- Trending Categories
- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies

- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who

# What is Quantum Cryptography and how is it better than Classical Cryptography

## Origin of Cryptography

All great civilizations have strived to send communications in a secure manner. Only the Mesopotamians, ancient Greeks, ancient Chinese, and Spartans utilized encryption to keep their transmissions secret. Though these civilizations utilized advanced cryptography at the time, they were not impenetrable. Throughout the years, cryptography has progressed to a point where our brains are unable to decipher it on their own anymore.

As of now, quantum cryptography is the most sophisticated kind of encryption that exists. Although Stephen Wiesner initially proposed it in the 1970s, it was first published in 1983. It's no secret that quantum cryptography is a hot study area right now, thanks to quantum computer advancements. These quantum computing advancements pose a danger to the most extensively used key distribution methods in use today, according to a recent report. A quantum computer can potentially solve a mathematical problem that can't be solved by existing computers in polynomial time but is theoretically possible on a classical computer. In fact, quantum cryptography does not rely on computing security but rather on quantum physics rules. This insight sparked the study into quantum cryptography

## Classical Cryptography

Cryptography handles hidden knowledge by taking a plaintext communication and turning it into an incomprehensible message to anybody who might be interested in it. Due to the increasing number of people who use the Internet for a variety of purposes, including e-commerce and online banking, the demand for cryptography is expanding dramatically. Security services such as secrecy, authenticity, and accountability should be addressed via cryptography.

To prevent unauthorized disclosure of information, the communication must be kept confidential. *Authenticity* and *accountability* are used to verify that the sender is who he or she claims to be. By combining a plaintext message with a key, and generating a ciphertext, these aims can be achieved. Anyone without the key to deciphering the message will be unable to use this encrypted text.

There are certain mathematical tasks, such as factoring two big primes, that are NP-hard. Due to the difficulty of computing the function in one direction, these issues are known as

**trapdoor functions**.Traditionally, cryptography has been divided into

**asymmetric**and**symmetric cryptography**. It’s a type of cryptography that employs a single secret key for encryption and decryption.Both the public and private keys can be used for encryption and decryption in Asymmetric cryptography (also known as public-key cryptography).

It relies on the NP-hardness of mathematical problems and does not provide theoretical security, but rather computational security

As a result, a mathematical breakthrough may possibly invalidate public-key cryptography, rendering symmetric keys insecure when sent through asymmetric cryptography.

When you consider that the vast majority of e-commerce and authentication services now in use employ asymmetric encryption, it's no wonder that this is an issue.

## Quantum Cryptography

As opposed to depending on an untested mathematical issue, quantum cryptography ensures the security of data transmission by using principles of physics that we understand to be true.

First suggested in the 1970s, it wasn't until the early 1990s that it was applied to the field of information security.

Aside from solving the key distribution problem, quantum cryptography does not really convey any meaningful information.

Regardless of whether the photons of light are transmitted either through fiber optics or through empty space, they conform to the Heisenberg uncertainty principle or quantum entanglement.

Uncertainty is created when a photon's characteristics are encoded with information, such that any attempt to monitor the photon will change those properties and be observable, according to Heisenberg.

According to the quantum theory, some physical qualities are complementary, thus measuring one changes the other.

*Quantum entanglement*is a condition in which two or more photons are physically entangled, notwithstanding their spatial separation. Measurements made on one system will appear to have an instantaneous effect on the other systems that are tightly linked, even if they are physically distant.