For Germany’s central bank, blockchain has proven to be a promising – if not somewhat complicated – technology.
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PeerFlow is a newly presented system to load balance client traffic for Tor securely. To promote security within Tor, no adversary should be allowed to handle a large percentage of the traffic. Nevertheless, Tor’s relay nodes are run by volunteering individuals whose reporting of the relay bandwidths can’t be trusted. This is of great significance given the fact that Tor clients use relay bandwidths to load traffic balancing.
Creators of PeerFlow have shown that the currently used methods to predict Tor relays’ bandwidth allows an adversary, who controls little bandwidth, to attack a large percentage of client traffic. These methods include TorFlow; the current Tor bandwidth scanning system and EigenSpeed; a peer measurement system. PeerFlow offers an innovated design that utilizes a peer measurement approach to limit the ability of an adversary to boost his/her measured bandwidth while also improving the overall accuracy. The system has been proven to be fast, secure and highly efficient. PeerFlow was implemented in Tor which demonstrated accuracy and high speed within the context of a large scale network ecosystem.
An Overview of PeerFlow’s Approach:
PeerFlow utilizes a pair of relay measurement techniques which are:
1- Each relay node reports the exact number of bytes it received and/or sent from other relay nodes across the network.
2- Each relay node reports its unused, i.e. available, bandwidth.
Measurements derived from the first technique are used to predict the total amount of bytes transferred after subtracting a weight fraction, of value λ of the smallest and largest values; thus, an adversary, controlling less than λ of the network’s bandwidth, will never be able to manipulate the outcome. Measurements derived from trusted relay nodes, whenever available, are used to make sure that the estimated amounts of transferred bytes are not unreasonably low or high.
The measurements derived from the second technique will allow the network to discover the amount of available, or unused, bandwidth. However, this design is vulnerable to be lied to by an adversary, so PeerFlow is designed to consider increasing consensus’ weight of a given relay node, only after consulting the results of the first measurement technique and confirming that the first relay node has handled the expected traffic amount. Further methods are utilized to boost the accuracy, privacy and speed of the aforementioned measurements and to securely introduce new relay nodes into the system.
The authors of the paper that presented PeerFlow have demonstrated Tor’s vulnerability to adversaries controlling large relay nodes. It is clear that with the current TorFlow system for bandwidth measurement and the EigenSpeed system, adversaries can deceivingly make small relay nodes appear larger, which can markedly reduce the cost of an attack on the network. PeerFlow’s approach markedly limits an adversary’s ability to deceive Tor about the real bandwidth of his/her relay nodes, while demonstrating a performance that is somehow comparable to Tor’s present performance.
Analyzing PeerFlow’s Speed and Efficiency:
The below figure shows the measurement times’ distribution of PeerFlow over the bytes transferred.
Measurement times that are less than 14 days are shown, which comprise 96.8% of times in terms of the capacity of relay nodes. 11.5 hours represents the 25th percentile measurement time, while 70.7 hours represents the 75th percentile. Relay nodes with measurement times greater than 14 days exhibit low capacity, which is below Tor’s requirement of 100 Kb/sec for fast relay nodes and 250 Kb/sec for guard nodes. By increasing these requirements by 150%, to 250 Kb/sec for fast relay nodes and 625 Kb/sec for guard nodes, and excluding relay nodes with capacities that don’t meet these requirements, the maximum measurement time can be reduced to 316.4 hours.
The results of experimenting PeerFlow have shown that the overall dummy traffic necessary to avoid probation was in most cases equal to 2.38 KiB/sec over time and on all experiment instances, with variable standard deviation on all experiment instances too. This amount is considered rather small when compared to the median network wide goodput of PeerFlow which averages around 428 MiB/sec.
Creators of PeerFlow are willing to continue working on Peerflow to improve it in terms of scalability, and security improvement to further decrease an adversary’s ability to inflate the weight of his/her relay nodes.
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Last week, President Donald Trump signed an executive order to build a wall along the U.S.–Mexico border as he had promised during his presidential election campaign. Aside from the ethical and practical issues of building the border wall, the issue of how it will be financed was also raised by opponents during his campaign. Trump’s proposed solution to funding the wall is either to heavily tax U.S.–Mexico remittances or to fully prohibit them altogether, so that the funds needed to build the wall will stay in the U.S.According to the World Bank, U.S.–based Mexican immigrants send around $26 billion annually to their families back home in Mexico. Trump’s proposed legislation would hit Mexican families that rely on remittances from their U.S.–based relatives hard. The Mexican economy would also suffer as the multibillion-dollar remittance inflow to Mexico adds substantially to the country’s domestic spending. In light of Trump’s proposed policies to fund the border wall, remittances from the U.S. to Mexico jumped to a ten-year high after Trump’s election win in November in anticipation of possible legislation restricting cross-border money transfers to Mexico. Remittances in the month of November jumped by almost 25 percent compared to the same month the prior year, according to data collated by the Mexican central bank. Will Bitcoin Be the Answer if New Legislation Is Imposed?If U.S.