Google USD stablecoin on Hedera Hashgraph sooner than Libra?

Google has just joined the Hedera Hashgraph governance council. As Libra, Hedera Hashgraph is consortium-based. Actually, the CEO of Hedera Hashgraph complained that the governance model was copied after meeting Facebook a while ago with an ad on the Wall Street Journal as seen in the following link:

Hashgraph took out a full page ad in the WSJ sarcastically "thanking Facebook" lmao pic.twitter.com/AO6AxMJyw8

— Rob "Crypto Bobby" Paone (@crypto_bobby) June 22, 2019

 From a technical point of view, Hedera is not based on a blockchain: it is based on a hashgraph, which another type of Distributed Ledger Technology (DLT) than a blockchain. One of the technical advantages of a hashgraph is that it reaches a very high number of transactions per second (TPS) compared to a blockchain (not considering layer 2): 100 000 TPS for Hedera Hashgraph compared to around 1000 TPS for Libra. A high TPS is important for the global payment application domain, for example, Visa/Mastercard usually needs 2500 TPS.

Both DLTs are taught as part of the blockchain, cryptocurrencies and decentralized finance course that Dr. Jean-Marc Seigneur, President of Reputaction, leads at the University of Geneva with official European (ECTS) credits and that can be attended via Skype, no need to be in Geneva. Registration to the course is open here: https://www.cas-blockchain-certification.com/en/cas-blockchain-switzerland

In addition, to be part of the governing council and contributing to the nodes and technology via features on its cloud, Google could push for the creation of a stablecoin on top of Hedera Hashgraph. A stablecoin is a cryptocurrency coin that has a stable value.

Dr. Jean-Marc Seigneur, President of Reputaction, with co-authors published in 2017, at an International Telecommunication Union (ITU) event, a paper on stablecoins based on a basket of fiat currencies. Libra chose this type of approach for its stablecoin in 2019. However, given the regulatory hurdles that Libra has faced with such an approach that allows the consortium to rebalance the percentage of each currency in the basket in order to maintain its global value, the Google Hedera Hashgraph stablecoin could be backed by US dollars only. It would be difficult to forbid such an approach because many other existing stablecoins are backed by USD only already. Another advantage for the USD-backed Google Hedera Hashgraph stablecoin from the point of view of the regulatory issues may be that the non-profit foundation governing Hedera Hashgraph is based in New-York. US regulators may be more favorable to a stablecoin whose foundation is based in the USA and based on USD only.

Finally, based on Dr. Jean-Marc Seigneur’s previous study in GAFAM trust (linked here), Google is the second most trusted GAFAM, Amazon being the most trusted.

Which DLT will be chosen by Amazon for its Amazon stablecoin? Will it be based in the USA or in Geneva as chosen by Libra? What about the Chinese BATX? When WeChat will implement the China CDBC (Central Bank Digital Currency)?

Exciting times ahead, including for Reputaction products development, which may be unveiled soon!

Facebook Coin or Amazon Coin Trust Survey with replies from more than 2100 Americans

Would Americans trust more Facebook coin or Amazon coin? More than 2000 Americans have participated in this survey

Facebook has recently created in Geneva a subsidiary company, Libra Networks, for its crypto-currency with code name Globalcoin. Being based in Switzerland, known for its neutrality, quality, security and openness to crypto-tokens, is the first advantage with regards to the trust that customers would have in a Facebook coin. Social trust is of utmost importance for its success beyond the technical trust that crypto-currencies provide. Unfortunately, Facebook brand is already at the center of a long history of mistrust events that have to be taken into account when estimating its potential to succeed as the first large-scale used crypto-currency.

To estimate the trust that people have in Facebook, Dr Jean-Marc Seigneur, CEO or Reputaction, has extended his previous 2017 survey on Bitcoin trust. As in 2017, more than 2100 American adults answered an online survey in March and April 2019. To broaden the survey results, more than 2100 French adults also responded to the same study, but this time translated in French. The surveyed asked short unambiguous questions starting with “Do you trust…” to avoid any cultural bias in the notion of trust. In addition to asking “Do you trust Bitcoin?”, the GAFAM were targeted: “Do you trust Facebook?”, “Do you trust Amazon?”, “Do you trust Microsoft?” and “Do you trust Google?”. “Do you trust LinkedIn?” was asked rather than “Do you trust Apple?” because Apple hadn’t released its new crypto kit and connect functionalities at the time of doing the survey, and an instructive trust behavior is to know if someone is ready to log in to a third-party service with credentials from an initial service. Facebook has provided the Facebook Connect feature for several years, which is also the case for Google, Microsoft, Amazon, and LinkedIn. A respondent could choose among four different randomly ordered answers, for example, “Do you trust Facebook?” could be answered by the following responses:

1. I trust Facebook
2. I neither trust nor distrust Facebook
3. I distrust Facebook
4. I don’t understand the question

The following image summarizes the results of the survey.

