancements across the board

  • Advancements in cryptography and Artificial Intelligence machine-learning capabilities

  • Improved search algorithms for large data sets - searching over a set of possible outcomes for complex pattern prediction and simulations

  • Factoring large numbers and performing complex scientific calculations

This revolutionary computing shift could lead to an exponential threat landscape shift for the world.

Economic Impact of Quantum Computing

The potential economic impact of quantum computing is staggering, with projections suggesting it could unlock billions or even trillions in value across various sectors. Enhancements and optimizations in material and life sciences, chemicals, pharmaceutical research, the automotive industry, and more could help humankind make gigantic leaps forward.

A study by McKinsey & Company from April 2023 highlighted that quantum computing could generate an annual value of $620 billion to $1.3 trillion .

The potential for these advancements alone underscores the critical need for quantum security measures to protect economic interests and maintain competitive advantages.

Potential Concerns about Advancements in Quantum Computing

With quantum computing will come unknown levels of computational power. It's not hard to imagine the misuse of that level of power by bad actors, and some concerns are:

  • Breaking current technology and security protections across the world

  • Potential national security concerns with military and economic imbalances

  • Advances of Nation State attack capabilities

  • Limiting other country's abilities to access new technologies and developmentally stunting nations

  • Increased mass surveillance and spying

This revolutionary computing shift could lead to an exponential threat landscape shift for the world.

Quantum Security: Building a Multi-Layered Defense

The Rising Importance of Quantum Security

Quantum security is an emerging field of cybersecurity and one that is just starting to be understood. Quantum security focuses on providing protection and encryption for data and communications once quantum computing is more broadly available.

The current applications of quantum security are all about making other things “quantum-resistant.



Pronunciation: KWON-tuhm ree-ZIS-tuhnt


Technologies built to safeguard digital data against the computational capabilities of emerging quantum computers.

Some of those methods include:

  • Post-Quantum Cryptography (PQC) - implementing new cryptographic algorithms based on new mathematical problems, structures, and implementations to be quantum-resistant.

  • Quantum Key Distribution (QKD) - using quantum computing to generate new encryption keys that cannot be replicated or broken due to the nature of quantum entanglement, making it quantum resistant.

  • Quantum Random Number Generation (QRNG) - a method for generating truly random numbers using the unpredictable nature and laws of quantum mechanics instead of deterministic methods used by traditional computing, making it quantum-resistant.

What is Potentially at Risk with Quantum Computing?

Quantum computers have the potential to break several encryption standards due to their ability to solve complex mathematical problems much faster than classical computers. This includes:

  • Email, chat, and SMS messaging

  • Browser encryption

  • Mobile app connections

  • Encrypted passwords and hashes

  • Any SSL/TLS encryption and public key cryptography using RSA and Elliptic Curve Cryptography (ECC)

Simply put, encryption algorithms are based on math, and quantum computers will be the world's best mathematicians.

So what can we do about it?

Prepping Your Business for Quantum Computing

Practical Steps Toward Quantum Readiness

While still largely theoretical in many aspects, once it does become "real," it may be too late. Defense-in-depth still remains true. There is a strong change your executive team is already hearing scary stories about the "disastrous effects that quantum computing will bring, so it's a good idea to start having these conversations in your companies.

How should you think about applying defense-in-depth practices to quantum security? Here are a few things you can do to get yourself prepared as a cybersecurity organization:

  • Educate stakeholders - Raise awareness among decision-makers about the importance of quantum security and the need for investment in quantum-resistant solutions.

  • Focus on a data protection strategy - discover and manage all keys, leverage various methods of de-valuing data (tokenization), and have an accurate inventory of your data

  • Evaluate your scope - inventory the cryptographic risks across your organization and 3rd parties (i.e., find out where there are weaker key lengths or algorithms used)

  • Scale up your standards - update internal encryption standards, increase key sizes for symmetric and asymmetric keys, remove weak ciphers from your scope

  • Data retention - ensure policies and procedures are in place to destroy confidential data once records are no longer required

  • Collaborate with experts: Engage with industry leaders and researchers in quantum computing and security to facilitate the development and implementation of cutting-edge solutions.

Quantum Threats Mapped to STRIDE

Threat model out what the risks might be. If you're not familiar with Threat Modeling, it can be best described as:

A structured representation of all the information that affects the security of an application. In essence, it is a view of the application and its environment through the lens of security

STRIDE is a popular threat modeling framework, and here I'll share a non-exhaustive list of quantum computing threats mapped to this framework.

STRIDE evaluates the system detail design. It models the in-place system. By building data-flow diagrams (DFDs), STRIDE is used to identify system entities, events, and the boundaries of the system.

Here are a few examples using STRIDE to threat model for quantum computing applications:

Spoofing - Pretending to be something or someone you’re not[S1] Forging Digital Signatures
[S2] Impersonating Legitimate Entities
Tampering - Modifying something you’re not supposed to modify[T1] Modifying Encrypted Data
[T2] Unauthorized System Configuration Changes
Repudiation - Claiming you didn’t do something regardless of whether you did or not[R1] Denying Actions
[R2] Forging Cryptographic Proofs
Information Disclosure - Exposing information to people who are not authorized to see it[I1] Decrypting Sensitive Data
[I2] Breaking Secure Communications
Denial of Service - Attacks designed to prevent a system from providing service[D1] Compromising Encrypted Systems
[D2] Rendering Encrypted Data Inaccessible
Elevation of Privilege - A program or user with access to do things that they are not supposed to do[E1] Breaking Encryption and Authentication
[E2] Unauthorized System Access

This is just a place where you can start to think through the ramifications and come up with an approach. It’s better to have some planning instead of no planning on these kinds of things.

Key Players and Innovators in Quantum Security

Who is Working on Quantum Security?

Various organizations and initiatives are developing quantum-resistant encryption methods and securing digital assets against quantum threats:

  1. National Institute of Standards and Technology (NIST): is working on the Post-Quantum Cryptography Standardization project to identify and standardize quantum-resistant cryptographic algorithms.

  2. European Telecommunications Standards Institute (ETSI): a Quantum Safe Cryptography (QSC) working group dedicated to researching and developing quantum-resistant cryptographic standards.

  3. PQCRYPTO Project: an EU-funded initiative to develop and analyze post-quantum cryptographic algorithms.

  4. Open Quantum Safe (OQS): an open-source project that aims to provide quantum-safe cryptographic solutions, including libraries and tools for developers to implement and test quantum-resistant encryption.

  5. Microsoft Quantum Development Kit (QDK): resources for learning and experimenting with quantum-resistant cryptographic algorithms and tools for developing quantum applications.

  6. IBM Quantum Experience: a cloud-based quantum computing platform with resources for learning about quantum cryptography and experimenting with quantum algorithms.

  7. Google Quantum AI: resources and tools for learning about quantum computing and quantum cryptography, as well as experimenting with quantum algorithms.

Staying informed about these developments and engaging with the resources provided by these organizations will help in preparing for the quantum era.

Other References

Wrapping Up

I hope you've enjoyed this point of view on quantum security challenges and learned something new. This is an extremely technical concept, so I did not go very deep into much of the terminology because it is very academic at this point. The references I mentioned above will let you dig deeper into any of these topics.

This post isn't intended to be an exhaustive list of threats and best practices but a general point of view and orientation to help prep yourself and your company. This space is going to change so fast, so please let me know if I missed something.


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