Cryptography is considered to be different things depending on the peoples’ point of view. Children used to play ciphers and secret languages. This, however, it is not related to this cryptography. The cryptography or strong cryptography should provide a level of privacy, so you can prevent the critical information from decrypting by large organizations: mafia, big corporations and large states. This cryptography in the past was used only for military purposes. But now, with the emergence of the information-oriented society, it becomes a central tool to ensure confidentiality.
As the information society forms, the technological tehniques of total surveillance intended to control millions of people turn out available for the large states. Therefore, cryptography turned out one of the main instruments to ensure the confidentiality, trust, authentication, electronic payments, and plenty of other important things ("A Cryptography Tutorial and Introduction," n.d.).
Cryptography is not considered to be the notion of war, which is not worth getting involved. It is time to remove the veil of secrecy and to use all its capabilities for the benefit of modern society. Widespread cryptography is one of the few ways to protect the person from the situation when it is discovered a totalitarian state, which can monitor every person’s movement.
Imagine that you need to send a message to the recipient. And you worry about the protection of information before the recipient reads it. However, there is always a chance that someone will open an envelope or intercept an e-mail message.
In cryptographic terminology, the original message is called plain text (plaintext or clear text). The change of the source code intended to hide its content from others is called encryption (encryption). The encrypted message is named ciphertext. The process by which the ciphertext is extracted from the plaintext is named decryption. Usually in these processes it is used a key and the algorithm, therefore the message decryption can be fulfilled only on the assumption of knowing the key.
Cryptography is the science of how to ensure the privacy of the message. Cryptanalysis is aimed to open an encrypted message or how to extract the clear text if the key is not known. This science covers all the practical aspects of the private messaging, including authentication, electronic money and digital signatures. Cryptology is a branch of mathematics that studies the mathematical foundations of cryptographic methods.
Key Encryption Algorithms
The method of encryption / decryption is called a cipher. Some encryption algorithms base on the fact that he encryption method (algorithm) is secret. Now these methods are only of historical interest and have no practical significance. All contemporary algorithms thanks to a key control encryption and reverse one; message can be successfully decrypted only if the key is known. The key used to decrypt may not match the key used for encryption, but most algorithms keys coincide.
Research by Polk and Dodson (2006) illustrates that algorithms with the key application are divided into two classes: symmetric (or secret key algorithms) and asymmetry indices (or public key algorithms). The difference is that for the symmetric algorithms it is necessary to use the same key for encryption and decryption (or simply the decryption key calculated by the encryption key). While asymmetric algorithms use different keys, and the decryption key can not be calculated from the encryption key.
Symmetric algorithms include block ciphers and stream ciphers. Streaming allows you to encrypt information bitwise, while the block ones work with a certain set of data bits (usually the block size is 64 bits) and encrypt the set as a whole.
Asymmetric ciphers (public-key algorithm) foresee a public key being available to all (for example, published in the newspaper). This allows anyone to encrypt the message. However, only the right person can decrypt this message (the one who holds the key decryption). The key for encryption is called the public key, and the key for decryption - the private key or secret key.
Generally speaking, symmetric algorithms are faster than asymmetric. In practice, two types of algorithms are often used together: a public key algorithm is used to convey the secret randomly generated key, which is then used to decrypt the message.
Some asymmetric algorithms are significantly used to generate the digital signature. The digital signature is a block of data generated using a secret key. Thus, the public key can verify that the data was actually generated using this secret key. Algorithm for generating digital signatures should ensure that it was not possible without the private key to create a signature that will turn out correct during the checking procedure.
Digital signatures are regarded to verify that the message came from the sender really, assuming that only the sender has the private key corresponding to its public key. Also, signatures are used for stamping time (timestamp) on documents: the party to whom we trust, signs a document with a time stamp with the help of its secret key and thus confirms that the document had already existed at the time, announced in the time stamp.
According to Barker (2008), It is widely used by individuals and legal persons as an analogue of a handwritten signature for electronic document giving legal force equal legal force of the document, signed by the handwritten signature of the authorized person.
The use of electronic document management systems with DS significantly accelerates the numerous commercial operations, reducing the amount of paper accounting records, saving staff time and expanses of the company, related to contracts, registration of payment documents, reporting to regulatory authorities, obtaining the certificates from various government agencies.
Modern Methods of Cryptography Application
According to Oppliger (2005), The advent of affordable Internet transferred cryptography to a new level. Cryptographic methods have been widely used by individuals in the electronic business, telecommunications, and many other environments. Finally, it was established not state-controlled currency - Bitcoin.
Many enthusiasts quickly realized that bank transfer is a convenient thing, of course, however, for the purchase of such pleasant things in life, as a weapon, it is not suitable. It requires also authentication mandatory. Its transactions do not require an intermediary in the form of a bank or other financial institution, it is impossible to trace them. The network is completely decentralized, bitcoins cannot be frozen or seized, and they are fully protected against state control. At the same time bitcoin can be used to pay for any goods - with the consent of the seller.
The new electronic money are created by users, providing the computing power of their machines for the entire system BitCoin. This kind of activity is called mining. The dealing with mining alone is not very profitable, it is much easier to take advantage of special servers - pools. They combine the resources of several participants in a network, and then distribute the profits.
Quantum cryptography is intended to provide the level of protection of the information, and an unprecedented degree of reliability will be used in a conventional mobile communication device.
According to Horodecki (2010), The method of quantum cryptography is based on the principles of quantum mechanics, and the media are physical objects such as electrons or photons. A feature of this method of data encryption is its absolute reliability, guarantees the confidentiality of transmitted information.
Technologies are developed for several decades and has already been put into practice. Devices are equipped with quantum cryptography, such as server rooms for the Ministry of Defense and some of the larger banks. Being not cheap facility, it locates on the large area. It is clear that nowadays all this luxury of absolute privacy is not available for ordinary people.
Very soon we should expect the practical implementation of technology that will bring significant psychological relief to all of us - a huge army of Internet users and consumers of various online services range is constantly expanding. Owners of modern gadgets due to which they make purchases from online stores and use the services of Internet banking, will soon be able to do it with redoubled energy and enthusiasm, because the laws of quantum physics will provide them with a fantastic protection against any claims on their property.
Nowadays cryptography is the most important part of all information systems. It turns out a relevant tool beginning from e-mail to the cellular communication network and from the access to the Internet to e-cash. Cryptography provides accountability, transparency, accuracy and confidentiality. It prevents fraud attempts in e-commerce and provides the legal effect of financial transactions. Cryptography helps to establish your identity, but also provides you with anonymity. It prevents damage of the server and does not allow competitors to get access to your sensitive documents. And in the future, as commerce and communications are all closely connected with computer networks, cryptography becomes vital.
A Cryptography Tutorial and Introduction. Encryption, Decryption and Key Management. (n.d.). Retrieved April 2, 2015, from http://cryptographyworld.com/
Polk, W., & Dodson, D. (2006). Cryptographic algorithms and key sizes for Personal Identity Verification (Draft. ed.). Gaithersburg, MD: U.S. Dept. of Commerce, National Institute of Standards and Technology.
Barker, E. (2008). Recommendation for digital signature timeliness (Draft. ed.). Gaithersburg, Md.: U.S. Dept. of Commerce, National Institute of Standards and Technology.
Oppliger, R. (2005). Contemporary cryptography. Boston: Artech House.
Horodecki, R. (2010). Quantum cryptography and computing--theory and implementation. Amstderdam: IOS Press.