The security of off-chain BTC is not uniform—counterparty risk increases in the following order: Lightning-Channel BTC → Ark BTC → Spark BTC → Liquid BTC → Cashu BTC → Custodial BTC. The Lightning Network is a channel layer plus a routing layer. If you run your own channel, the routing layer lets you settle payments directly. For the other five off-chain wallets, the operator shares its own Lightning channels with users, allowing them to send and receive Lightning payments. Liquid example • Paying — your wallet sends the same amount of L-BTC, and the operator pays the invoice through its channels. • Receiving — the operator first receives BTC over Lightning, then sends you the equivalent L-BTC. Liquid, Spark, and Ark can make users’ sending and receiving of Lightning payments atomic. Lightning is the transport network—other off-chain solutions plug in as special nodes.

Message relay + Media relay + Call relay (maybe)

Spark is to Statechains what Cashu is to Ecash. Just as there are different Cashu mints, can we also expect different Spark entities? View quoted note →

@Roy @Breez ⚡️ We really like Breez’s concept of “Bitcoin in Every App.” You’ve already released the native Lightning SDK and the Liquid + Lightning SDK, and you’re currently developing the Spark + Lightning SDK. Will you consider developing an Ark + Lightning SDK next? View quoted note →

Urbit is developing Tlon Messenger—a truly special peer-to-peer messenger, every bit as special as Urbit itself—on its personal server. “TM is built on a peer-to-peer network. Signing up for an account with TM gives you your own node and identity on this network. Think of a node as a cloud computer, yours to keep and customize. Think of your identity as a phone number, yours to keep even if you change carriers. On a peer-to-peer network, nodes connect directly to other nodes. When you send a message on TM, your computer sends it straight to your friend's computer. No middlemen. When you send a message on any other messaging platform, your message pings through the service's servers before it eventually makes its way to your intended recipient. Sometimes those messages get stored, often those messages get mined.” So in TM, a message first goes from the app on your phone to your own node; your node then sends it directly to the recipient’s node, and the recipient’s phone pulls the message from that node. 🤔

Frequently Asked Questions

Tlon exists to build exceptionally well-crafted software for people

For a user of Statechains, the counterparty risk he faces is that if the Statechains operators colludes with a previous owner of the funds, he will lose the funds he received. What is the maximum number of sats you would put into Statechains? View quoted note →

Spark is a variant of Statechains. Statechains are an original second-layer protocol originally developed by Ruben Somsen in 2018. Statechains are a proposed off-chain system that allows a user (such as Alice) to delegate the ability to spend a UTXO to another user (Bob), who can then further delegate the spending authority to a third user (Carol), and so on. The off-chain delegation operations are all performed using signature adaptors and the cooperation of a trusted third party who employs the eltoo mechanism—and their knowledge of every previous delegation—to ensure each new delegation uses a state number higher than any previously used state number. These incrementing state numbers ensure that an on-chain spend by the most recent delegate (Carol) can take precedence over spends by previous delegates (Alice and Bob), provided the trusted third party hasn’t colluded with a previous delegate to cheat. Beyond collusion with a delegated signer (such as Alice or Bob), there is no way for the trusted third party to steal funds. A delegated signer can always spend the UTXO on-chain without needing permission from the trusted third party, arguably making Statechains less trusted than federated sidechains. We can think of Statechains as a digital version of Opendime. We know that Statechains can’t provide the same trustless self-custody as the Lightning Network, but we still like them. Statechains can be part of the Lightning Network. https://medium.com/@RubenSomsen/statechains-non-custodial-off-chain-bitcoin-transfer-1ae4845a4a39

Bitcoin Optech

Statechains

Statechains are a proposed offchain system for allowing a user (such as Alice) to delegate the ability to spend a UTXO to another user (Bob), who c...

OPENDIME™ – World's First Bitcoin Credit Stick Wallet

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Bitcoin Magazine

Bitcoin Layer 2: Statechains

The second article in the Bitcoin Layer 2 series. This article covers Statechains, originally designed by Ruben Somsen, and implemented by Commerce...

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Spark: Bitcoin's Payment Layer for Stablecoins & Instant BTC

Build wallets, issue stablecoins, and move BTC instantly: all natively on Bitcoin. No bridges, no custodians. Start building with Spark's SDKs today.

View quoted note →

Wallet of Satoshi @Wallet of Satoshi just announced that its private beta now supports Spark, so the diagram below is now somewhat inaccurate. View quoted note →

Testing Sakura. View quoted note →

“But people can’t memorize public keys.” “But how many phone numbers can you memorize?” View quoted note →

WebTorrent - Streaming browser torrent client

WebTorrent, the streaming torrent client for the browser, Mac, Windows, and Linux

Perhaps building on top of WebTorrent would be the best fit. View quoted note →

If we imagine information technology as a skyscraper, AI adds the upper stories, while Bitcoin, Nostr, and Keychat strengthen its foundations. The extra height from AI is obvious to everyone, whereas the foundations lie out of sight and take longer for most people to appreciate. And the higher the tower rises, the stronger its foundations must be.

Keychat users can set the media relay to their own Blossom server, which corresponds to Blossom’s first use case mentioned in the note below. View quoted note →

BTC + Web

Good results 🌝 View quoted note →

Keychat Mini Game