On the one hand, we see that Amazon is the most trusted among the studied GAFAM with more than 45% of the respondents trusting Amazon and only 9% distrusting it. 35% neither trust nor distrust Amazon, and only around 10% haven’t understood the question. It isn’t surprising that people trust Amazon because lots of them have experienced reliable delivery of products through Amazon. Consistent successful delivery creates trust even if Amazon has its issues in the press: replacing humans by robots, the environmental cost of shipping, employees problematic working conditions… Daily products delivery is a significant trust advantage that the other GAFAM don’t have.

On the other hand, only around 12% of the respondents trust Facebook, and approximately 40% of them distrust Facebook. Facebook gets almost the opposite results of Amazon. Only Bitcoin is less trusted than Facebook. It is worth noting that between 2017 and 2019, trust in Bitcoin has decreased noticeably from 8% to 6% even if more people seem to understand Bitcoin given that the percentage of people who answered “I don’t understand the question” has reduced from around 30% to 20%.

Although the results of this survey indicate that Amazon is the most trusted of the surveyed GAFAM, Facebook has still the main advantage of being the only GAFAM who is releasing its coin. People have no other GAFAM coin choice. Amazon coin would undoubtedly win the social trust aspect, but it doesn’t exist. When people have no choice, they choose what is available, and Facebook coin is the only planned GAFAM coin at the time of writing. The other GAFAM should try to release their crypto-currency at the same time as Facebook, especially Amazon, which is in a leading position. Otherwise, Facebook is likely to win the GAFAM crypto-currency market in the long term because as people will experience a frictionless Facebook coin with much less hurdle and fees than with traditional banking, their trust in Facebook as a payment entity will change positively, even more, if there is no competition.  Competition outside of the GAFAM isn't mentioned although some projects exist because the GAFAM have already hundreds of millions of users. One may refer to Tether (USDT), but its trust level is already shallow in the cryptocurrency world. Although too small, GLOBCOIN GLX is worth mentioning because Dr Jean-Marc Seigneur has worked on it. As Facebook, GLOBCOIN GLX is meant to be much more stable than Bitcoin thanks to linking the crypto-token to a basket of currencies. Dr Jean-Marc Seigneur presented such a solution in October 2017 at the International Telecommunication Union standard conference on digital currency with my co-authors Hélie d'Hautefort et Giuseppe Ballocchi. The full paper can be downloaded here: https://archive-ouverte.unige.ch/unige:97657

A success of Facebook coin, which is based in Geneva, would be welcome because it is close to Reputaction company on the French border: it would further foster Geneva blockchain ecosystem. Reputaction provides solutions for decentralized trust, for example, for trustworthy decentralized products certifications as part of Reputaction relational value decentralized marketplace with hardened crypto-wallets. The patent-pending hardened crypto-wallets allow buyers and sellers to make KYC-AML-enforced Bitcoin/token transactions only with good guys, in real-time and even offline: they are an alternative solution to blockchain layer two solutions such as Bitcoin lightning networks. For more information on these Reputaction products, have a look here:  https://www.reputaction.com/en/products and you can participate to the current Reputaction token contest here: https://app.reputaction.com/en/. Reputaction is currently seeking private equity investment to expand its patent beyond France and to continue its commercialization and development, as shown on the following architecture overview image. 

Now that Apple is focusing on connect and crypto kits, which can be leveraged by Reputaction patent-pending hardened crypto wallets, the next edition of this survey may include “Do you trust Apple?” as well 😉

If you want to know the next updates of the survey, you can subscribe to Reputaction newsletter https://www.reputaction.com/en/newsletter

Thailand Seminar on Blockchain, DLT and Cryptocurrencies

Reputaction Thailand Blockchain Seminar Feedback

Dr. Jean-Marc Seigneur, President of Reputaction, has been to Bangkok during the first week of September 2018 to teach blockchain, Distributed Ledger Technologies (DLT) and cryptocurrencies to around 70 delegates of the Ministry of Digital Economy of Thailand and International Telecommunication Union (ITU).

