Lightning Network

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Lightning Network Protocol Suite Lightning Network Protocol Suite.png
Lightning Network Protocol Suite
Example ACFKLQ routing through an idealized mesh network of payment channels. 17 node mesh network.svg
Example ACFKLQ routing through an idealized mesh network of payment channels.

The Lightning Network (LN) is a "layer 2" payment protocol built on the Bitcoin blockchain and those of other cryptocurrencies. [1] It is intended to enable fast transactions among participating nodes (independently run members of the network) and has been proposed as a solution to the bitcoin scalability problem. [2] [3] It is a peer-to-peer system for making micropayments of cryptocurrency through a network of bidirectional payment channels, without delegating custody of funds. [4]

Contents

Transacting parties use the Lightning Network by opening a payment channel and transferring (committing) funds to the relevant layer-1 blockchain (e.g. Bitcoin) under a smart contract. The parties then make any number of off-chain Lightning Network transactions that update the tentative distribution of the channel's funds, without broadcasting to the blockchain. Whenever the parties have finished their transaction session, they close the payment channel, and the smart contract distributes the committed funds according to the transaction record. [5]

To initiate closing, one node first broadcasts the current state of the transaction record to the network, including a proposed settlement, a distribution of the committed funds. If both parties confirm the proposal, the funds are immediately paid on-chain. The other option is uncooperative closure, for example if one node has dropped from the network, or if it is broadcasting an incorrect (possibly fraudulent) transaction state. In this case settlement is delayed during a dispute period, when nodes may contest the proposal. If the second node broadcasts a more up-to-date timestamped distribution, including some transactions omitted by the first proposal, then all committed funds are transferred to the second node: this punitive breach remedy transaction thwarts attempts to defraud the other node by broadcasting out-of-date transactions.

The Lightning network has received praise for having the "potential to transform the world of payments, making Bitcoin more accessible, faster, and cheaper to use" and is the scaling solution that can bring Bitcoin to the average person. [6] Lightning has been adopted by El Salvador to assist in adopting Bitcoin as a form of legal tender. [6] Lightning was also used by Robert F. Kennedy Jr.'s presidential campaign, making it the first time Bitcoin was used to fund a presidential campaign. [7] [8]

History

The network at birth, screenshot Recksplorer, February 5, 2018 LN Network 20180205.jpg
The network at birth, screenshot Recksplorer, February 5, 2018

Joseph Poon and Thaddeus Dryja published a Lightning Network white paper in February 2015. [9] [ non-primary source needed ]

2019 Bitcoin Lightning Torch

On January 19, 2019, pseudonymous Twitter user hodlonaut began a game-like promotional test of the Lightning Network by sending 100,000 satoshis (0.001 bitcoin) to a trusted recipient where each recipient added 10,000 satoshis ($0.34 at the time) to send to the next trusted recipient. The "lightning torch" payment reached notable personalities including Twitter CEO Jack Dorsey, Litecoin Creator Charlie Lee, Lightning Labs CEO Elizabeth Stark, and Binance CEO "CZ" Changpeng Zhao, among others. [10] [11]

Design

A Lightning Network overview

Andreas Antonopoulos calls the Lightning Network a second layer routing network. [12] The payment channels allow participants to transfer money to each other without having to make all their transactions public on the blockchain. [13] [14] This is secured by penalizing uncooperative participants. When opening a channel, participants must commit an amount on the blockchain (a funding transaction). [15] Time-based script extensions like CheckSequenceVerify and CheckLockTimeVerify make the penalties possible.

Implementations

Lightning operates under the BOLT (Basis of Lightning Technology) standard specification. [16] Its four major implementations are: Lightning Network Daemon, CoreLightning, Eclair, and Lightning Dev Kit. [17]

Benefits

The Lightning Network claims to provide several advantages over on-chain transactions:

Limitations

The Lightning Network is made up of bidirectional payment channels between two nodes which combined create smart contracts. If at any time either party drops the channel, the channel will close and be settled on the blockchain. [19] The on-chain transactions required to open and close lightning channels limit the scaleability of the lightning network. This can be mitigated if multiple users that trust each other share a lightning node. [20] Poon Dryja channels are typically used for smaller amounts because they require that keys be online. Secure operation of a high volume lightning node requires security mechanisms like a validating lightning signer or frequent swaps with cold storage. [21]

Lightning Network's dispute mechanism requires all users to watch the blockchain constantly for fraud. This vigilance can be outsourced to watchtower nodes, trusted providers who are paid to monitor for fraud.

A period of 24 hours is allotted to create a bidirectional channel after receiving a request.

Routing

In the event that a bi-directional payment channel is no longer open between the transacting parties, the payment must be routed through network intermediaries via an onion routing technique similar to Tor. This requires that the sender and receiver of the payment have open channels with enough established peer nodes to find a path for the payment. [22]

The original whitepaper on routing suggests that "eventually, with optimizations, the network will look a lot like Tier-1 ISPs".

Use cases

Laszlo Hanyecz, famous for paying 10,000 BTC for two pizzas in 2010, bought two more pizzas in 2018 via Lightning Network for 0.00649 BTC. [23] In 2021, Lightning was adopted by El Salvador to assist in adopting Bitcoin as a form of legal tender. [24] In 2023, Lightning was also used by Robert F. Kennedy Jr.'s presidential campaign, making it the first time Bitcoin was used to fund a presidential campaign. [25]

Lightning Internetwork

The lightning network based on Poon Dryja payment channels is interoperable with other payment networks that support HTLCs which results in a multi-asset network of networks. [26]

Related Research Articles

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<span class="mw-page-title-main">Cryptocurrency</span> Digital currency not reliant on a central authority

A cryptocurrency, crypto-currency, or crypto is a digital currency designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank, to uphold or maintain it.

