technology:private key

Cryptographic essence of #bitcoin: Part 2 — How do public/private keys work?,
▻https://hackernoon.com/cryptographic-essence-of-bitcoin-part-2-how-do-public-private-keys-work-

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Cryptographic essence of Bitcoin: Part 2 — How do public/private keys work?, Elliptical #cryptography & Proof of workLet’s find out how to create a Bitcoin AddressElliptic Curves CryptographyElliptic curve cryptography (ECC) is an approach to public-key cryptography (watch video) based on the algebraic structure of elliptic curves over finite fields.The elliptic curve below is an example of an elliptic curve, similar to that used by bitcoin.Example of an EllipticCurveThe elliptic curve technique is used to create the public key derived from the private key.How does it work:Starting with a private key in the form of a randomly generated number k, we multiply it by a predetermined point on the curve called the generator point G to produce another point somewhere else on the curve, which is the (...)

#finance #cryptocurrency #blockchain

CounterMail - protecting your privacy - encrypted pgp email webmail
▻https://countermail.com

CounterMail is a secure and easy to use online email service, designed to provide maximum security and privacy without any unnecessary complexity.

You can access your email account at any time, from anywhere in the world. Your account will always be encrypted and anonymous.

An Interview with Simon Persson - Founder of Secure Email Provider CounterMail - Unfinished ManUnfinished Man
▻https://www.unfinishedman.com/interview-simon-persson-founder-countermail-secure-email-provider

We are under Swedish jurisdiction and swedish laws, Sweden still have better privacy laws than many other countries
We don’t log IP-addresses
You can pay anonymously if you follow our instructions, or simply just use Bitcoin
Incoming email will be encrypted to your public key, which means no emails will be stored as plaintext on our server, only in encrypted format
Web based OpenPGP encryption with no possibility to disable the end-to-end encryption, passwords and decrypted texts is never sent to our server
We have an USB-key option, which gives you two factor authentication, and increased protection
Our webmail server do not have any hard drives, only CD-ROM, which means no “leakage” to any hard drive is possible
Our customers never have any direct connection to our mailserver, regardless how they connect to their account, IMAP/SMTP/webmail always connects to a diskless server (tunnel)
You can delete the private key from our server (but we recommend this only for advanced users, your private key is always encrypted on our server anyway)
We have an additional encryption layer to protect against man-in-the-middle attacks

If anyone can find any other established provider that have all our privacy and security features, we will give that person $10k as a reward!

#sécurité #vie_privée #email

How We Solved #blockchain Application User Experience
▻https://hackernoon.com/how-we-solved-blockchain-application-user-experience-1b422acb1346?source

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The Benefits of the Blockchain with the Usability of Web 2.0The promise of blockchain enabled applications is rooted in empowering users and creating positive sum games where everyone can win, without needing rent seeking intermediaries. Until now, the nature of decentralization has made blockchain applications hard to use for the average internet user.At Deconet, we’ve implemented a solution for users to control their private key without requiring these users to understand any new systems, conventions, or standards. Deconet is a marketplace where companies can get work done by elite freelancers and curated teams that leverages blockchain and programmable money,Underneath the hood, the Deconet marketplace is powered by Smart Escrow, a peer to peer, smart contract system running on (...)

#blockchain-application #user-experience #product-management #blockchain-ux

Generating #rsa Private and Public Keys
▻https://hackernoon.com/generating-rsa-private-and-public-keys-b82a06db6d1c?source=rss----3a8144

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We use SSH, HTTPS, etc., on a daily basis. These programs depend on RSA asymmetric key encryption and decryption for providing #security.Asymmetric key encryption involves two keys, public key and private key. Public key is used for encrypting the message and Private key is used for decrypting the message.In this post, we will look into how a public key and private key pair are generated using simple mathematics.We will use small numbers for simplicity.Public Key ( e, n )Public key is made up of two numbers called e and n.Generation of nGenerate two prime numbers.Prime number 1, p = 7Prime number 2, q = 17n = p x qn = 7 x 17 = 119Thus n = 119Generation of eCompute totient of n, ϕ(n) = ( p -1) x (q -1)Choose a random prime number that has a greatest common divisor (gcd) of 1 with ϕ(n)ϕ(n) = ( 7 — 1 (...)

