{"id":37708,"date":"2022-08-17T15:26:00","date_gmt":"2022-08-17T12:26:00","guid":{"rendered":"https:\/\/forklog.com\/en\/?p=37708"},"modified":"2025-08-29T20:19:47","modified_gmt":"2025-08-29T17:19:47","slug":"what-is-a-layer%e2%80%912-solution-in-blockchain","status":"publish","type":"post","link":"https:\/\/u1f987.com\/en\/what-is-a-layer%e2%80%912-solution-in-blockchain\/","title":{"rendered":"What is a layer\u20112 solution in blockchain?"},"content":{"rendered":"<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">Key points<\/h2>\n<ul class=\"wp-block-list\">\n<li>A layer\u20112 (L2) solution is a protocol built atop a base blockchain (layer 1) to improve scalability.<\/li>\n<li>L2s are used with popular but throughput\u2011constrained platforms such as Ethereum and Bitcoin.<\/li>\n<li>An L2 is tightly integrated with the base network, with compatible smart contracts and cryptoassets.<\/li>\n<li>On Ethereum, moving funds between the mainnet and an L2 requires a cross\u2011chain bridge.<\/li>\n<\/ul>\n<\/div>\n<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">Why do layer\u20112 solutions matter?<\/h2>\n<p>Blockchains face the \u201cscalability trilemma\u201d: it is hard to build a network that is simultaneously fast, decentralised and secure. Developers often optimise at most two of the three.<\/p>\n<p>Early architectures\u2014most notably Bitcoin and Ethereum\u2014were not designed for high volumes of users and transactions, leaving them with low throughput. Bitcoin processes roughly 5\u20137 transactions per second (TPS); Ethereum about 15 TPS.<\/p>\n<p>Scalability can be improved by changing the base protocol\u2014eg via sharding\u2014but such upgrades take time, can span years and alter core architecture, so communities do not always agree to them.<\/p>\n<p>L2s address low throughput and high fees without touching the base chain\u2019s code. Their chief virtue is enabling transfers between layer\u20111 addresses while using a \u201csecond layer\u201d, which can be an off\u2011chain protocol or a separate blockchain.<\/p>\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\">\n<div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"\u0427\u0442\u043e \u0442\u0430\u043a\u043e\u0435 \u0440\u0435\u0448\u0435\u043d\u0438\u0435 \u0432\u0442\u043e\u0440\u043e\u0433\u043e \u0443\u0440\u043e\u0432\u043d\u044f (Layer 2)?\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/lOSA1xyJd-I?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><figcaption>Watch ForkLog\u2019s explainer on layer\u20112 solutions in blockchain.<\/figcaption><\/figure>\n<\/div>\n<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">Which layer\u20112s exist for Bitcoin?<\/h2>\n<p>The main L2 for the first cryptocurrency is the Lightning Network (LN). It operates via smart contracts and so\u2011called state channels. Launched in 2015, it has continued to develop; by late May 2022 total channel capacity reached 3,900 BTC.\u00a0<\/p>\n<p>LN\u2019s core function is to let bitcoin holders transact directly without recording every transfer on the base chain. Users open a special channel via a single on\u2011chain transaction and deposit BTC into it.\u00a0<\/p>\n<p>Once active, the payment channel enables off\u2011chain transfers\u2014outside the base network\u2014at far higher speeds and lower fees. Unlike on\u2011chain transactions, operations within Lightning channels are visible only to the participants. Only the initial and final states are written to the main blockchain.\u00a0<\/p>\n<p>This approach sharply reduces load on Bitcoin\u2019s base layer: Lightning can process thousands of operations per second while maintaining a high level of security.<\/p>\n<\/div>\n<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">How are Lightning Network payment channels secured?<\/h2>\n<p>Channels are verified by their participants via mutual smart contracts. When off\u2011chain exchanges conclude, the final state is recorded in a new block on the base chain. Smart contracts safeguard transactions within state channels and act as \u201cjudges\u201d between participants.\u00a0<\/p>\n<p>Some channels use a timer that automatically updates or locks the on\u2011chain state. When the set period expires, the system triggers a final transaction, updates the base blockchain and closes the state channel using the last verified transaction. Any new attempt to unlock the channel generates new cryptographic data and restarts the timer.<\/p>\n<\/div>\n<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">Which layer\u20112s exist for Ethereum?<\/h2>\n<p>Despite modest speed, Ethereum is the busiest platform for decentralised applications. Many leading projects in decentralised finance (DeFi) and non\u2011fungible tokens (NFTs) run on it, making scalability a pressing issue.<\/p>\n<p>Several major L2s are developing in parallel:<\/p>\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-polygon-matic\">Polygon<\/a> (MATIC);<\/li>\n<li><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-arbitrum\">Arbitrum<\/a>;<\/li>\n<li><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-optimism-op\">Optimism<\/a>.