## Question:

Write an essay about on a research topic which is Cryptography and quantum computing. The essay to be written is not a summary of the lecture notes or other course material given, or any other material available on the Internet. The essay has to go "beyond what was been covered in class". The essay should demonstrate ? A good understanding in detail of a specific topic chosen in Computing Theory. ? A holistic understanding of the areas in Computing Theory relevant to the essay topic and how they relate. For e.g. look at the suggested ’topic of interest’ given above. The maximum length of the above essay or paper should not exceed 6 pages though the ideal would be about 5 pages. This does not mean that you need to write this much. You may write as much is needed to clearly demonstrate your understanding at the same time being precise and comprehensive. Keep it simple and neat with a lucid flow. Typing could be using Times New Roman font size 12 or Arial font size 11 with 1.5line spacing. Marking rubrics for the essay is attached. Evaluation The evaluation is based on a good report, a good discussion of the findings in a clear, concise and presentable format. You may lose marks if the topic for the essay is too broad and reflects that not enough time has been spent for research.

## Answer:

### Introduction

This essay provides information on the topic “Cryptography and Quantum Computing”. The cryptography is a technique for securing the data by sending the data in the encrypted form so that it is decoded only by the valid and authorized user. It helps in securing the e-mail message, information of credit card, as well as for securing the corporate data. The data is converted into the unreadable form i.e. it is converted into the encrypted form, and send it to the receiver, and it read only by the users that have a key to unlock the data so that data is accessed only by the authorized user. It helps in protecting the data from the hackers or any unauthorized person. This process is mandatory, but it is not the sufficient process for securing the data. The quantum computing, it is based on the qubits. It is stored in the form of 1, 0 or both 0 and one simultaneously. It is also called the superposition of two different states. There are different started in the quantum computing and the states consist of n power of 2 form. The pair of qubits consists of four different states. It helps in solving the complex problems efficiently.

### Cryptography and Quantum Computing

Cryptography: It is a process of protecting the data and sending it in the encrypted form. The message is sent in the encrypted form from one point to another point. It helps in maintaining the integrity of the information (Kim, 2016). The process of encrypted the data into the unreadable form is known as cipher text. The encrypted message is broken by the help of cryptanalysis i.e. also known as code breaking. This process is helpful in securing the e-mail, information of credit card, as well as for securing the corporate data. The data is converted into the unreadable form i.e. it is converted into the encrypted from and send it to the receiver, and it read only by the users that have a key to unlock the data so that data is accessed only by the authorized user. It helps in protecting the data from the hackers or any unauthorized person. This process is mandatory, but it is not the sufficient process for securing the data. It is divided into two parts: private key encryption, and public key encryption.

In private key encryption, the private key or the same key is used by the sender as well as by the receiver. The sender sends the encrypted message (the algorithm is used for encrypted the message) to the receiver and the receiver decrypt the message by using the same private key as used by the sender of the message. The private key encryption is also known as symmetric cryptography.

In public key encryption, this system is based on two keys. The public key is available for all i.e. everyone is familiar with this key, but the private key is only known to the receiver of the message. The message can be sent to any user in the encrypted form, but it is only received by the authorized user i.e. the only user that has a private key can unlock this message. It contains two different keys (Kumar, 2015). The one key is used for the encryption process, and this is used for the decryption process. It allows only one person to read the message (who has a private key to decode the message). It is also a useful source for the digital signatures. The public key encryption process is also known as asymmetric cryptography.

