Nuggets tagged cryptography - [remove filter]
Sept. 10, 2016 (11 months, 1 week ago)
Sept. 6, 2016 (11 months, 2 weeks ago)
Feb. 24, 2016 (1 year, 5 months ago)
Jan. 30, 2015 (2 years, 6 months ago)
Nov. 17, 2014 (2 years, 9 months ago)
This non peer reviewed paper claims to progress the state of the art in cryptocurrency. Cryptocurrencies, such as Bitcoin, are digital versions of money protected from duplication and fraud by cryptography. Bitcoin uses the concept of Proof of Work (POW) to ensure the validity of the bitcoins. In essence the bitcoin owner has to perform a complex calculation to realise the money. However at lesst one weakness of bitcoin has been published, and transactions are time consuming and have some risk. This paper makes the claim that the Decrits Consensus Algorithm is superior to POW algorithms in many ways: faster transaction confirmations, truly irreversible transactions, and permanent punishments to malevolent actors - all at virtually no external capital cost. DCA is a Proof of Stake algorithm where the owner of some currency risks some of their currency to maintain the security and validity of the currency and their stake in it. At this time, the benefits of the DCA over other POS algorithms is not clear, indeed, the author of this paper is unaware of any papers describing Peercoin, Nxt, or other POS algorithm in enough detail to make a proper comparison with Decrits.This work shows that digital currency is still evolving and, despite the seeming enthusiasm for Bitcoin, more secure and usable cryptocurrencies are under development.
July 23, 2014 (3 years ago)
The Bitcoin cryptocurrency records its transactions in a public log called the blockchain. Its security depends on the distributed protocol that maintains the blockchain, run by participants called miners. Previously it was thought that the protocol was secure against colluding minority groups, i.e., it incentivizes miners to follow the protocol as prescribed. This paper presents an attack whereby colluding miners obtain revenue larger than their fair share. Rational miners would thus prefer to join the selfish miners, and the colluding group will increase in size until it becomes a majority. At this point, the Bitcoin system ceases to be a decentralized currency. Selfish mining is shown in this work to be feasible for any group size of colluding miners. The paper proposes a practical modification to the Bitcoin protocol that protects against selfish mining groups with less than 1/4 of the resources. Such result shows the need for extensive testing and protocol analysis of any cryptographic currency. Any, future flaw identified by cryptographic analysis can be a significant threat to the currency economics, but proving the security of such schemes is extremely difficult.
July 9, 2014 (3 years, 1 month ago)
NVIDIA's Compute Unified Device Architecture (CUDA) platform provides a set of tools to write programs that make use of NVIDIA's GPUs. As massively-parallel hardware devices they can process large amounts of data simultaneously and significantly speedup suitable programs. By applying this approach to the widely-used RSA cryptographic protocol, a speedup is achieved but exact performance comparisons against commercial systems are unclear. This is an important area as the bottleneck for RSA lies in the data and key size. The use of small prime numbers is a security vulnerability but the use of large prime numbers slows the algorithm as computation effort increases.
April 10, 2014 (3 years, 4 months ago)
This new encryption technique is based on the coupling functions that model the interaction between the heart and lungs and allow them to be synchronised. This provides a dynamic system such that the data is encrypted at different times and only makes sense in the context of both sender and receiver. A patent has been filed but its degree of security now needs substantial mathematical evaluation via novel cryptanalysis.
Sept. 13, 2011 (5 years, 11 months ago)
Sept. 12, 2011 (5 years, 11 months ago)