#public-key-cryptography #cryptography #public-key

The Second #gaming Revolution Is Here
▻https://hackernoon.com/the-second-gaming-revolution-is-here-98194c050c79?source=rss----3a8144ea

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Blockchain has quickly become a buzzword in daily conversation, and it’s inspiring to see how far the technology has come since bitcoin’s debut about a decade ago. Especially for the gaming industry, #blockchain has the ability to change both the way we interact and experience games, but also offers the possibility to create new game concepts which were not possible before. Besides that, blockchain gives the ability to create tangible assets players uniquely own, stored in their wallet, secured with a private key — players are in control of the game and its assets.Players are in control of the game and its assets.The gaming space is full of younger players with a natural affinity for new technologies. This audience is eager to try out new ideas. Speaking about mass adoption of blockchain, the (...)

#token #blockchain-technology #cryptocurrency

Would you implant a #cryptocurrency wallet in your body?
▻https://hackernoon.com/would-you-implant-a-cryptocurrency-wallet-in-your-body-857149c0f188?sour

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You swipe your hand across a service desk and instantly you have paid for your item. This is a potential option facing individuals that have subscribed to the idea of subdermal implants at the point of sale.There is already a small but growing ‘body-hacking’ community that has an open mind about the idea of these subdermal implants and other Human Enhancement Technologies (HET). This growing sector aims to fuse the world of technology and the human body.Subdermal implanting is the process of placing an RFID (Radio Frequency Identification) chip under your skin. Couple this with the private key of your #bitcoin wallet and you have a ready-made payment option that is impossible to lose.Would you be comfortable having a cryptocurrency wallet as a permanent addition to your body?What if this (...)

#cryptocurrency-wallets #subdermal-implant #bodyhacking

How to Integrate #scatter Desktop Wallet into your #eos #dapps using Reactjs
▻https://hackernoon.com/how-to-integrate-scatter-desktop-wallet-into-your-eos-dapps-using-reactj

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You might already be familiar with Scatter, a web/desktop wallet that makes it easy for ordinary users to store their private key and interact with apps. Integrating Scatter into apps can be tricky and, since Scatter is improving quickly, there have been some breaking changes introduced recently. I’ve had a bunch of people ask me about integrating Scatter, so I created this tutorial on how to integrate the latest version of Scatter Desktop into your distributed EOS application.Create your Scatter IntegrationWe’re going to start by setting up Scatter inside of a Component and creating a transaction method. We’ll be able to use this anywhere in our application to enable users to sign transactions with Scatter.Create Separate Scatter File and install dependenciesMake sure you import eosjs, (...)

#react #eos-dapp

Solutions for private key management in decentralized apps
▻https://hackernoon.com/solutions-for-private-key-management-in-decentralized-apps-24f95634be16?

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How to reconcile #ethereum’s call for decentralization and users’ need for support services?On Ethereum, private keys are used to access accounts, sign messages etc. Once you lose access to your private key, you lose access to all funds stored with that account.How is that different from losing a credit card pin code? It is you can’t ask the bank to give you a new code, because the bank doesn’t exist on Ethereum. Your funds are still credited to your address on the #blockchain, but there is no way for you to withdraw them.Accounts and [DApp-] services on the Ethereum blockchain aim to be decentralized, and no one is safekeeping access codes on your behalf.A service storing your private key in its database would be able to access your funds at any moment — just like a bank — and this is (...)

#ux-design #cryptography #dapps

How to Create Your #identity Effortlessly on a #blockchain
▻https://hackernoon.com/how-to-create-your-identity-effortlessly-on-a-blockchain-9e42a998ccee?so

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This paid story is brought to you by SafebitYou can create a social identity for yourself by creating a profile on a social networking site like Facebook. You can use that identity to seamlessly signup on Medium. You don’t have to re-enter first name, last name, etc. Medium integrates Facebook APIs and transfers your information with your consent.But, what about creating your identity on the blockchain?Creating an identity on a blockchain is not easy. Consider a #bitcoin wallet, you need to generate a private key and a public key. But, look at this public key, does it speak for you?897c59e1c04dab8748f7f9a2e2c7fd96d16bf700d389ba4153dba3d1bebdccf9You need an identity that communicates your personality or individuality.@BlockchainCoderNow compare this identity with the public key. (...)

#blockchain-identity #identity-on-blockchain

How the Blockchain Will Increase Your Mindfulness
▻https://hackernoon.com/how-the-blockchain-will-increase-your-mindfulness-f206b25e65a?source=rss

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Blockchain is quickly becoming a ubiquitous technology across just about every industry. In real estate, it is being used to compile listings, property records, and even democratized ownership of shares in properties. In healthcare, it is making the lives of medical staff and patients easier through smart contracts that grant patients private key access to signing off on operations as well as many other functions. Another area where blockchain is showing its utility is in the wellness and attention economy.New blockchain-based apps and games are capitalizing on the popularity of mindfulness culture. These applications of blockchain are fusing with the concepts of music streaming services, podcasts, and MOOC communities to reward users with currency for participating in yoga and (...)