So many Asian countries with interesting DLT use-cases

Most of the delegates were from Asian countries, e.g., Thailand, Laos, Bhutan, Indonesia, Malaysia or India and all came up with very interesting DLT uses-cases. During the first days they were taught the basics of blockchain and DLT including terminology, consensus algorithms, blocks versus directed acyclic graphs (DAG), 51% attacks, tokenomics... Then, they split into teams and had to come up with a convincing use-case of DLT. For example, they presented an Hyperledger-based halal certification system, permissioned between each Asian country administration in charge of halal certification, in order to avoid the same halal product manufacturer to redo similar certification in each country, saving time and increasing transparency, the market being worth several billions USD. Another team proposed an Ethereum-based permissionless system in order to better track the use of public money given to agencies in India for public services such as health or education.

Investments in blockchain and ICOs legal aspects in the region

As in many other parts in the world, initial coin offering (ICO) legal aspects are discussed and considered as a new way of investment, especially when the projects involve blockchain and DLT that need incentive mechanisms. Thailand is quite advanced and open regarding ICOs because it has prepared new laws for the fields and should launch an ICO online portal by the end of 2018 where legitimate projects would be validated and then would be assured to get a bank account in Thailand. Dr. Jean-Marc Seigneur had also the opportunity to meet several other cryptocurrencies and blockchain investors and stakeholders. In the business centre of Bangkok, Dr. Jean-Marc Seigneur met the CEO of Everex, one of the first blockchain-based banking solutions providers based in Thailand, with great office view as shown in the image below. Everex has already successfully run its ICO based on its EVX token, also known for its Ethereum tokens explorer called Ethplorer. It is worth noting that other Asian countries such as the Philippines are quite active and favorable regarding ICO legal aspects. Dr. Jean-Marc Seigneur has already taught at the University of the Philippines Cebu and knows the good competencies of programmers in the Philippines, which could make it an attractive centre for DLT development if the legal aspects are finalized. Reputaction will continue to look at the DLT opportunities there and may even strengthen its DLT development team there if the right opportunity arises.

An official certificate for blockchain (NEO, Ethereum…) and Distributed Ledger Technologies (DLT)

In addition to be the founder of the patent-pending Reputaction hardened crypto wallet enforcing KYC & AML for any Bitcoin/Ether transactions, even instant and offline, I’m the director of a new postgraduate course at University of Geneva, official Certificate of Advanced Studies (CAS) worth 12 European ECTS credits, teaching decentralized applications (dApps) with blockchain and DLTs.

A difficult question for such a course is actually to choose the most appropriate available platforms to teach dApps development with blockchains and other Distributed Ledger Technologies (DLTs).

I have already compared dApps platforms in a previous post but this time the teaching aspect is more important. Such a postgraduate course is done over a short period of time, on site or online, in this case on Fridays and Saturdays mornings from mid-January to mid-May. There is no time to teach the basics of programming and of course if the dApp development platform uses well-known programming tools, it helps a lot to facilitate the learning curve.

Which dApp dev platform uses well-known development tools?

One well-known Integrated Development Environment (IDE) is the Microsoft .NET C# Visual Studio and Team Services, which has even recently bought Github. Being able to develop smart contracts and dApps with such a mature and complete IDE is from my point of view a real asset.

There are a few blockchain dApp dev platforms that are well integrated with .NET and especially C# its main programming language. NEO and Stratis are 2 blockchain dApp dev platforms very well integrated with C# and .NET. NEO has its own NUGet package that can be easily added to Visual Studio as well as a compiler and even an emulator, which doesn’t require to have access to a deployed blockchain such as the mainnet, testnet or privatenet. As you can see on the images below, on June 20th 2018, I have had the pleasure to organize the first NEO development workshop and meetup at University of Geneva in the presence of Da Hongfei, Founder of NEO, and Caterina Zhang, NEO Head of Marketing & Communication.

