Introduction to Public-Key Cryptography

Security approaches in Wireless Sensor Networks (WSNs) are normally based on symmetric cryptography. Instead of symmetric encryption, some alternative approaches have been developed by using public-key cryptography. However, the higher computational cost represents a hard limitation to their use. In this paper, a new key management protocol is proposed. A transitory symmetric key is used to authenticate nodes in the network during the key establishment. However, pairwise keys are established using asymmetric cryptography. A theoretical analysis shows that the computational effort required by the public key cryptosystem is greatly reduced, while the security of the network is increased with respect to state-of-the-art schemes based on a transitory master key. Moreover, an experimental analysis demonstrates that this proposed approach can reduce the time spent for key establishment by about 35%.

These days information systems that use asymmetric cryptography or public key cryptography are widely spread all over the world. The reason of this fact is a rather high reliability of existing algorithms. In terms of information security, we can distinguish the following important tasks: ensuring the availability of information, its authenticity and confidentiality. All these problems can be solved with the help of electronic digital signature (hereinafter-EDS). It ensures the integrity of information, its confidentiality, authenticity and the origin. EDS is widely used in various commercial and governmental organizations that are obliged to follow the state standard GOST R 34.10-2012 Information technology. Cryptographic protection of information. The processes of forming and checking electronic digital signature. In the view of the above we perform a comparative analysis of the state standard GOST R 34.10-2012 with the state standards GOST R 34.10-2001 and R 34.10-1994 to find their relevance, reliability and complexity. Due to the fact that EDS is based on a special hash function, the authors of this article have also reviewed the state standards GOST R 34.11-2012 and GOST R 34.11-1994. To estimate hash function generation time, the Python Code which uses the Pygost Library has been written. Furthermore, hacking complexity assessments of the algorithms themselves have been realized. Therefore, estimations of speed and performance procedures generation and signature verification have been made and the hacking complexity assessments of the Russian state standards are realized. The approximate durations of forced entry are calculated and the advantage of the new state standard GOST R 34.10-2012 is justified. As a result of the analysis the relevance, the reliability and the complexity of the state standard GOST R 34.10-2012 have been turned out. In spite of all the strength benefits the new standard requires more time effort for hash-function formation and for the digital signature formation.

Cryptography plays a crucial role in securing information and communications in the face of advancing technologies. Asymmetric encryption, also known as public-key cryptography, plays a crucial role in cryptography. Unlike symmetric encryption, which uses a single key for both encryption and decryption, asymmetric encryption involves a pair of keys, namely a public key and a private key. Asymmetric cryptography is closely associated with the secure management of keys, addresses, and transactions within the blockchain ecosystem, especially in cryptocurrency platform. In this study,we present a novel concept known as rainbow vertex antimagic coloring. This concept extends the idea of rainbow vertex coloring by incorporating antimagic labeling. Let f : E(G) → {1, 2, . . . , |E(G)|} be a function, where the weight of a vertex v ∈ V (G) with respect to f is defined as wf (v) = Σe∈E(v) f(e). Here, E(v) denotes the set of edges incident to v. Thefunction f is termed a vertex antimagic edge labeling if it assigns distinct weights to each vertex. A path is termed a rainbow path if, for any vertices u and v, all internal vertices on the u − v path have distinct weights. The rainbow vertexantimagic connection number of a graph G, denoted by rvac(G), is defined as the minimum number of colors requiredin any rainbow coloring derived from rainbow vertex antimagic labelings of G. In this paper, we will obtain some newlemmas or theorems concerning rvac(G), and we will implement the obtained lemmas or theorems of RVAC on asymmetric cryptography technique.

Nowadays security is main issue during transmission of data. Among many cryptographic methods, ECC is the public key asymmetric cryptosystem which provides faster computation over smaller size in comparison to other asymmetric key cryptosystems. In this paper, we have proposed a group security algorithm using the ECC cryptography algorithm. The group security is applied to ECC in terms of m-gram selection called ECC m-gram selection. Due to the group security implementation in terms of common grams, processing speed will be faster in comparison to individual item security. We have also made the comparison study between the traditional ECC algorithm with the proposed group security algorithm using generalized frequent-common gram selection for depicting lesser time requirements to achieve better security for the whole process.

