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Cloud Enabled Body Area Network
Published in Sanjay Kumar Biswash, Sourav Kanti Addya, Cloud Network Management, 2020
Anupam Pattanayak, Subhasish Dhal
A hash function maps a input of variable length into a output of fixed length. Hash functions that are used in the security related applications are referred to as cryptographic hash functions [301]. Examples of cryptographic hash functions are MD-5, SHA-1, SHA-2, SHA-3, etc. A function needs to have three properties to qualify as cryptographic hash function. These three properties of hash functions are mentioned below: Preimage Resistance: Given a message digest y, it is computationally infeasible to find a message x that hashes to y.Second Preimage Resistance: Given a message x, it is computationally infeasible to find a different message x′, such that both the messages x and x′ hash to the same message digest.Collision Resistance: It is computationally infeasible to find two different messages that hash to the same message digest.
Advancing the Cybersecurity of Electronic Voting Machines Using Blockchain Technology
Published in Kuan-Ching Li, Xiaofeng Chen, Hai Jiang, Elisa Bertino, Essentials of Blockchain Technology, 2019
Nitin Sukhija, John-George Sample, Elizabeth Bautista
While there is no standard voting machine configuration, many share similar properties in the context of security. These machines use direct-recording, allowing the voter to interact with the machine by means of mouse, touch screen, etc. These votes are typically recorded and stored locally on the voting machine. In the case of WINVote systems used throughout the state of Virginia, votes were stored in a Microsoft Access database; storing all votes in a single, mutable point of failure made modifying votes trivial. By implementing a blockchain-based voting machine, the threat of compromising data locally is removed along with the benefit of hard encrypted data. The security features of blockchain are not exclusive for EVMs. A number of cryptographic hash functions are available, with one of the most common being SHA-256. Designed by the National Security Agency in 2001, SHA (Secure Hash Algorithm), the anonymous creator(s) of Bitcoin, Satoshi Nakamoto, implemented SHA-256 in the first blockchain where it is continued to be used for hashing. Moreover, the distributed ledgers inception was used in tandem with Bitcoin, a cryptocurrency. As the technology matures, its benefits in other areas are becoming more obvious. Many industries can benefit from the transparency that comes with utilizing blockchain. The combination of security and immutability facilitated by blockchain aids its applicability to voting machines, supply chains, and healthcare to name only a few.
Message Authentication
Published in Khaleel Ahmad, M. N. Doja, Nur Izura Udzir, Manu Pratap Singh, Emerging Security Algorithms and Techniques, 2019
One of the most complex areas of cryptography is authentication of message. Message authentication works in three different modules. The first module is about key generation; the second module is the algorithm, which takes the key and message as input and then produces MAC; and the third module requires an algorithm, which will be used for validation, i.e., a verifying algorithm, which verifies the MAC at receiver’s end. Cryptographic Hash Functions takes message as an input and produces a value that is called hash, which is used to validate message integrity. MAC and cryptographic hash functions have lot in common but they possess different security requirements. MAC at one end ensures authentication while hashing ensures integrity. But MAC and hashing could be combined to ensure both authentication and integrity.
Blockchain-based Light-weight Authentication Approach for a Multiple Wireless Sensor Network
Published in IETE Journal of Research, 2022
For developing the hash code, MBLAKEBC was used. For WSN, without the use of certificates, an authentication mechanism including a one-way and shared authentication is built via digital signatures. MBLAKEBC fulfils the one-way hash function protection requirements, for example, pre-image resistance, second pre-image resistance and collision resistance. Pre-image resistance, second pre-image resistance and collision resistance are the three key security characteristics provided by cryptographic hash functions. The collision resistance is maintained by MBLAKEBC and is responsive to the second pre-image threat. Taking ECDSA’s security into account, the threats on ECDSA primarily focus on the hash feature. The identity can be undermined if the hash function is indeed not collision and pre-image resistance. When it's not signature repudiation, collision resistance becomes feasible because if it's not collision resistant, the identity may be altered. Using just a variable length hash function is the approach. In contrast through the other cryptographic hash functions, MBLAKEBC would, therefore, be a better alternative. Result of a single point of failure, a node cannot behave as a CA in a system like WSN, so there could be a periodic modification in the CA, which is not an ideal choice, regarding security problems. Therefore, with low computational costs, this MBLAKEBC system offers certificate-less authentication.
Cryptanalysis and improvement of mutual authentication protocol for real-time data access in industrial wireless sensor networks
Published in International Journal of Computers and Applications, 2022
Devender Kumar, Sai Kishore Pachigolla, Shubham Singh Manhas, Karan Rawat
To prove the semantic security of the proposed scheme, we provide the definition of a collision resistant hash function and a secure PUF function . Collision-resistant one-way cryptographic hash function: It is a mathematical function which is deterministic in nature and it takes a string of variable length as an input and produces a string of fixed length, say n bits, as an output. More formally, for a hash function . Let denote the advantage of an attacker A in finding a hash collision for some hash H, then . For an -attacker A which is trying to attack the 's collision resistance, then with maximum runtime .Secure PUF function: For a secure PUF, if we have some arbitrary inputs , and some security parameters and , the maximum possible variation from the identical inputs is and the variation from non-identical outputs should be greater than or equal to . This means that if we have two PUF functions, say and , then , where represents hamming distance and p is threshold value for error tolerance.