There was also Peter Lin, NEO Head of R&D, who underlined that NEO Python implementation had even a greater community participation than NEO C# main internal implementation. He said that Erik Zhang, NEO co-founder, is more a fan of C#, as I am, especially because I think that strongly statically typed languages are more secure, with fewer bugs at runtime, which is important for smart contracts. However, Peter also emphasized that Python has been chosen as the main programming language to be taught to Chinese students, such large adoption should be taken into account. Anyway, the good thing with NEO is that it has several implementations including C#, the most up-to-date one because it is the main internal implemenation, and Python, which is also well up-to-date thanks to open source community contributions. Sometimes having too many implementations is difficult to maintain. Recently NEO has had some issues regarding its code stability. In my opinion, great care should be taken for backward compatibility with previous code, using deprecated methods warnings rather than methods hard crashing. It is also not clear if NEO will have all of its own building blocks as described in its original whitepaper such as identity management or through external projects, e.g., now it seems that ONTology is supposed to provide identity management in relation with NEO but the relation is unclear as it has its own tokens and implementations. The NEO fees structure needs also some stabilityand drastically changing fees structure wouldn’t allow developers to be able to confidently choose NEO for long term projects. Smart contract deployment on NEO was quite expensive, requiring 500 GAS at the beginning but then its usage based on the 10 first GAS free was appealing for some longer term projects, reducing their cost in the long term. Due to abuse of these 10 first GAS free and fewer projects willing to pay 500 GAS at the beginning, the co-founder Erik Zhang has hinted that NEO pricing model could change a lot rather than just be adjusted, which should be avoided IMHO. Aligning NEO pricing model on Ethereum pricing model isn’t the only solution because computational trust could be tried to exclude malicious behaviours and encourage positive behaviours whilst still keeping the original pricing model, which has its own advantages compared to Ethereum-like pricing model. Anyway NEO with its C# .NET integration is still a valuable blockchain platform contendant for the course though.

Stratis has also a valuable C# .NET integration and mainnet blockchain launch based on proven Bitcoin building blocks and additional sidechains. It will be easier for students of the new University of Geneva course to switch to Stratis if needed because they will have already learnt a previous blockchain with the same IDE and programming language.

However, the new course has the aim to give an overview of different blockchains/DLTs and their development environments. It is the reason that Ethereum will also be taught because it is the most well-known dApp/smart contracts platforms with a quite attack-resistant public blockchain (at least as long as Proof of Work is used). Ethereum has also experienced an important gain in tokens value, in this case Ether, and volatility but Ethereum has succeeded to maintain its initial approach to fees for smart contracts deployment and usage. The learning curve for the students will be longer for Ethereum because they will have to learn the new Solidity programming language, which is also more difficult to use without bugs. The development environment is improving though, for example, with proven Ethereum smart contracts templates by Zeppelin and Truffle, a popular development framework for Ethereum. The students of our new Certificate of Advanced Studies (CAS) will leverage these tools too.

We have mentioned above that 2 decentralized application development frameworks with blockchains will be taught during the course but what about other with other types of DLTs such as Directed Acyclic Graph (DAG), tangles… There aren’t so many proven options for dApps developments with non-blockchain-based DLTs. We are at the moment discussing with Hashgraph Hedera because Swirlds the private company behind its patented Hashgraph technology has already used it for many real use-cases in different applications domains, although in permission-based/private settings. Hedera the open version has still to prove itself in public settings, especially regarding attack-resistance. From the point of view of the course, the learning curve shouldn’t be to high because Hashgraph has a Java implementation, which is a well-known programming language, and Hedera will also be based on Solidity, already taught during the course. Another interesting DAG that is considered is the recent Fantom platform for building dApps with DAG, although in very early stage for now and with claims (reaching 400 000 transactions per second) needed to be validated by peer-review. IOTA tangle theory will be quickly covered because it is a well-known non-blockchain project but it isn’t really a fully fledged dApp development framework.

Talking about peer-review, if you are building a decentralized app or new blockchain/DAG/crypto-currency and would like to get peer-review, I recommend that you submit an article to the ACM SAC 2019 DAPP track with deadline on September 10th 2018 because your work will be then published the official ACM Digital Library and you will be able to claim that it has been peer-reviewed. We are also welcoming sponsors to be listed on the ACM SAC 2019 DAPP track Website and CFPs and/or on the new blockchain, DLT & dApp course Website. Presentations of innovations in the field at University of Geneva are also possible. Contact me for more information!