Quantum computing: The quantum term plus computing term yields the quantum computing. (Minkel, 2016). There are various complex issues that are not tacked by the powerful computer. In a case of classical computing, the data is stored in the memory in the form of bits o or 1 (i.e. the information is stored in the digital form). But in a case of quantum computing, it is based on the qubits. It is stored in the form of 1, 0 or both 0 and one simultaneously. This is also called the superposition of two different states. There are different started in the quantum computing, and the states consist of n power of 2 form. The pair of qubits consists of four different states. It helps in solving the complex problems efficiently and in a fast manner. These problems which are solved using quantum computers are known as BQP. (BQP- Bounded Error, probabilistic, polynomial time). If the user wants a computer that looks a smaller in size, but it yields more powerful results, then the quantum computing is the solution to this problem. No doubt the quantum computing process is more complex as compare to the normal computing process, but it provides the results at millions of times better and faster than normal computing systems. In a case of conventional computers, they are slow as compare to the quantum computers because in a case of conventional computers the problem is solved by the help of mathematical operations (i.e. by adding or by subtracting the bits). The complex problems are solved by applying a series of simple operations on the problem (even the multiplication process is performed by the series of adding operations). The quantum computers work in a parallel mode whereas the traditional computers work in a serial mode. The computing process in case of quantum computing is more complex as compare to the traditional computing process.

### The quantum computers are related to the term cryptography

The quantum computing is a big threat for the private key algorithm as well as for the public key algorithm. The quantum computing helps in solving complex problems, and it also performs complex operations that can’t be performed by the conventional system. But on the other hand, it causes a big threat for the private communication. The quantum computer can easily break the cryptography keys and this further initiates the eavesdropper to enter into the private communication, and it steals the identity of someone and pretends to be that person, and in this way, it can damage the useful information. There are various security controls that can be broken by the quantum attack (attack by the quantum computer): The security protocols that are derived from the public-key ciphers. The second is any product which is derived from the above security protocol.

The post-quantum cryptography is developed for the cryptographic algorithm that is used for securing the attacks that are occurred from the quantum computers.

## Conclusion

The quantum computing provides the results at millions of times better and faster than normal computing systems. The quantum computing helps in solving complex problems, and it also performs complex operations that can’t be performed by the conventional system. It helps in solving the complex problems efficiently and in a fast manner (Kim, 2016).These problems which are solved using quantum computers are known as BQP. (BQP- Bounded Error, probabilistic, polynomial time). If the user wants a computer that looks a smaller in size, but it yields more powerful results, then the quantum computing is the solution to this problem. The conventional computers, they are slow as compare to the quantum computers because in case of conventional computers the problem is solved by the help of mathematical operations (i.e. by adding or by subtracting the bits). The complex problems are solved by applying a series of simple operations on the problem (Kumar, 2015). But on the other hand, it is a big threat to the symmetric cryptography as well as for the asymmetric cryptography. It causes a big threat for the private communication. The quantum computer can easily break the cryptography keys and this further initiates the eavesdropper to enter into the private communication and it steals the identity of someone and pretend to be that person, and in this way it can damage the useful information.

## References

Blencowe, M. (2011). Quantum computing: Quantum RAM. Nature, 468(7320), pp.44-45.

Ergun, A. (2014). Skewness and Kurtosis Persistence: Conventional vs. Robust Measures. SSRN Electronic Journal.

Ferr?ndez, J. and Mira, J. (2016). Non-conventional computing paradigms. Natural Computing, 8(4), pp.643-644.

Freund, R. (2014). DNA Computing Based on Splicing: The Existence of Universal Computers. Theory of Computing Systems, 32(1), pp.69-112.

Kim, K. (2016). Cryptography: A New Open Access Journal. Cryptography, 1(1), p.1.

Kristanto, S. (2015). Organizational Commitment Differences: Islamic vs. Conventional Banks. SSRN Electronic Journal.

Kumar, A. (2015). Asymmetric Key Cryptography. SSRN Electronic Journal.

Minkel, J. (2016). Quantum leap for quantum computing. IEEE Spectr., 43(3), pp.17-18.

Miszczak, J. (2012). High-level Structures for Quantum Computing. Synthesis Lectures on Quantum Computing, 4(1), pp.1-129.

Seife, C. (2015). What Are the Limits of Conventional Computing?. Science, 309(5731), pp.96-96.

Wiedermann, J. and Petr??, L. (2011). On the Universal Computing Power of Amorphous Computing Systems. Theory of Computing Systems, 45(4), pp.995-1010.

Yamamoto, Y., Takata, K. and Utsunomiya, S. (2012). Quantum Computing vs. Coherent Computing. New Generation Computing, 30(4), pp.327-356.