We propose a non-cascaded and crosstalk-free multi-image encryption method based on optical scanning holography and 2D orthogonal compressive sensing. This approach enables the simultaneous recording and encryption of multiple plaintext images without mechanical scanning, while allows for independent retrieval of each image with exceptional quality and no crosstalk. Two features would bring about more substantial security and privacy. The one is that, by employing a sequence of pre-designed structural patterns as encryption keys at the pupil, multiple samplings can be achieved and ultimately the holographic cyphertext can be obtained. These patterns are generated using a measurement matrix processed with the generalized orthogonal one. As a result, one can accomplish the differentiation of images prior to the recording and thus neither need to pretreat the pending images nor to suppress the out-of-focus noise in the decrypted image. The other one is that, the non-cascaded architecture ensures that different plaintexts do not share sub-keys. Meanwhile, compared to 1D orthogonal compressive sensing, the 2D counterpart makes the proposed method to synchronously deal with multiple images of more complexity, while acquire significantly high-quality decrypted images and far greater encryption capacity. Further, the regularities of conversion between 1D and 2D orthogonal compressive sensing are identified, which may be instructive when to manufacture a practical multi-image cryptosystem or a single-pixel imaging equipment. A more general method or concept named synthesis pupil encoding is advanced. It may provide an effective way to combine multiple encryption methods together into a non-cascaded one. Our method possesses nonlinearity and it is also promising in multi-image asymmetric or public key cryptosystem as well as multi-user multiplexing.

Optical image encryption algorithm based on hyper-chaos and public-key cryptography

One Time Password (OTP) provides an additional layer of authentication to a web server, protecting against fraudulent attempts so that the information is protected between the user and the recipient. In the field of Steganography, various techniques are employed to conceal data in the media in such a manner that human perception cannot identify it. As the proposed algorithm is a combination of both Cryptography and Steganography it meets all the challenges very efficiently. Initially, the data is ciphered with a novel algorithm of asymmetric key cryptography and then the ciphered message is camouflaged in the cover media using the Least Significant Bit (LSB) steganography technique. Even if the intruder cracks the LSB algorithm used here, he will get the encrypted data since the source data is not present on the cover media. To obtain the original data, the ciphered data must be deciphered with the deciphering algorithm. With the additional security, it is impossible to crack the original data from the cover media

In the papers [New features for public key exchange algorithms, in: 18-th International ICWG Meeting (Krakow 2011)], [Strongly asymmetric PKD cryptographic algorithms: An implementation using the matrix model, in: Proceedings ISEC Conference (Shizuoka 2011)] a new scheme to produce public key agreement (PKA) algorithms was proposed and some examples based on polynomials (toy models) were discussed. In the present paper we introduce a non-commutative realization of the above mentioned scheme and prove that non-commutativity can be an essential ingredient of security in the sense that, in the class of algorithms constructed, under some commutativity assumptions on the matrices involved, we can find a breaking strategy, but dropping these assumptions we can not, even if we assume, as we do in all the attacks discussed in the present paper, that discrete logarithms have zero cost.

This article resolves the problem of logical representation of the classical asymmetric RSA public key encryption algorithms (Rivest, Shamir, and Adleman) and El Gamal in order to implement them on hard devices (microcontrollers). It is shown that the algorithms under study can be described by a set of micro-instructions consisting of a sequence of operators and, based on the analysis of graph-schemes, logical, algebraic and matrix representations of algorithms, construct a minimal logical representation for implementation on hard devices

The exponential development in Quantum Computing is becoming a threat to the existing asymmetric cryptographic algorithms like RSA (Rivest, Shamir, Adleman). A threat to these public key cryptographic algorithms is a threat to the entire Internet itself, as algorithms like RSA are the basic building blocks of existing secure Internet communication. Thus, a new area of quantum cryptography emerged, that lead to the development of Post-Quantum Cryptography (PQC) algorithms and Quantum-safe Internet protocol Quantum Key Distribution (QKD). These systems, which are generally known as Quantum Cryptographic Systems, have many practical limitations that make them complex and expensive to be implemented or even experimented with, in a real-life scenario. Therefore, to develop new protocols and analyze the feasibility of the existing protocols in a cost-effective manner, we need efficient simulation frameworks. So, in this paper, we are profiling some of the recent Quantum Cryptographic based networks and Quantum Key Distribution (QKD) simulation frameworks and conducting a systematic and thorough analysis of the implementation and functionalities of these experimental platforms, with an aim to build a universal quantum testbed in the future.

In order to improve the security in the process of audio files in Internet communication, first Construct a generating chaotic sequence of six dimensional cellular neural network model, according to the principle of RSA asymmetric encryption algorithm, proposes a location of any number as a transmission key(Coordinate key) in the chaotic sequence and using the public key and RSA encryption algorithm for it. Then the number corresponding to this key position, as the starting point of Chebyev chaotic mapping, and to generate encryption sequence. Finally encrypt the original audio and send to receiver with the transport key. In order to verify the practicability of the algorithm, we made a simulation experiment, the complexity of the test the transmission key and comparison of the original audio and the encryption audio waveform figure, and proves the feasibility of this kind of encryption algorithm through the correlation analysis, spectrum analysis and sensitivity analysis. There is the broad prospect and the important application of chaotic and RSA encryption technology.