Participation to Blockchain and DLT Standardisation

As you can see in the image below, I (Jm, founder of Reputaction, identifiable thanks to the black hat ;-) have participated as expert member to the International Telecommunication Union (ITU) initiative for standardisation of blockchain and more generally Distributed Ledger Technologies (DLT). It is interesting to see that other members come from major Chinese companies such as Tencent and Huawei. A smaller size but more well-known Chinese company in the field of DLT was also present, namely, Onchain, which has strong relationships with NEO that is the blockchain chosen and used by Reputaction. Of course being organized by the ITU, a good number of telecom operators have joined the initiative such as Swisscom, Rostelecom, Türk Telekom…

We have worked on the technology reference framework and DLT evaluation criteria. The goal is to not only cover blockchains but also other DLTs such as Directed Acyclic Graph (DAG), e.g., Fantom or Hashgraph Hedera. I am in contact with both Fantom and Hashgraph and they might join the initiative. Anyway, trustworthy independent evaluation is important, e.g., especially, when projects announce hundreds of thousands of transactions per second, still with high attack-resistance and without high energy consumption. If you’re part of a project willing to join that DLT standardisation initiative, contact me on LinkedIn and I may help you.

dApp Platform Selection

Decentralized Application (dApp) Platform Selection

In the past few months the Reputaction team has worked a lot on software development in parallel to business development. After being close to release the first Minimum Viable Product (MVP) based on a Web application with cloud-based storage, the next step is to store information on a public blockchain to reach an unprecedented level of transparency regarding trustworthy product information including supply-chain, workers, buyers, sellers and reviews information. Related competitors, such as TripAdvisor, are known to forbid access to its reviews information, only sharing some information through a closed Application Programming Interface (API) to few external partners. Worse, TripAdvisor reviews are known to be flawed because no verification of the customer experience is done. For example, a number of fake restaurants have succeeded to be ranked first on TripAdvisor in the recent years. In order to increase transparency and trustworthiness, Reputaction relational value product information will be stored publicly on a blockchain. We have worked on defining which blockchain seems to be the most appropriate for this task. Below we first discuss how the most promising decentralized application (dApp) platforms compare. Then, we explain our current roadmap for the Reputaction dApp implementation. 

Ethereum, NEO, Cardano, ICON and Hashgraph (Hedera) Comparison

Ethereum has been the first dApp platform to be created. Following its success, a number of challengers appeared: NEO, the "Chinese Ethereum"; Cardano, the "Japanese Ethereum"; ICON, the "Korean Ethereum" and Hashgraph (Hedera) a patented solution related to blockchain but technically different. We have compared in detailed these different dApps in several videos on the YouTube Reputaction channel. We summarize below the main advantages and disadvantages of each of these dApp platforms:

• Ethereum: 
• Advantages: open-source; largest community of blockchain developers; several dApps already running in production; attack-resistance with Proof-of-Work (PoW)
• Disadvantages: difficult to program (new Solidity programming language with high-level checks as older traditional programming languages); fewer developers than for traditional programming languages; cost of each blockchain operation or storage; uncertain attack-resistance of the newly planned Proof-of-Stake (PoS); energy cost of PoW; no Know-Your-Customer (KYC)/Anti-Money-Laundering (AML) of initial token holders; low transaction speed compared to other competitors, especially as long as PoW is still used
• Cardano:
• Advantages: peer-reviewed by a good number of academics regarding its attack-resistance and other properties; KYC of initial token holders
• Disadvantages: it has still many building blocks to be developed before being able to deploy a dApp on its blockchain; it uses a programming language (Haskell) that is not well-known by many developers; no AML of initial token holders
• NEO: 
• Advantages: easy to program because based on a well-known traditional development platform with many developers, i.e., .NET C# (Java and other languages also possible); several dApps already running with a medium-size community of open-source developers and real private blockchain projects linked to OnChain in China; no cost for blockchain operations and storage below 10 GAS; average transaction speed compared to other competitors 
• Disadvantages: strongly linked to China and OnChain private company; doubts concerning its attack-resistance and decentralization technical properties; expensive deployment initial cost of the dApp smart contract, i.e., 100 GAS plus 400 GAS if storage is required and plus 500 GAS if dynamic call is needed (1 GAS costs 15$ at time of posting); no KYC/AML of all token holders
• ICON:
• Advantages: should be easy to program when the English documentation is ready because based on Python, which is a well-know programming language with many developers already; several real private blockchain projects in South Korea developed on its Loopchain core engine; high transparency of its tokens because all token holders have had to pass KYC/AML checks; average transaction speed compared to other competitors
• Disadvantages: strongly linked to South Korea and Loopchain private company; currently lack of English documentation; doubts concerning its attack-resistance and decentralization technical properties; the cost of smart contract deployment and use is unknown yet
• Hashgraph (Hedera):
• Advantages: easy to program because based on a well-known traditional development platform with many developers, i.e., Java (in addition they say they will also provide a Solidity version); very high-speed compared to competitors; formally proven in permission-based settings, i.e., private blockchain 
• Disadvantages: unproven attack-resistance in permissionless settings, i.e., current public Bitcoin or Ethereum blockchain (even if they argue their PoS-like approach is attack-resistant, it hasn't been peer-reviewed); strongly linked to the Swirlds private company, which has patented hashgraph; not ready yet for production as the Hedera ICO hasn't been done yet

