Bitcoin Explained - The Technical Side of Bitcoin

In this episode of The Van Wirdum Sjorsnado, hosts Aaron van Wirdum and Sjors Provoost discussed Bitcoin mempools, Child Pays For Parent (CPFP) and package relay. Package relay is the project that Gloria Zhao will work on as part of her Brink fellowship, which was announced earlier this week, and would make the Lightning Network more robust (among other benefits). Mempools are the collections of unconfirmed transactions stored by nodes, from which they forward transactions to peers. Miners usually select the transactions from their mempools that include the highest fees, to include these in the blocks they mine. Mempools can get full, however, at which point transactions that pay the lowest fees are ejected. This is actually a problem in context of CPFP, a trick that lets users speed up low-fee transactions by spending the coins from that transactions in a new transaction with a high fee to compensate. Tricks like these can be particularly important in the context of time-sensitive protocols like the Lightning Network. In this episode, van Wirdum and Provoost explained how package relay could enable CPFP, even in cases where low-fee transactions are dropped from mempools, by bundling transactions into packets. And they explore why this may be easier said than done.

In this episode of The Van Wirdum Sjorsnado, Aaron and Sjors discuss the Erebus Attack. The episode is a follow-up from last week’s episode on Eclipse Attacks, a type of attack that isolates a Bitcoin node by occupying all of its connection slots to block the node from receiving any transactions. Erebus Attacks are Eclipse Attacks where an attacker essentially spoofs a whole part of the internet. Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

In this episode of The Van Wirdum Sjorsnado, Aaron and Sjors discuss Eclipse attacks. More specifically, they discuss the 2015 paper “Eclipse Attacks on Bitcoin’s Peer-to-Peer Network,” written by Ethan Heilman, Alison Kendler, Aviv Zohar and Sharon Goldberg, from Boston University and Hebrew University/MSR Israel. Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

In this episode of The Van Wirdum Sjorsnado, Aaron and Sjors discuss Open Timestamps, a Bitcoin-based time stamping project by applied cryptography consultant and former Bitcoin Core contributor Peter Todd. Open Timestamps leverages the security of the Bitcoin blockchain to timestamp any type of data, allowing for irrefutable proof that that data existed at a particular point in time. Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

On this episode of The Van Wirdum Sjorsnado, Aaron and Sjors are once again joined by Ruben Somsen. This time, the trio doesn’t discuss one of Somsen’s own proposals, but they dive into a concept by Tadge Dryja called Utreexo.   Helpful links: https://www.youtube.com/watch?v=6Y6n88DmkjU   https://bitcoinmagazine.com/articles/bitcoins-growing-utxo-problem-and-how-utreexo-can-help-solve-it   Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Follow Ruben Somsen @SomsenRuben   Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

On this episode of The Van Wirdum Sjorsnado, Aaron and Sjors discuss “Assume UTXO”, a proposal and project by Chaincode Labs alumni James O’Beirne.   One of the biggest bottlenecks for scaling Bitcoin — if not the biggest one — is initial block download: the time it takes for a Bitcoin node to synchronize with the Bitcoin network, as it needs to process all historic transactions and blocks in order to construct the latest UTXO-set: the current state of bitcoin-ownership.   Aaron and Sjors explain some of the ways sync-time has been sped up over time. First, sync-time was improved through “Headers First” synchronization, which ensures that new Bitcoin nodes don’t waste time validating (potentially) weaker blockchains. In recent years, sync-time has been improved with “Assume Valid”, an optional shortcut that lets nodes skip signature verification of older transactions, instead trusting that the Bitcoin Core development process in combination with the resource-expensive nature of mining offers a reliable version of transaction history. Finally, they explain how the security assumptions underpinning Assume Valid could be extended to allow for the potential future upgrade Assume UTXO to offer new Bitcoin Core users a speedy solution to get up to speed with the Bitcoin network, sacrificing a minimal amount of security during the initial bootstrapping phase.   Helpful Links:    Chaincode podcast about the same: https://www.youtube.com/watch?v=knBHvzKsIOY   Pull request: https://github.com/bitcoin/bitcoin/issues/15605   Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

Bitcoin Core 0.21 will support Tor v3 addresses. Aaron and Sjors explain what this means and why it matters, and also discuss how new Bitcoin nodes find existing Bitcoin nodes when they bootstrap to the network. Helpful Links: * Tor V3 (onion) address support in Bitcoin Core: https://github.com/bitcoin/bitcoin/pull/19954 * the ADDRv2 message added in BIP155 that allows nodes to gossip those new Tor addresses: https://github.com/bitcoin/bips/blob/master/bip-0155.mediawiki#Specification * DNS seeds and the bootstrap problem: https://stackoverflow.com/questions/41673073/how-does-the-bitcoin-client-determine-the-first-ip-address-to-connect Timestamps: 00:00 - 00:34 - intro  1:02 - 2:10: how Tor Works 2:25 - 3:03: benefits of running a bitcoin node behind tor.  7:12 - 8:19 Discussing how Bitcoin node gossip addresses.  8:56 - 10:40 Explaining how DNS works  12:30 - 13:30: DNS is storing list of bitcoin nodes.  Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Follow Ruben Somsen @SomsenRuben Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

In this episode of The Van Wirdum Sjorsnado, Ruben Somsen returns to explain his proposal to combine blind merged mining and perpetual one-way pegs in order to create a new type of sidechain. The bad news: it won't make you rich but it could help scale Bitcoin! Helpful Links: https://medium.com/@RubenSomsen/21-million-bitcoins-to-rule-all-sidechains-the-perpetual-one-way-peg-96cb2f8ac302 Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Follow Ruben Somsen @SomsenRuben Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

In this episode Sjors and Aaron discuss Jose Femenias' Easypaysy proposal, an account system for Bitcoin, on Bitcoin. They also announce groundbreaking news: The Van Wirdum Sjorsnado now has its own RSS-feed! Aaron's article covering Easypaysy on Bitcoin Magazine https://bitcoinmagazine.com/articles/bitcoin-need-accounts-one-developer-thinks-figured The BIP in Github https://github.com/bitcoin/bips/blob/master/bip-0047.mediawiki Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost   Music! Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio

Sjors and Aaron discuss Signet, a new type of testnet for Bitcoin that was merged into Bitcoin Core last week. They also discuss the original version of testnet and its problems, as well as alternative testing environment regtest. Support the Show! Follow Bitcoin Magazine on Twitter @BitcoinMagazine Follow Aaron van Wirdum @AaronvanW Follow Sjors Provoost @provoost Music: Song Title: Segwit Sounds By: The NakamoTones Album: Citadel Music Produced by: Bitcoin Audio