Litecoin is a decentralized peer-to-peer cryptocurrency and open-source software project released under the MIT/X11 license. Inspired by Bitcoin, Litecoin was among the earliest altcoins, starting in October 2011. In technical details, the Litecoin main chain shares a slightly modified Bitcoin codebase. The practical effects of those codebase differences are lower transaction fees, faster transaction confirmations, and faster mining difficulty retargeting. Due to its underlying similarities to Bitcoin, Litecoin has historically been referred to as the "silver to Bitcoin's gold." In 2022, Litecoin added optional privacy features via soft fork through the MWEB upgrade.

<span class="mw-page-title-main">Bitcoin protocol</span> Rules that govern the functioning of Bitcoin

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Blockchain.com is a cryptocurrency financial services company. The company began as the first Bitcoin blockchain explorer in 2011 and later created a cryptocurrency wallet that accounted for 28% of bitcoin transactions between 2012 and 2020. It also operates a cryptocurrency exchange and provides institutional markets lending business and data, charts, and analytics.

<span class="mw-page-title-main">Ethereum</span> Open-source blockchain computing platform

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<span class="mw-page-title-main">Dash (cryptocurrency)</span> Cryptocurrency

Dash is an open source cryptocurrency. It is an altcoin that was forked from the Bitcoin protocol. It is also a decentralized autonomous organization (DAO) run by a subset of its users, which are called "masternodes".

<span class="mw-page-title-main">Bitcoin Core</span> Bitcoin node and wallet software

Bitcoin Core is free and open-source software that serves as a bitcoin node and provides a bitcoin wallet which fully verifies payments. It is considered to be bitcoin's reference implementation. Initially, the software was published by Satoshi Nakamoto under the name "Bitcoin", and later renamed to "Bitcoin Core" to distinguish it from the network. It is also known as the Satoshi client. Bitcoin Core includes a transaction verification engine and connects to the Bitcoin network as a full node.

A blockchain is a distributed ledger with growing lists of records (blocks) that are securely linked together via cryptographic hashes. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data. Since each block contains information about the previous block, they effectively form a chain, with each additional block linking to the ones before it. Consequently, blockchain transactions are irreversible in that, once they are recorded, the data in any given block cannot be altered retroactively without altering all subsequent blocks.

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<span class="mw-page-title-main">Ethereum Classic</span> Blockchain computing platform

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Bitcoin Cash is a cryptocurrency that is a fork of Bitcoin. Bitcoin Cash is a spin-off or altcoin that was created in 2017.

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References

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  3. "MIT and Stanford Professors Are Designing a Cryptocurrency to Top Bitcoin: Unit-e". fortune.com. January 17, 2019. Retrieved 2019-12-12.
  4. Popper, Nathaniel (August 15, 2017). "Bitcoin price surges after deal on software updates". The Boston Globe. Retrieved December 12, 2019.
  5. Lee, Timothy B. (2018-02-04). "Bitcoin has a huge scaling problem—Lightning could be the solution". Ars Technica. Retrieved 2019-12-12.
  6. 1 2 Fox, Martell. "Bitcoin's Lightning Network: What It Is And How It Works". Forbes. Retrieved 2024-03-13.
  7. "Bitcoin Miami: 2024 Candidates Robert F. Kennedy Jr and Gabbard Defend Bitcoin and Decentralization". Yahoo Finance. 2023-05-22. Retrieved 2024-03-13.
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  10. Browne, Ryan (6 February 2019). "Jack Dorsey says the 'only' cryptocurrency he owns is bitcoin". CNBC. Retrieved 17 December 2019.
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  12. 1 2 3 4 5 Antonopoulos, Andreas (2017-07-21). Mastering Bitcoin (2nd ed.). O'Reilly. pp. 297–304. ISBN   978-1491954386.
  13. "The Lightning Network Could Make Bitcoin Faster—and Cheaper". Wired. ISSN   1059-1028 . Retrieved 2019-12-12.
  14. "MIT, Stanford Academics Design Cryptocurrency to Better Bitcoin". Bloomberg. Retrieved 2019-12-12.
  15. Burchert, Conrad; Decker, Christian; Wattenhofer, Roger (August 29, 2018). "Scalable Funding of Bitcoin Micropayment Channel Networks" (PDF). Royal Society Open Science. 5 (8): 180089. Bibcode:2018RSOS....580089B. doi:10.1098/rsos.180089. PMC   6124062 . PMID   30225004 . Retrieved 17 December 2019.
  16. Lightning Network In-Progress Specifications, Lightning Network, 2022-10-15, retrieved 2022-10-15
  17. Perez, Sarah (2022-01-18). "Block's Cash App adopts Lightning Network for free bitcoin payments". TechCrunch. Retrieved 2022-10-15.
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  19. Antonopoulos, Andreas; Osuntokun, Olaoluwa; Pickhardt, René (January 4, 2022). "How the Lightning Network Works". Mastering the Lightning Network: A Second Layer Blockchain Protocol for Instant Bitcoin Payments (1st ed.). O'Reilly Media. ISBN   978-1492054863.
  20. Sztorc, Paul (April 4, 2022). "Lightning Network -- Fundamental Limitations". Truthcoin. Retrieved 2024-01-17.
  21. Kohler, Che (July 6, 2023). "What Is The Validating Lightning Signer?". The Bitcoin Manual. Retrieved 2024-01-18.
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  25. Toppa, Sabrina (2023-05-21). "Watch Robert F. Kennedy Jr.'s Keynote Address at Bitcoin 2023". TheStreet Crypto: Bitcoin and cryptocurrency news, advice, analysis and more. Retrieved 2024-03-28.
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