Choosing the most appropriate dApp platform for a MVP

A MVP means that it is a first version of a product with the minimal number of features. Usually, it is also part of an agile development approach meaning that the goal is to release the MVP as soon as possible. If the dApp platform requires a lengthy learning-curve by the available developers, then releasing soon cannot be done. Another usual requirement of a MVP is that it shouldn't be too costly to build and run. The attack-resistance, transaction speed and decentralization aspects don't need to be stronger than what the current market expects, especially if the MVP doesn't have to use the blockchain for too sensitive or fast operations and storage. Later on, if other features must be added to the MVP along with more resources and time, it may still be possible to port it to another dApp platform. 

Based on the above comparison between Ethereum, NEO, Cardano, ICON and Hashgraph (Hedera), NEO seems to provide the best dApp platform for a MVP. First, the learning-curve is short because it is integrated in the well-known .NET development platform. Second, although the cost of initial deployment may be high for some project, the fact that operations and storage below 10 GAS are free may be interesting for projects that rely on many small operations and storage. Third, attack-resistance, transaction speed and decentralization aspects may not be perfect but they are currently accepted by a good number of stakeholders and are sufficient for MVP without sensitive operations and speed requirements.

It is the reason that Reputaction, which has no high-speed requirement, is currently developing its MVP with NEO. We are still in good discussion with ICON for further developments, especially because all its tokens are linked to token holders who passed KYC/AML, which is important from a long term legal point of view. So far, Ethereum hasn't been considered further, mainly due to its difficult programming language, associated learning curve and long-term cost of each operation and storage. 

In addition to this blog, you can follow us on Reputaction Instagram, Reputaction Twitter, Reputaction Telegram, Reputaction Reddit and Reputaction YouTube.

Intervention aux Etats Généraux du Tourisme de Genève ~ Crypto-Friendly Tourism Presentation at a Major Political Event in Geneva

(English version below the French version ~ Version anglaise après la version française)

Présentation aux Etats Généraux du Tourisme de Genève

Dr. Jean-Marc Seigneur, Président de Réputaction, a été invité à présenter sa vision du futur du tourisme dans le cadre des Etats Généraux du Tourisme à Genève en mai 2018, lancé par l'homme politique Pierre Maudet, Conseiller d'Etat à Genève. Découvrez sur son article sur LinkedIn les grandes lignes de son intervention qui parlera entre autres du rôle des crypto-monnaies et du lien avec le projet du token Reputaction :
https://www.linkedin.com/pulse/towards-geneva-crypto-friendly-tourism-jean-marc-seigneur

***

(English version)

Invitation to present at the event on the future strategy for Geneva tourism

Dr. Jean-Marc Seigneur, President of Reputaction, has been invited to present his vision at the major political event on the future of tourism for Geneva in May 2018 by the politician Pierre Maudet. Among other technologies, he underlines the role of crypto-currencies for international tourism and where the Reputaction tokens can apply.  Discover his first thoughts on the subject by clicking on the following link to his article on LinkedIn:
https://www.linkedin.com/pulse/towards-geneva-crypto-friendly-tourism-jean-marc-seigneur