Topic
Null cipher
About: Null cipher is a research topic. Over the lifetime, 146 publications have been published within this topic receiving 2480 citations.
Papers published on a yearly basis
Papers
3 Jan 1992
TL;DR: Two modifications of this cipher are discussed that may lead to practical provably-secure ciphers based on either of two assumptions that appear to be novel in cryptography, viz., the (sole) assumption that the enemy's memory capacity (but not his computing power) is restricted and the assumption that an explicit function is, in a specified sense, controllably-difficult to compute, but not necessarily one-way.
Abstract: Shannon's pessimistic theorem, which states that a cipher can be perfect only when the entropy of the secret key is at least as great as that of the plaintext, is relativized by the demonstration of a randomized cipher in which the secret key is short but the plaintext can be very long. This cipher is shown to be “perfect with high probability.” More precisely, the eavesdropper is unable to obtain any information about the plaintext when a certain security event occurs, and the probability of this event is shown to be arbitrarily close to one unless the eavesdropper performs an infeasible computation. This cipher exploits the assumed existence of a publicly-accessible string of random bits whose length is much greater than that of all the plaintext to be encrypted; this is a feature that our cipher has in common with the previously considered “book ciphers”. Two modifications of this cipher are discussed that may lead to practical provably-secure ciphers based on either of two assumptions that appear to be novel in cryptography, viz., the (sole) assumption that the enemy's memory capacity (but not his computing power) is restricted and the assumption that an explicit function is, in a specified sense, controllably-difficult to compute, but not necessarily one-way.
342 citations
20 Aug 2013
TL;DR: This paper considers the case where the adversary neither chooses nor knows the input messages, and has only access to the faulty cipher texts, and is able to describe several attacks against AES-128 by using non uniform fault models.
Abstract: Classical Fault Attacks often require the ability to encrypt twice the same plaintext, in order to get one or several pairs of correct and faulty cipher texts corresponding to the same message. This observation led some designers to think that a randomized mode of operation may be sufficient to protect block cipher encryption against this kind of threat. In this paper, we consider the case where the adversary neither chooses nor knows the input messages, and has only access to the faulty cipher texts. In this context, we are able to describe several attacks against AES-128 by using non uniform fault models. Our attacks target the last 4 rounds and allow to recover the correct key with practical time complexity, using a limited number of faulty cipher texts. This work highlights the need for dedicated fault attack countermeasures in secure embedded systems.
192 citations
10 Dec 2000
TL;DR: A5/1 is the stream cipher used in most European countries in order to ensure privacy of conversations on GSM mobile phones and is the best known result with respect to the total work complexity.
Abstract: A5/1 is the stream cipher used in most European countries in order to ensure privacy of conversations on GSM mobile phones. In this paper we describe an attack on this cipher with total work complexity 239.91 of A5/1 clockings, given 220.8 known plaintext. This is the best known result with respect to the total work complexity.
181 citations
TL;DR: A symmetric key image cryptosystem based on the piecewise linear map that can fight against the chosen/known plaintext attacks due to the using of plaintext-related scrambling and has many merits such as high encryption/decryption speed, large key space, strong key sensitivity, strong plaintext sensitivity, good statistical properties of cipher images, and large cipher-text information entropy.
Abstract: A symmetric key image cryptosystem based on the piecewise linear map is presented in this paper. In this cryptosystem, the encryption process and the decryption process are exactly same. They both include the same operations of plaintext-related scrambling once, diffusion twice and matrix rotating of 180 degrees four times. The length of secret key in the system is 64d where d is a positive integer. The proposed system can fight against the chosen/known plaintext attacks due to the using of plaintext-related scrambling. The simulate results and comparison analysis show that the proposed system has many merits such as high encryption/decryption speed, large key space, strong key sensitivity, strong plaintext sensitivity, strong cipher-text sensitivity, good statistical properties of cipher images, and large cipher-text information entropy. So the proposed system can be applied to actual communications.
122 citations
TL;DR: This paper models performance of the cipher feedback mode in terms of the probability that part of or the whole ciphertext can not be successfully decrypted, and derives the optimal number of stages to achieve the optimal throughput, given an error rate in a wireless network.
Abstract: Block ciphers encrypt a fixed size block of plaintext at a time to produce a block of ciphertext. Stream ciphers encrypt stream data, such as voice or Telnet traffic, one bit or more bits at a time. The cipher feedback mode is a stream cipher implemented by a block cipher via multiple stages, and in each stage one bit or a number of bits of plaintext are encrypted at a time. In this paper, we study error performance of the stream-based cipher feedback mode in an unreliable wireless channel in terms of throughput. We model performance of the cipher feedback mode in terms of the probability that part of or the whole ciphertext can not be successfully decrypted, and the throughput by adopting the cipher feedback mode. We explicitly derive the optimal number of stages in the cipher feedback mode to achieve the optimal throughput, given an error rate in a wireless network. We also prove that for the cipher feedback mode, the whole ciphertext is successfully decrypted if and only if the whole ciphertext is successfully transmitted.
85 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2018 | 1 |
| 2017 | 8 |
| 2016 | 12 |
| 2015 | 14 |
| 2014 | 11 |
| 2013 | 13 |