New communications paradigms such as wireless communications for handheld devices have increased requirements for operating speed of relevant security mechanisms, such as encryption for confidentiality, hashing for message integrity and combined hashing and public key encryption for digital signature. Existing secure services have traditionally been implemented by employing hybrid cryptographic protocols, i.e. combinations of symmetric and asymmetric (public key) algorithms to handle both effective key management and cryptographic performance. These solutions are in increasing degree becoming obsolete by the trend to connect end users with terminals with limited storage and processing power via wireless networks, sometimes established in a totally ad hoc fashion, with little or no centralized management to organize user authorization for access to secured services. New, lightweight protocols are in increasing demand, and the cryptographic primitives necessary for implementation of such protocols also need to be adapted to these new user scenarios.At NTNU/Q2S, research in this area has been ongoing for a period of time resulting in a number of new solutions adapted to the new paradigm encompassing mobile users of distributed communication services. In this talk, some of the general features of the new cryptographic primitives will be described. The designs are mainly based on new insight into the characteristics of quasigroups and quasi group string operations.

Objectives: Public key cryptography helps in achieving information security in wireless networks. Public key will be issued by CA (Certificate Authority). But having CA in wireless network makes it vulnerable to various attacks. Hence distributed cache was proposed where each node in network caches public key of some nodes existing in network in its cache and request to obtain keys not cached will be made via trusted nodes. Due to limited memory only few keys can be cached. There exists an optimal threshold value for caching keys so that equal number of both local nodes and remote nodes public keys can be cached. Methods: Random replacement policy was used for updating cache contents, where if a node’s local/ remote key cached ratio exceeds optimal ratio then a key will be randomly chosen from the cache and will be removed. Here we propose implementation of bloom filter in cache to cache public key of nodes existing in network. Findings: By using bloom filter of large size, more number of public keys can be cached thereby providing space and time advantage and reduces query cost with increased usage of memory. MAC (Media Access Control) id and PSN (Processor Serial Number) are used for uniquely identifying each node in network and are stored in encrypted format. When mismatch is found in encrypted MAC id and PSN, then that node is determined to be malicious node and its id will be notified to all nodes in network thus excluding the node from making any communication to other nodes in the network. Applications: Used for checking an element’s presence in the set thus reducing I/O lookup when large data set is used. Used as an alternative to cache as it uses limited memory more efficiently than cache does.

Notice of Violation of IEEE Publication Principles<br><br>"Modified Integer Factorization Algorithm using V-Factor Method"<br> by Prashant Sharma, Amit Kumar Gupta and Ashish Vijay<br> in the Proceedings of the Second International Conference on Advanced Computing and Communication Technology, January 2012, pp. 423-425<br><br> After careful and considered review of the content and authorship of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE's Publication Principles.<br><br> This paper is a duplication of the original text from the paper cited below. The original text was copied without attribution (including appropriate references to the original author(s) and/or paper title) and without permission.<br><br> Due to the nature of this violation, reasonable effort should be made to remove all past references to this paper, and future references should be made to the following article:<br><br> "VFactor: A Simple Algorithm for Integer Factorization"<br> by Vikas Pareek and Manisha Sharma<br> in the Proceedings of the International Conference on Computer Engineering and Technology (ICCET), November 2010<br><br> <br/> RSA is the asymmetric cryptography system. The security of RSA public key cryptosystem is based on the assumption that factoring of a large number (modulus). Integer Factorization is an important problem mainly due to its connection with RSA algorihm of Public key cryptography. We present a new special purpose algorithm (VFactor) for factoring. We compare this algorithm with Fermat's Factorization algorithm (FFM) and trial division algorithm (TDM) and we show that VFactor's runtime depends on the difference of factors and is independent of size of the modulus. So it's effective whenever factors are close to each other. In that case VFactor outperforms FFM and TDM. Keywords: Integer factorization, RSA algorithm, Fermat's Method of Factorization, Public key cryptography, TDM.

Authentication of public keys in asymmetric cryptography is an important objective to fulfil. Identity-based schemes are an efficient solution for this scenario. There are various identity-based schemes that are based on either factoring problem or DLP problem, but these problems can be solved in polynomial time using quantum computers. Multivariate cryptography is one of the main alternatives for the construction of post-quantum digital signature schemes. Digital signature construction needs modest computations in multivariate public key cryptography, so these schemes are considered quite efficient. In this paper, we present a new identity-based signature scheme in which the signature size and user key size are relatively small. The design of our proposed signature scheme is based on MQDSS construction.KeywordsMultivariate public key cryptographyMQ problemIdentity-based signature scheme