Back to Table of contents

Primeur weekly 2015-01-26

Exascale supercomputing

BSC and Intel extend research collaboration on systems behaviour analysis and prediction at Exascale R&D Lab ...

NASA scientist joins groundbreaking UK supercomputing start-up ...

Second European Exascale Software Initiative, EESI2, is organizing its final international conference ...

The Cloud

Anthem teams with IBM to strengthen IT operational performance ...

The European Space Agency builds a private Cloud platform with Red Hat ...

AccelOps' latest release delivers interactive security and performance analytics plus Cloud monitoring ...

Oracle Voice brings a mobile, speech-enabled virtual assistant to the Oracle Sales Cloud in Release 9 on smart phones ...

EuroFlash

New Head of Astroparticle Physics European Consortium appointed ...

REF signals deep impact as EPSRC announces GPB30 million for Impact Acceleration Accounts ...

New laser for computer chips ...

Graphene brings quantum effects to electronic circuits ...

Square Kilometre Array: The Cosmology Engine ...

Computer scientists from Saarbruecken improve the privacy of the Internet currency Bitcoin ...

Graphene enables all-electrical control of energy flow from light emitters ...

USFlash

DataDirect Networks again dominates as world leader in 2014/2015 TOP500 global supercomputing list ...

DataDirect Networks Storage Fusion Xcelerator (SFX) flash cache technology wins Storage Visions Award ...

UCSD study shows why protein mutations lead to familial form of Parkinson's disease ...

UC San Diego physicist Frank Würthwein joins SDSC ...

SDSC supercomputers to assist UC San Diego's 'Extreme Events' Center ...

SDSC announces UC Graduate Summer Fellowship programme ...

New wind-farm computer simulations unlock increased power generation ...

The City University of New York selects SGI to power major research projects ...

Air Force Research Laboratory's Department of Defense Supercomputer Resource Center (DSRC) to receive new supercomputer ...

Supercomputer simulations yield method for predicting behaviour of new concrete formulas ...

Oracle tackles data centre cost and complexity with next-generation engineered systems ...

A 3D view of the Greenland Ice Sheet opens window on ice history ...

Dedicated Computing joins the Intel Cluster Ready programme to offer high-performance computing cluster solutions for bioinformatics research ...

Researchers get $1.4 million to advance 'Big Data' for genomic research ...

Optimizing optimization algorithms ...

Scientists set quantum speed limit ...

New signal amplification process set to transform communications, imaging, and computing ...

Computer scientists from Saarbruecken improve the privacy of the Internet currency Bitcoin

22 Jan 2015 Saarbruecken - "Within the research community, it is well-known that the anonymity of Bitcoin can be broken", explained Aniket Kate of Saarland University, who leads the independent research group "Cryptographic Systems" at the Cluster of Excellence "Multimodal Computing and Interaction". Experts like him associate two ideas with the term "Bitcoin": Firstly, there is the on-line payment system. It consists of people using special computer programmes, so-called Bitcoin clients. As a whole, they form a network in which every transaction is registered and recorded. In this manner, neither a central banking institution nor restrictions due to national borders are necessary. Secondly, there is the currency. In the last few years, Bitcoin not only attracted media attention, but also increased unprecedentedly in value. At present, one Bitcoin, abbreviated as BTC, is worth over 200 US-dollars. The anticipated anonymity of this virtual currency relies on the so-called Bitcoin addresses. "They are pseudonyms through which users perform and publicly record transactions. If those pseudonyms can be tracked back to the real initiators, the anonymity of Bitcoin is broken", explained Aniket Kate. In collaboration with his PhD students Tim Ruffing and Pedro Moreno-Sanchez, the computer scientist has now developed a method that protects the user's anonymity, prevents fraud and can be easily incorporated into current Bitcoin programmes.

So far, users are dependent on so-called "mixing services". In theory, they should accept the Bitcoin transfers of various users as a sort of digital mediator and forward them to each of the provided addresses, but of course without revealing the client. In practice, the process is not as honorable: Sometimes the providers of mixing services steal the digital money, plus the identities of their clients are also not safe, because mixing services are able to relate the clients to the addressees.

