# KUB Layer 2 Network ## **Introduction to Layer 2 Networks** Blockchain technology, in its foundational form (known as a Layer 1 network), faces a well-known challenge: the **blockchain trilemma**. This concept states that a blockchain can only effectively achieve two of the three key properties: **scalability**, **security**, and **decentralization**. A Layer 1 network like KUB, or others like Ethereum, prioritizes security and decentralization, but this can lead to limitations in transaction speed and higher fees when network usage is high. A Layer 2 network is a secondary framework or protocol built on top of a Layer 1 blockchain. Its primary purpose is to address the scalability issue by handling a large number of transactions off the main chain, thereby increasing the network's throughput and reducing transaction costs. ## **The Rollup Approach** The KUB Layer 2 network, like many modern L2 solutions, utilizes a technology called a rollup. Rollups bundle hundreds of transactions into a single, compressed transaction that is then submitted to the main Layer 1 network. This significantly reduces the amount of data that needs to be processed on the main chain, leading to faster and cheaper transactions. There are two main types of rollups: * Optimistic Rollups: This model operates under the assumption that all transactions bundled in a rollup are valid. It only verifies the transactions if a fraud proof is submitted by a user who suspects fraudulent activity. This optimistic approach allows for very high transaction speeds. A challenge period is a key feature, giving users a window of time to submit a fraud-proof. * Zero-Knowledge (ZK) Rollups: These rollups use complex cryptographic proofs (known as ZK-proofs) to instantly verify the validity of off-chain transactions. A small proof is submitted to the Layer 1 network, which cryptographically guarantees that all transactions in the bundle are valid. This provides near-instant finality without a challenge period. ## KUB Layer 2 Network The KUB Layer 2 network is an extension of the main KUB network (Layer 1). It is designed to enhance the KUB network's performance by providing a low-cost, high-speed environment for decentralized applications (dApps) and user transactions. ### Connecting to the KUB Layer 2 Network Connecting to the KUB Layer 2 network is a straightforward process, similar to connecting to other blockchain networks. You will need a compatible cryptocurrency wallet, such as [MetaMask](https://metamask.io/). You can follow the instructions in this [guide](/about-kub/connect-to-kub.md) or enter the following RPC details: {% tabs %} {% tab title="Layer 2 Mainnet" %} | Name | Value | | ------------------ | ------------------------------- | | Network Name | KUB Layer 2 Mainnet | | RPC URL | | | Chain ID | 9601 | | Currency Symbol | KUB | | Block Explorer URL | | | {% endtab %} | | {% tab title="Layer 2 Testnet" %} | Name | Value | | ------------------ | --------------------------------------- | | Network Name | KUB Layer 2 Testnet | | RPC URL | | | Chain ID | 259251 | | Currency Symbol | tKUB | | Block Explorer URL | | | {% endtab %} | | | {% endtabs %} | | ### Obtaining tKUB on the KUB Layer 2 Testnet For developers wishing to develop their decentralized applications (dApps) on the KUB Layer 2 Testnet, you will need some tKUB. To obtain tKUB on the KUB Layer 2 Testnet, you first need to acquire tKUB on the KUB Testnet. Follow this [guide](/tools/testnet-faucet.md) or visit the [KUB Faucet](https://faucet.kubchain.com/) to obtain some tKUB. Once you have received your tKUB, navigate to the section labeled **Bridge to KUB Layer 2 Testnet**. You will be presented with options to select the amount of tKUB you want to transfer from the KUB Testnet to the KUB Layer 2 Testnet. After making your selection, follow the on-screen instructions to complete the bridging process. {% hint style="info" %} You'll be able to receive 5 tKUB every 24 hours using the KUB Faucet. {% endhint %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.kubchain.com/build-on-kub/kub-layer-2-network.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.