Building Your Own #ethereum Hardware Wallet For $5
▻https://hackernoon.com/building-your-own-ethereum-hardware-wallet-for-5-c85fe7405276?source=rss

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In this post we will build Firefly hardware wallet.It’s an open-source, affordable, air-gapped hardware wallet for Ethereum you can build at home for around $5 in parts.Here is a short video of its final working model.▻https://medium.com/media/d64d81e63769cca50f33c890343c2d8b/hrefHere are some of its features:Low Cost: Build it yourself for about $5 with an #arduino, a 2.4GHz radio, an OLED display and a few odds and ends.Air Gapped: Not connected by wires and cannot send wireless signals, keeping your private key safe from hackers.Mobile Friendly: Works with any smart phone to prepare and send transactions or sign secure messages.Let’s make one for yourselfThere are a lot of options and flexibility when building a Firefly. You may design your own case or use one of our 3D printable cases. To (...)

#ethereum-wallet #blockchain #hardware-wallet

How Blockchain Will Revolutionize Education
▻https://hackernoon.com/how-blockchain-will-revolutionize-education-b095276ab0f1?source=rss----3

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Education may be the next industry to be revolutionized by blockchain. With a blockchain network that securely stores and verifies data, educational records and transactions would be securely stored and tamper-evident, and learning would be more accessible to all.In the United States, higher education in is crisis. With rising costs, more adults are carrying student loan debt, but fewer students are able to complete their degree. At the same time, people displaced by war or natural disasters often lose the records needed to verify their identify and their degrees or credentials.Blockchain would store educational records in a decentralized ledger, making them less vulnerable to loss in the wake of a disaster. All someone would need to verify their records would be private key or usb (...)

#myetherwallet Pt. 2 — How to use
▻https://hackernoon.com/myetherwallet-pt-2-how-to-use-c65136802874?source=rss----3a8144eabfe3---

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MyEtherWallet Pt. 2 — How to useThis a simple step-by-step guide in understanding how to access and use your MyEtherWallet (MEW).Now that you’ve gone through the process of creating one— let me show you how to access it. Make sure you have your USB stick handy where you saved the information we went over in MyEtherWallet Pt. 1 — Creating one.*Note: Haven’t created one yet? — Read MyEtherWallet Pt. 1 — Creating oneStep 1: Unlocking your walletYou can choose from a list of options on how to access your wallet, but I highly recommend you to log in with the “Keystore File/JSON File” option because it’s an encrypted version of your Private Key and is more secure.Step 1: Accessing your wallet with your Keystore Filea. Click on “Keystore / JSON File”b. Click on “SELECT WALLET FILE”c. Select the UTC file you saved (...)

#investing #ethereum #blockchain

The Future of Native Mobile Apps on #blockchain — What They Should Look Like, and How to Build One…
▻https://hackernoon.com/the-future-of-native-mobile-apps-on-blockchain-what-they-should-look-lik

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The Future of Native Mobile Apps on Blockchain — What They Should Look Like, and How to Build One Today.There are a lot of good reasons to have a standalone native mobile app for your ethereum token/smart contract/DApp (Decentralized App):Accessibility: Just a single tap away from the home screen means more frequent usageIndependence: You can provide custom user experience just for your users who sign in with the app specific private key. You control your own user experience and don’t have to depend on generic web browsers or generic wallet UI.Optimized UX: Relying on generic wallets or generic DApp browsers means you delegate all the transaction-related UX to the browser. This means you can’t provide an optimized, dead simple user interface specific to your DApp. With your own dedicated app, (...)

#build-a-blockchain-app #blockchain-development #blockchain-native-app #blockchain-mobile-app

Its time to get real about YOUR private keys
▻https://hackernoon.com/its-time-to-get-real-about-your-private-keys-87c1460b8bd5?source=rss----

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Governments everywhere in the world are demanding the right to decrypt communications. Every service provider can be expected at some point, to comply.As long as any centralized system keeps your secrets it has to be considered insecure.Only a system where you alone maintain your key, is necessary for any reasonable assumption of safety.Nevertheless, #security measures in 2018 are still difficult to understand and operate for the non-technical person.Simplesign is an effort to simplify and leverage the very basic essentials of public/private key usage. It’s principles are:Easy to useEasy to embedNo shared secretsIn development and any contributions consistent with the project goals are welcome.Its time to get real about YOUR private keys was originally published in Hacker Noon on Medium, (...)