–Mexico remittances using traditional channels such as banks or large money transfer operators (MTOs), such as Western Union or MoneyGram, are to be heavily taxed or severely restricted, then bitcoin remittances could offer a solution. Bitcoin allows users to send and receive money from and to anywhere in the world at a very low cost using online or mobile wallets to make the transfer. Furthermore, legal restrictions on money transfers could easily be circumvented using the digital currency, as no paperwork needs to be filed when sending money abroad. That way, both documented and undocumented Mexican immigrants would still be able to send money back home without any restrictions, should the new laws be put in place. Alternatively to bitcoin, anonymous digital currencies such as DASH, Monero or Zcash could also be used to make cross-border money transfers, should Trump decide to go through with his legislation and attempt to crack down on bitcoin remittances. Bitcoin in MexicoThe main reason bitcoin hasn’t taken any notable market share of the $500 billion global remittance market is the challenge of transferring fiat currency into bitcoin and then bitcoin back into fiat currency without having to pay too much in bid/offer spread costs. Illiquid local exchanges in developing countries can easily hike up the cost of the remittance to the extent that it would make more sense to use traditional money transfer solutions. Fortunately, for Mexican bitcoin users, there are several exchanges to choose from when needing to convert bitcoin into pesos or vice versa. Mexico’s main bitcoin exchanges include Bitso, Volabit and LocalBitcoins. Given the liquidity of both U.S-based, Mexico-based and international exchanges that residents of the two nations have access to, the costs of converting bitcoin to and from fiat currency are reasonable low, making bitcoin remittances from the U.S. to Mexico a viable solution should Trump’s remittance restrictions be enforced. Furthermore, there are bitcoin remittance companies such as Abra and Cashaa that aim to make cashing out bitcoins in local fiat currency easier. In terms of bitcoin regulation, Mexico has taken a stance similar to many of its international peers. In April 2014, Mexico’s National Commission for the Protection and Defense of Users of Financial Services issued a warning on the risks of using bitcoin stating that it is not legal tender and not regulated by the Mexican authorities. Therefore, the commission warned, “any individual or business that uses or accepts virtual currencies as a means of payment does so at their own risk and on their own responsibility because the use of this type of asset entails high volatility and potential monetary losses.” In other words, bitcoin is not illegal but the commission warns against its use due to the risks involved in dealing in the digital currency. Not surprisingly, following Trump’s election win in November, bitcoin trading volumes in Mexico on global peer-to-peer exchange LocalBitcoins and on the country’s leading bitcoin exchange, Bitso, increased substantially as Mexican bitcoin users moved funds away from the weakening peso and into a better-performing currency. Should Trump succeed in imposing strict remittance restrictions from the U.S. to Mexico, this could become the first case study of bitcoin remittance succeeding and actually become a viable means to make cross-border payments. The post Will Trump’s New Policies Boost U.S.–Mexico Bitcoin Remittances? appeared first on Bitcoin Magazine.
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ChronoBank is an up-and-coming company that seeks to disrupt the recruitment sector just as Uber and Lyft have disrupted and reinvented the ride-for-hire business.ChronoBank wants to decentralize and disintermediate recruitment by creating a P2P marketplace connecting employers with freelancers. “[We] want to create a revolution in short-term recruitment within key professions,” states the company’s website. “Our goal is to make a difference to the way people find work and are rewarded for their labour — doing so within a decentralized framework and without the involvement of traditional financial institutions.”“We are trying to streamline [the] employment process everywhere, making short-term, fair-paying engagements more attractive than long-term tenures,” Sergei Sergienko, founder and CEO of ChronoBank, told Bitcoin Magazine.“At ChronoBank, we believe in fairness, where every person can transact in the value that they themselves can generate, not just transact in fiat currency that’s issued by a central authority.” The ChronoBank concept features a new digital token: the Labour-Hour (LH), which will trade freely on the open market and will be the native unit of currency that companies use to purchase labor from professionals on the ChronoBank exchange. The company expects LH to also become, with time, “an inflation-proof asset that will be attractive to long-term investors and traders wanting to park funds overnight.”“We believe that the most valuable thing in this world is time; therefore, we are basing a currency on it,” said Sergienko. “People’s work time and skills are abundant enough to be accessible to anyone, yet scarce enough to be valuable.”ChronoBank has now integrated the Changelly app within its main wallet software. Changelly, developed by the MinerGate team, is an instant exchange app that aggregates rates from external exchanges and offers the best rate to the user, who is then able to easily and quickly exchange digital currencies without technical hassles. At this moment, Changelly permits trading in bitcoin, ether, Zcash and several other altcoins.“The ability to trade these LH tokens quickly, easily and without slippage against other national and virtual currencies is vital to the smooth operation of ChronoBank and confidence in our platform,” said Sergienko. “That is why we are working to ensure they are listed on a wide range of exchanges. Moreover, we are implementing Changelly right within the core ChronoBank wallet. That will make it incredibly easy for users to exchange LH for bitcoin and other major cryptocurrencies with practically zero delay.”In a statement, Sergienko explained that Changelly is well established and trusted in the crypto world. “It is a clean, reliable interface that we will integrate directly into the ChronoWallet to give our users another choice for trading — in this case, one that’s all about speed and convenience,” he said. The integration of Changelly will allow anyone to buy LH tokens quickly using a variety of payment options, including bitcoin and MasterCard/Visa credit cards. They can then use the tokens to buy services on ChronoBank’s exchange.The concept of using skilled work time as currency is not new. For example, Ithaca HOURS, a local currency used in Ithaca, New York, since 1991, is the oldest and largest local currency system operating in the U.S. at this time. One Ithaca HOUR, valued at $10, is recommended to be used as payment for one hour’s work, although the rate is negotiable. Ithaca HOURS are printed tokens meant for local use, and there is no standard mechanism to convert Ithaca HOURS to dollars. Therefore, the usage of Ithaca HOURS has been declining in the last few years, and the concept doesn’t seem easily extensible to current trends toward digital, global “gig economies,” of which Uber is the best-known example.The ChronoBank concept seems to improve upon Ithaca HOURS on several fronts: a digital token that can be converted to digital or fiat currencies, delocalization, decentralization and app-based ease of use. Therefore, it’s worth keeping ChronoBank under close observation and watching its next moves. The ChronoBank Initial Coin Offering (ICO), which has raised more than $3 million to date, is ongoing until February 14.The post P2P Talent Marketplace ChronoBank Adds Changelly appeared first on Bitcoin Magazine.
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