Name: This would jeopardize the confidentiality presently enjoyed by



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Quantum and Post-Quantum Cryptography

Recent years have prompted research into
quantum computers. Quantum computers have been the subject of controversy due
to their abilities to solve complex mathematical phenomena that have been
primarily developed as the basis of information encryption .Given that these
large quantum computers are built, they shall inevitably compromise the key
cryptosystem that is currently in use. This would jeopardize the
confidentiality presently enjoyed by digital communication and internet users
worldwide. The primary objective of post-quantum cryptography is to create
cryptographic systems that can interoperate with existing communication
protocols. This paper shall look into common cryptographic topics and reflect
the effect of post cryptographic quantum computing on common information


Quantum key distribution


Quantum key distribution is indeed a
successful application to cryptography, quantum information that utilizes the quantum
mechanics theory to secure data ( Quantum key
distribution generates a random key between two points over an insecure
network. Quantum key distribution is founded on the following principles; the
superposition principle and the Heisenberg’s principle.  A one- time pad encryption scheme is created
and implemented using the securely distributed quantum key.  A great protocol of quantum key distribution is
the “BB84” protocol in which single qubits are chosen randomly from {???, ???, ???, ???} states and sent. QKD
provides that the key submitted is only used once. This eliminates chances of
prediction from the sender-receiver or the eavesdropper. Hence Quantum key
distribution guarantees reliable security over an insecure channel unlike in
post-quantum cryptography whose key algorithms’ security rely on hard
mathematical problems and the ability of a quantum computer, one that
preferably runs Shor’s algorithm, to solve them.



Symmetric cryptography & Symmetric key
management systems and protocols


involves the process of making messages non-readable by encoding them.
Cryptographic algorithms are grouped into symmetric and asymmetric encryptions.
The Symmetric encryption  makes use of
the same key during encryption and decryption processes.


A crucial problem in
symmetric key cryptography the key distribution. The key distribution must
happen secretly. However key sharing can happen in one some ways; a trusted
third party could get involved in sharing the key with the recipient.
Alternatively, the sender can physically deliver the key to the receiver. Equally,
if the communicators have previously used a key, they can communicate the new
key through encryption using the old key. This option is however risky since an
eavesdropper can gain access to the old key and equally get access to the  new key there hence. 


Hash functions

A cryptographic hash
function receives an input (message) computes it to produce a fixed-size alphanumeric
response. The response is referred to as a hash value or a digital fingerprint.
Hash functions are; easy to calculate for any given data. The alphanumeric text
provided from the hash function for any given message is impossible to compute
for those with a given hash. Another property that hash functions have is
uniqueness ( It is doubtful that
different messages shall have a common has to value. However with the
development of quantum computers, it is very likely that using the hash value,
the initial message could be computed and derived successfully. This would in a
high magnitude compromise the integrity of information passed over an insecure
channel. Other practical applications that use hash functions such as digital
signatures and authentication also face an integrity threat following the
development post-quantum cryptography.


Public key

Public key
cryptography (asymmetric encryption) utilizes two mathematical non-identical
keys. The two keys involved are a public and a public key. Each of these two
keys has different roles; the public key encrypts while the private key decrypts
( Private keys can
however not be computed from public keys. Public keys are therefore shared
hence allowing users a convenient content encryption platform. Given that the
public keys have to be shared, they are stored on digital certificates to
facilitate an efficient and secure sharing. Users, therefore, have them at
their disposal for encryption during information sharing. However, only the
users of private keys can decrypt the information.

Shor’s algorithm

algorithm was developed by a mathematician known as Peter Shor. His innovation
brought about a quantum algorithm for integer factorization.  All it takes is one post cryptography quantum
machine with enough qubits to solve quantum gates for 0((log N) 2(log log N) (log log log N)) without giving in to noise like contemporary computers (wini). For this reason, therefore, these quantum
computers can break public key cryptography which is based on Shor’s
algorithm.  The public key encryption is
pegged on a principle huge numbers are computationally impractical.  This thought is however only valid for
classical computers. The development of quantum computers withstanding,
software developers need to reach common ground with mechatronic engineers in
developing computing systems that shall not compromise the integrity of information
reliance and computing.



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