Aniket Kate and his colleagues have now advanced the idea behind this system. With their novel approach, the users are no longer dependent on the secrecy provided by their intermediaries. Similar to the network "Tor", which allows anonymous access of the Internet, several Bitcoin users form a sort of sworn community in advance. To hide the source of their transactions, each one of them conforms to a certain pre-determined succession of actions - the so-called CoinShuffle protocol, which was developed by Kate and his team. Every participant decodes the list of recipient addresses he has received, adds his own to it and forwards the encrypted list to the next participant. This process is repeated with every participant. In this way they shuffle the order of the addresses and hence the traces to the recipient, similar to shuffling a deck of cards.

"The result is a list of addresses, which does not contain any indication of the initial client. To prevent abuse, everyone subsequently checks the released list", stated Aniket Kate. What is special about this approach is that if something appears to be suspicious or some participants try to defraud the others, the offenders can be easily exposed. To test their approach in practice, the Saarbrücken computer scientists implemented it in the programming language Python. In this way, they could prove that the additional time costs for mixing do not create any problems.

The researchers explain that with twenty participants, their method completes in less than 20 seconds. At the same time, one transaction with Bitcoin takes several minutes in any case. "To the best of our knowledge, CoinShuffle is the first solution worldwide that is immediately usable and provides anonymity without an intermediary", explained Tim Ruffing. He has already spread the word within the Bitcoin community. "Currently, several developers are reprogramming our approach to incorporate it into their Bitcoin clients", stated Tim Ruffing.
Source: Saarland University

Back to Table of contents

Primeur weekly 2015-01-26

Exascale supercomputing

BSC and Intel extend research collaboration on systems behaviour analysis and prediction at Exascale R&D Lab ...

NASA scientist joins groundbreaking UK supercomputing start-up ...

Second European Exascale Software Initiative, EESI2, is organizing its final international conference ...

The Cloud

Anthem teams with IBM to strengthen IT operational performance ...

The European Space Agency builds a private Cloud platform with Red Hat ...

AccelOps' latest release delivers interactive security and performance analytics plus Cloud monitoring ...

Oracle Voice brings a mobile, speech-enabled virtual assistant to the Oracle Sales Cloud in Release 9 on smart phones ...

EuroFlash

New Head of Astroparticle Physics European Consortium appointed ...

REF signals deep impact as EPSRC announces GPB30 million for Impact Acceleration Accounts ...

New laser for computer chips ...

Graphene brings quantum effects to electronic circuits ...

Square Kilometre Array: The Cosmology Engine ...

Computer scientists from Saarbruecken improve the privacy of the Internet currency Bitcoin ...

Graphene enables all-electrical control of energy flow from light emitters ...

USFlash

DataDirect Networks again dominates as world leader in 2014/2015 TOP500 global supercomputing list ...

DataDirect Networks Storage Fusion Xcelerator (SFX) flash cache technology wins Storage Visions Award ...

UCSD study shows why protein mutations lead to familial form of Parkinson's disease ...

UC San Diego physicist Frank Würthwein joins SDSC ...

SDSC supercomputers to assist UC San Diego's 'Extreme Events' Center ...

SDSC announces UC Graduate Summer Fellowship programme ...

New wind-farm computer simulations unlock increased power generation ...

The City University of New York selects SGI to power major research projects ...

Air Force Research Laboratory's Department of Defense Supercomputer Resource Center (DSRC) to receive new supercomputer ...

Supercomputer simulations yield method for predicting behaviour of new concrete formulas ...

Oracle tackles data centre cost and complexity with next-generation engineered systems ...

A 3D view of the Greenland Ice Sheet opens window on ice history ...

Dedicated Computing joins the Intel Cluster Ready programme to offer high-performance computing cluster solutions for bioinformatics research ...

Researchers get $1.4 million to advance 'Big Data' for genomic research ...

Optimizing optimization algorithms ...

Scientists set quantum speed limit ...

New signal amplification process set to transform communications, imaging, and computing ...