#cryptography #ssh #web-development #internet

About Ring | #Ring
▻https://ring.cx/en/about/practical

Ring stores your secrets (private key for encryption and identity) only on the machine that runs it. Ring is based on the #DHT, #distributed_network_technology, avoiding the use of servers which would make you dependent on a third party and facilitate mass surveillance.

#messagerie #communication #voix #video #conference #sans_serveur #CCCP je crois bien

Beyond the Bitcoin Bubble | The New York Times
▻https://www.nytimes.com/2018/01/16/magazine/beyond-the-bitcoin-bubble.html

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(…) You may be inclined to dismiss these transformations. After all, #Bitcoin and Ether’s runaway valuation looks like a case study in irrational exuberance. And why should you care about an arcane technical breakthrough that right now doesn’t feel all that different from signing in to a website to make a credit card payment?

But that dismissal would be shortsighted. If there’s one thing we’ve learned from the recent history of the internet, it’s that seemingly esoteric decisions about software architecture can unleash profound global forces once the technology moves into wider circulation. If the email standards adopted in the 1970s had included public-private key cryptography as a default setting, we might have avoided the cataclysmic email hacks that have afflicted everyone from Sony to John Podesta, and millions of ordinary consumers might be spared routinized identity theft. If Tim Berners-Lee, the inventor of the World Wide Web, had included a protocol for mapping our social identity in his original specs, we might not have Facebook.

The true believers behind #blockchain platforms like Ethereum argue that a network of distributed trust is one of those advances in software architecture that will prove, in the long run, to have historic significance. That promise has helped fuel the huge jump in cryptocurrency valuations. But in a way, the Bitcoin bubble may ultimately turn out to be a distraction from the true significance of the blockchain. The real promise of these new technologies, many of their evangelists believe, lies not in displacing our currencies but in replacing much of what we now think of as the internet, while at the same time returning the online world to a more decentralized and egalitarian system. If you believe the evangelists, the blockchain is the future. But it is also a way of getting back to the internet’s roots.

DDoSCoin : Researchers create crypto coin with DDoS puzzle for miners

▻http://www.itnews.com.au/news/researchers-create-cryptocoin-with-ddos-puzzle-for-miners-433500

University of Colorado assistant professor Eric Wustrow and University of Michigan phD student Benjamin VanderSloot have created a cryptocurrency that uses a malicious alternative to bitcoin’s double-SHA256 hash-based proof-of-work, the computational effort required to mine new coins.

Called DDoSCoin, the alternative cryptocurrency’s “Proof-of-DDoS” allows miners to prove that they have participated in distributed denial of service attacks against preselected targets in order to create more virtual money.

DDoSCoin operates by miners opening a large number of Transport Layer Security (TLS) connections to target webservers. It would then use the signed responses as proof a connection has occurred.

Miners with DDoSCoin blocks could then trade these for other currencies, including bitcoin and ethereum.

This malicious “proof-of-DDoS” model used by DDoSCoin miners works only with sites that support TLS 1.2, but the researchers said over half of the top million websites as measured by metrics firm Alexa support that version of the protocol.

Bitcoin’s proof-of-work, a mathematical puzzle that miners have to collectively solve before more units of the currency can be created, has been criticised as a waste of resources.

The paper presented at the Usenix 2016 security conference:

▻https://www.usenix.org/system/files/conference/woot16/woot16-paper-wustrow.pdf

#DDoSCoin #bitcoin #cryptocurrency

How we built Origin CA: Web Crypto
▻https://blog.cloudflare.com/how-we-built-origin-ca-web-crypto

“In the Origin CA dashboard, we use WebCrypto to generate the key and PKI.js to create CSRs. When you click “next” in the one-click certificate dialog, your CSR is sent to the CloudFlare API. When the certificate comes back from the API, we use PKI.js to convert it to the right format and display it with your private key. CloudFlare’s servers don’t see your private key and you get to save yourself the hassle of learning obscure OpenSSL commands.”

#WebCrypto_security_JavaScript_API_clevermarks

Installer un certificat Let’s Encrypt - Métaphore, il fait froid dehors
▻https://xave.org/post/lets-encrypt

Ça fait une paie que je n’ai pas sorti un truc un peu plus geek, mais je me suis dit que ça pourrait me faire un pense-bête si je vous expliquais un peu comment j’ai fini par mettre en place ma demande de certificat Let’s Encrypt. Pour ceux que ça intéresse, ça fera un début et ça passera le temps en attendant que ça sorte de beta.

