Quantum Cryptography Communication: The Future of Absolutely Secure Developed by Next-Generation Communication Infrastructure

In modern society, digital data communication is like blood. From economic activities to personal privacy to national security, we always rely on the confidentiality of communication. However, conventional public key encryption methods are at risk of being deciphered by the dramatic improvement of computer technology and the appearance of quantum computers.

Quantum cryptography, which is based on the laws of physics itself as the foundation of security, is attracting attention. In this article, we will explain in depth the mechanism of this innovative technology, its impact on society, and the current state of implementation.

Table of Contents

1. Why is the current encryption "broken"?

The Core of Quantum Cryptographic Communication: Quantum Key Distribution (QKD)

3. Challenges for Social Implementation of Quantum Cryptography

4. How will the future society change?

Conclusion: To survive the Quantum Age

1. Why is the current encryption "broken"?

Currently, public key cryptography such as RSA encryption widely used on the Internet relies on the difficulty of factoring a huge number. However, this is based on computational complexity security that it takes a huge amount of time to calculate on the current computer, and it is not protected by mathematical proof.

"Quantum computers" that will appear in the future will boast overwhelming speeds that are incomparable to conventional computers in specific calculations. Especially if a method called "Shore's algorithm" is used, the current mainstream public key encryption may be decrypted in a short time. This is called "Quantum Computer Threat (Q-Day)."

The Core of Quantum Cryptographic Communication: Quantum Key Distribution (QKD)

Quantum Key Distribution (QKD) is the most promising solution to this threat. QKD is a technology that uses the basic properties of quantum mechanics to share a key that is absolutely detected by eavesdropping between two parties communicating.

Eavesdropping Detection Using Quantum Properties

The core of quantum cryptography is the property that "quantum changes its state when observed."

Alteration by uncertainty principle and observation: The state of a quantum (such as a photon) is determined the moment a third party tries to snoop (observe), and the original state is destroyed.

Eavesdropping detection: The communicating party checks for abnormalities (increased error rate) in the communication path during the process of generating the key. If there is an eavesdropper, the quantum state will always be disturbed, so the generation of the encryption key can be immediately stopped to ensure security.

Why can we say "absolute safety"?

While conventional encryption is broken when the performance of the computer improves, quantum encryption guarantees information theoretical security that decryption is impossible unless the laws of nature (physics) are broken. This is why quantum encryption is called the ultimate encryption.

3. Challenges for Social Implementation of Quantum Cryptography

In theory, it is a perfect quantum cryptography, but there are some high barriers to practical application.

Limit of Distance

Quantum signals are attenuated when passing through fiber cables. In conventional optical communication, signals can be strengthened by optical amplifiers, but simple amplifiers cannot be used because quantum states are broken by observation. To overcome this limitation, the development of quantum repeaters and research on quantum communication via space using satellites are being promoted.

Integration with existing infrastructure

Quantum cryptography, which requires expensive dedicated equipment, does not replace all communication. It is expected to be introduced sequentially in areas where extremely high confidentiality is required, such as important state secrets, financial data, medical information, etc.

4. How will the future society change?

In a society where quantum cryptography communication has become widespread, the following changes are expected to occur.

True privacy protection: Zero decryption concerns in banking transactions and e-government services.

Long-term information security: You can protect future data from the risk that future quantum computers will analyze data obtained today (so-called steal now and decrypt later attacks).

Rebuilding trust: Physically proving communications themselves will dramatically increase trust in the digital economy.

Conclusion: To survive the Quantum Age

Quantum cryptography is not just an update to encryption technology. It is an attempt by humans to control the physical laws of nature and fundamentally rewrite the concept of communication security.

In Japan, NICT (National Institute of Information and Communications Technology) is conducting world-class quantum cryptography research. As of 2026, the evolution of quantum computers and defense measures for quantum cryptography are playing cat and mouse. However, what awaits the competition is a truly secure communication infrastructure that will not be shaken no matter how high-performance machines appear.

In order for us to continue our activities in the digital sea with peace of mind, it is now necessary to correctly understand the new "shield" of quantum encrypted communication and accept it as a society.

Do you want to know more about the technical details of quantum cryptography communication and how far communication is currently successful?

# DeepTech Quantum technology The Quantum Internet # security # DX