Posts with the tag Blockchain

  • What is a derivation path, or what does my wallet show a different address?!

    In the crypto ecosystem, a derivation path is a way to generate multiple unique addresses from a single root seed phrase. This is achieved using a standardized mathematical algorithm called Hierarchical Deterministic Wallets (HD Wallets).

  • Ledger Error Codes - Ledger device UNKNOWN_ERROR

    I’m currently working on rLogin, which is an application that connects a developer’s dapp to the user’s wallet. As part of the development work, we are implementing hardware wallets. I worked on the Ledger hardware implementation and during the process, I came across multiple error codes that didn’t have an explanation. After Googling them, I came up with nothing, so this post will be a work in progress of the codes that I have discovered:

  • Add a custom chain or ERC20 coin to MetaMask

    MetaMask recently announced that it had opened up its custom networks API for developers to use. This means that you can help users connect to your non-Ethereum network much easier. Rather than the user typing in the Network Name, RPC URL, ChainId, etc., you can fill it out for them!

  • Checksums are for humans, not computers

    Checksums are a method of capitalizing certain characters in an address for a specific EVM network. This includes Ethereum, Ethereum testnets, RSK, and its testnet, Binance Smart Chain, and others. It is meant for users to confirm that an address is for a specific network. Once passed to a web3 provider, server, or blockchain, checking the checksum is no longer needed.

  • Tracking COVID Vaccinations using Verifiable Credentials

    COVID Vaccine

  • Using Brave with the RSK Network and Register a .RSK domain

    The Brave browser is gaining popularity for its privacy features and built-in crypto wallet. With Chrome and Firefox if a user wants to connect to the Ethereum network they need to download a third-party plugin such as MetaMask or Nifty. The wallet inside of Brave is based on MetaMask’s open-source code. The Browser’s wallet comes connected to the Ethereum mainnet and multiple testnets. You can add a custom network which is how we are going to add RSK.

  • A cryptocurrencies primer

    With Bitcoin passing $11,000 recently (October 2017) I had a few friends reach out and ask about Bitcoin. As many of you know, I completed a Masters in Digital Currency from the University of Nicosia in the spring of 2018. This post serves as an introductory primer to cryptocurrencies for non-technical folks. I will attempt to stay at a high level and will talk about cryptocurrencies as a whole rather than Bitcoin individually. There are many areas that I skim over (such as mining and proof-of-stake) which will be a separate blog post after this one.

  • Public Decentralized Insurance Co-op

    A decentralized health insurance co-op could be setup with the mission of providing health coverage to its members. It would operate similar to a non-profit where the focus is on the members and not shareholders. The co-op would use a blockchain as its data structure and each user would run a node with software that would allow then to submit claims, payments and vote. A block would be created on average every 24 hours with a term period being every 30 blocks, or roughly a month.

  • Bitcoin Is Money

    The following are two essays that I wrote for a Banking and Finance class for my Masters in Digital Currency. The assignment was two short essays, one on why bitcoin is money and another on why bitcoin is not money. Both have been edited slightly.

  • Certificate of Accomplishment, DFIN-511 Introduction to Digital Currencies

    The University of Nicosia uses the Bitcoin blockchain to verify the authenticity of certificates that have been awarded.

  • What is the average amount of time between blocks mined?

    I am taking an online class through the University of Nicosia in digital currencies and covers Bitcoin and the Blockchain. It is a free MOOC and can also be used as credit towards their Masters in Computer Science.

    During the Live Q&A section on October 3rd, 2016, there was a question about the timing between blocks being mined. It was suggested that we look at the previous 2016 blocks to see what the average time between blocks mined.

    The Bitcoin protocol is set to average the time to be 10 minutes between blocks. Every 2016 blocks the network readjusts the difficulty so the average time blocks are mined is 10 minutes. If the average time is longer than 10 minutes then the difficulty decreases, if the average time is shorter than 10 minutes the difficulty increases.

    I wrote a small JavaScript script to parse Blocktrail’s API to get the previous set of 2016 blocks and convert it to a CSV. I opened that file in Excel and created the chart and the results below.

    The blocks started at 429408 and finished at 431423. The difficulty was set at 225,832,872,179.46.


    Time it took to mine blocks 429408 to 431324

    The average time to mine a block was 563 seconds or 9:23. The longest time was 1:17:36 and the shortest was less than a second.

    Because the average time to mine was less than 10 minutes, the difficulty was increased starting at block 431424 to 241,227,200,229.99

    The Code

    I posted the code up on GitHub if you are interested in contributing.

  • Use of Blockchain for Monitoring, Identification and Notification of Population Health Trends and Outbreaks

    In July 2016, the Department of Health and Human Services put out a call for whitepapers about using the blockchain in health care. I had used the Bitcoin blockchain but hadn’t considered how the blockchain could be used outside of a ledger system.