Une paire de choses d’abord : Je vise ici ceux qui bidouillent. Let’s Encrypt fournit un client pour tout faire à votre place qui vous conviendra peut-être, mais il doit avoir tous les droits sur votre serveur, c’est difficile de comprendre exactement ce qu’il fait, et moi j’aime bien comprendre ce qui se passe. comme en plus mes serveurs sont parfois bizarres, j’opte pour une procédure plus manuelle.

Je pose comme pré-requis que vous savez configurer votre serveur Apache/Nginx/autre. Je donnerai quelques exemples sur une config Apache, qui est ce que j’ai utilisé. Oui, ça veux dire mettre les mains dans le cambouis, mais ce n’est pas par manque de désir de simplifications : il FAUT modifier la config du serveur pour installer un certificat. De toutes façons, je parle de l’obtention/renouvellement du certificat, avec juste un minimum sur la config du serveur ensuite.

Un tuto de mon-ami-xave-à-moi-que-j’ai pour installer un certificat let’s encrypt sur son serveur.

#letsencrypt #tutoriel

’Worrying’ 9 Per Cent Of Encrypted Web Vulnerable To Private Key Attacks

▻http://www.forbes.com/sites/thomasbrewster/2015/11/25/encrypted-routers-cameras-vulnerabilties-cisco-huawei-motorola

The researchers, from SEC Consult, analyzed the cryptographic keys in the firmware of more than 4,000 connected devices from more than 70 vendors, detailing their efforts in a blog post today[1]. The affected “embedded systems” included internet gateways, routers, modems, IP cameras, network storage devices, mobile and Internet-connected phones, and more.

They were able to extract more than 580 unique private keys embedded in firmware across devices, a significant number of which were shared across systems.

[...]

SEC Consult discovered more than 900 devices from 50 vendors to be vulnerable. Some of the bigger names included Cisco, General Electric, Huawei, Motorola and Seagate. “Particularly bad was Ubiquiti Networks,” said Johannes Greil, head of SEC Consult Vulnerability Lab, pointing to a previous disclosure on issues with the networking equipment vendor earlier this month. A large number of routers from the likes of NETGEAR, ZyXEL, Linksys, D-Link and TrendNET were shown to be vulnerable too.

_

[1] ▻http://blog.sec-consult.com/2015/11/house-of-keys-industry-wide-https.html

Crypto Public Notary - Notarize Digital Work with Bitcoin
▻http://www.cryptopublicnotary.com

First: You create awesome content
Text, video, image, source code, contracts, deed or title. However you express yourself, whatever document you wish to record, literally, any kind of digital file works.

Next: We notarize your file
Crypto Public Notary turns your file into a Bitcoin Address in the browser. The file’s SHA256 Checksum is used as the Bitcoin private key to derive the address. You retain the original copy and your content never touches our servers. It works offline.

Then: Send some bitcoin
Send a trivial amount of bitcoin to the address. Proof of your document’s existence is now recorded forever on the Bitcoin block chain.

Retrieve your coins: You have the keys
Our process also returns a WIF private key. You can import this key and retrieve your bitcoin. Cryptographic provenance will never cost you more than miners’ fees.

Enregistrer dans la blockchain Bitcoin (horodatée et infalsifiable jusqu’à preuve du contraire) le hash d’un document, permettant ainsi de prouver son existence à un instant T. Pratique. Avant il fallait trouver un notaire, payer, attendre...

Mais reste une question : quel tribunal sera prêt à reconnaître la preuve ? Si cela arrive et que le cas fait jurisprudence, on peut s’attendre à un beau succès de ce type de solutions.

Pour mémoire, je vous parlais déjà d’un PoC similaire sous Android : ►https://github.com/ligi/SatoshiProof

#Bitcoin #Blockchain #Cryptographie #Innovation_disruptive #Notaire #Notariat #Numérique

#GPG And Me
▻http://www.thoughtcrime.org/blog/gpg-and-me

Looking forward, however, I think of GPG as a glorious experiment that has run its course. The journalists who depend on it struggle with it and often mess up (“I send you the private key to communicate privately, right?”), the activists who use it do so relatively sparingly (“wait, this thing wants my finger print?”), and no other sane person is willing to use it by default. Even the projects that attempt to use it as a dependency struggle.

Is your private key secure ?
▻http://privatekeycheck.com
#security #cryptography

A timely reminder from kyz for those who might be tempted to use some free certification service: if a certificate authority generates your private key for you and then lets you download it, RUN AWAY ! ▻http://www.reddit.com/r/programming/comments/1n5r4f/switch_to_https_now_for_free