We analyse the security of new hash functions whose compression function is explicitly defined as a sequence of multivariate equations. First we prove non-universality of certain proposals with sparse equations, and deduce trivial collisions holding with high probability. Then we introduce a method inspired from coding theory for solving underdefined systems with a low density of non-linear mon...

However, GPR fails to note that a very similar result giving lqǫ-security was proved earlier in our paper “Another look at HMAC.” GPR acknowledges our main theorem, which gives lǫ-security under a stronger PRF-assumption, but omits any mention of our Corollary 10.3, where we proved that lqǫ-security under the weaker assumption follows from the theorem. GPR can correctly claim that their result ...

In [1], four different DRBGs are recommended for cryptographic purpose. Each generator is based on some underlying cryptographic concept. The article examines each of the concept to determine what are the necessary and sufficient conditions for the DRBG to be secured in its generation process. In addition, the effects of failure of typical cryptographic requirements of each underlying concept a...

Some message authentication codes (MACs) are vulnerable to multiple forgery attacks, in which an attacker can gain information that allows her to succeed in forging multiple message/tag pairs. This property was first noted in MACs based on universal hashing, such as the Galois/Counter Mode (GCM) of operation for block ciphers. However, we show that CBC-MAC and HMAC also have this property, and ...

WiMAX networks have advantages over the wired network, such as convenience, mobility, and flexibility. The security concerns in this network may prevent its further widespread adoption. Hence, improving the security of WiMAX is of considerable importance. In WiMAX networks by providing security features like authentication, authorization and encryption. The absence of proper authentication mech...

With the rise of Internet Things, fog-to-cloud computing has emerged as a new cutting-edge approach (IoT). Except for cloud service provider, necessitates participation additional entities, such mobile sinks and fog nodes (CSP). As result, storage integrity audits will differ from standard auditing. Tian et al. completed first stage in developing public auditing system computing. However, becau...

Storing HMAC and IV informtion in a drive’s NVRAM is costly. It would require 54 GB of memory to store this information for a 1 TB drive. Additionally, we do not want to store this information on disk because of the need for fast, parallel access to metadata for policy decisions (e.g., access decisions for information flow labels). We thus require methods of mitigating NVRAM storage costs. We g...

The paper proposes extensions to cryptographic hash algorithms, such as SHA, that add support for parallel processing of a single message. The goal is to take concepts from tree hashing and apply the parallel performance benefits to a single data buffer in a single threaded core of a modern microprocessor. Additionally, a method for applying the Multi-Hash concept to HMAC is suggested. The pape...

Security Engineering: A Guide to Building Dependable Distributed Systems Ross Anderson Wiley Computer Publishing This is an upper-level undergraduate, first-year graduate course on network and computer security. This course introduces the principles and practices of cryptography and network security. The first half of the class content covers basic cryptographic methods, key distribution, and p...

This paper examines possible modifications to indirect key management schemes that may improve their performance and efficiency for use within access hierarchies. A new method is proposed which uses a dedicated HMAC construction as the key transformation function, a new addressing strategy to improve accessibility verification, and a cached key update strategy which seeks to minimize key update...