<\/li>\n<\/ul>\n<p>The core enabling technology is Rollups, in two main flavours:<\/p>\n<ol class=\"wp-block-list\">\n<li>Optimistic Rollups. Transactions execute on the L2, then are bundled into compact batches and submitted by validators to the Ethereum mainnet. Optimistic Rollups power Arbitrum and Optimism.<\/li>\n<li>ZK\u2011Rollups. Transactions on the second layer are also batched and posted to Ethereum, but they are confirmed using special verifiers that provide cryptographic proofs of validity. Polygon is built on ZK\u2011Rollups. Ethereum co\u2011founder Vitalik Buterin views this as the primary scaling technology for Ethereum.<\/li>\n<\/ol>\n<p>Whatever the L2, Ethereum as the \u201cfirst layer\u201d handles transaction verification and block production, maintains the ledger of final states and provides the consensus mechanism. Projects therefore need not build their own infrastructure.<\/p>\n<p>There are other L2 projects. For example, in July 2022 the startup Matter Labs <a href=\"https:\/\/forklog.news\/razrabotchiki-zksync-anonsirovali-zapusk-resheniya-v-osnovnoj-seti-ethereum\/\" target=\"_blank\" rel=\"noreferrer noopener\">an<\/a><a href=\"https:\/\/forklog.news\/razrabotchiki-zksync-anonsirovali-zapusk-resheniya-v-osnovnoj-seti-ethereum\/\">nounced<\/a> the launch of zkSync 2.0. A month later, the StarkWare project launched its own protocol written in Cairo.<\/p>\n<\/div>\n<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">How do you move assets from layer 1 to layer 2?<\/h2>\n<p>To transfer cryptocurrencies from a layer\u20111 blockchain to an L2 network, use cross\u2011chain bridges.\u00a0\u00a0<\/p>\n<p>You will need a browser\u2011based Web3 wallet such as MetaMask or WalletConnect. Add the desired network in the wallet settings\u2014for example, Optimism.<\/p>\n<p>The project offers an <a href=\"https:\/\/app.optimism.io\/bridge\" target=\"_blank\" rel=\"noreferrer noopener\">official bridge<\/a>. On the bridge site, choose the asset to transfer, enter the amount, confirm the transaction and receive the same tokens on the L2. There are also native bridges for <a href=\"https:\/\/wallet.polygon.technology\/login?next=%2Fbridge%2F\" target=\"_blank\" rel=\"noreferrer noopener\">Polygon<\/a> and <a href=\"https:\/\/bridge.arbitrum.io\" target=\"_blank\" rel=\"noreferrer noopener\">Arbitrum<\/a>.<\/p>\n<p>L2 tokens can be used much like \u201coriginals\u201d\u2014for transfers, trading on decentralised exchanges or in DeFi protocols. Most major applications support L2 assets. Uniswap has <a href=\"https:\/\/uniswap.org\/blog\/multichain-uniswap\" target=\"_blank\" rel=\"noreferrer noopener\">called<\/a> this approach \u201cmultichain\u201d.<\/p>\n<\/div>\n<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">Are sidechains layer\u20112 solutions?<\/h2>\n<p>Sidechains used in ecosystems such as Cosmos or Polkadot are not L2s. The former use their own security, whereas the latter rely on a parent blockchain.<\/p>\n<\/div>\n<div class=\"wp-block-text-wrappers-cards single_card\">\n<h2 class=\"card_label\">Further reading<\/h2>\n<p><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-web3\">What is Web3?<\/a><\/p>\n<p><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-a-bitcoin-improvement-proposal-bip\">What is a Bitcoin Improvement Proposal (BIP)?<\/a><\/p>\n<p><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-a-merkle-tree\">What is a Merkle tree?<\/a><\/p>\n<p><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-staking-and-how-to-make-money-from-it\">What is staking and how can you earn from it?<\/a><\/p>\n<p><a href=\"https:\/\/u1f987.com\/en\/news\/what-is-a-hard-fork\">What is a hard fork?<\/a><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>What are layer\u20112 (L2) solutions? How do they help scale Ethereum and Bitcoin? How do you move assets between layer 1 and layer 2, and back? Explained in cards.<\/p>\n","protected":false},"author":1,"featured_media":37709,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"select":"1","news_style_id":"1","cryptorium_level":"1","_short_excerpt_text":"","creation_source":"","_metatest_mainpost_news_update":false,"footnotes":""},"categories":[2113],"tags":[2117,2115,46,1179,325,277],"class_list":["post-37708","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cryptorium","tag-101-altcoins","tag-101-technical-foundations","tag-ethereum","tag-layer-2-solutions","tag-lightning-network","tag-scaling"],"aioseo_notices":[],"amp_enabled":true,"views":"182","promo_type":"1","layout_type":"1","short_excerpt":"","is_update":"","_links":{"self":[{"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/posts\/37708","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/comments?post=37708"}],"version-history":[{"count":1,"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/posts\/37708\/revisions"}],"predecessor-version":[{"id":37710,"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/posts\/37708\/revisions\/37710"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/media\/37709"}],"wp:attachment":[{"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/media?parent=37708"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/categories?post=37708"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/u1f987.com\/en\/wp-json\/wp\/v2\/tags?post=37708"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}