Ethereum Name Service (ENS) is an open-source, distributed, and extensible naming system built on the Ethereum blockchain. It aims to make Ethereum-based web more accessible and understandable for humans, much like how the Internet’s Domain Name Service (DNS) simplifies internet navigation. ENS transforms human-readable Ethereum addresses into machine-readable alphanumeric codes, and vice versa. This functionality allows users to replace long, complex Ethereum addresses with simple, memorable ones, enhancing user experience and facilitating wider adoption of blockchain technologies. ENS is not a company but an open-source project that seeks to become a vital piece of infrastructure for Web3, similar to how DNS is integral to the internet.

ENS operates on two primary smart contracts. The first is the ENS registry, which records domains registered on ENS and stores information about each of them, including the domain owner and the domain resolver. The second smart contract is the resolver, which translates machine-readable addresses to domain names and vice versa. This contract also matches each domain to its corresponding user, website, or address. ENS uses a system of dot-separated hierarchical names called domains, with domain owners having full control over their subdomains. This system is similar to the one used by DNS, making it familiar and easy to use for most internet users.

ENS aims to simplify the user experience in the blockchain space by replacing machine-readable alphanumeric codes with short, easy-to-remember links. This functionality can be used to receive any cryptocurrency, token, or non-fungible token (NFT) to a simple link, aiming to make blockchain technology less technical and more accessible. ENS also supports 'reverse resolution', enabling the association of metadata such as canonical names or interface descriptions with Ethereum addresses. Furthermore, ENS can be used to launch censorship-resistant decentralized websites. Users can upload their website to the InterPlanetary File System (IPFS) and access it with their ENS name, enhancing the decentralization and security of web content.

ENS was initially a part of the Ethereum Foundation, but it spun off as a separate organization in 2018. Its Lead Developer is Nick Johnson, a software engineer from New Zealand who previously worked at Google and the Ethereum Foundation. ENS had a retroactive airdrop in November 2021 that rewarded users who had registered addresses before the project launched its token. ENS continues to work towards its goal of making the Ethereum-based web easier to access and comprehend for humans.

The Ethereum Name Service (ENS) strives to make blockchain addresses more user-friendly by mapping human-readable names like 'alice.eth' to machine-readable identifiers such as Ethereum addresses, other cryptocurrency addresses, content hashes, and metadata. This system is akin to the Internet's Domain Name Service (DNS), but it operates with a distinct architecture due to the capabilities and constraints provided by the Ethereum blockchain. ENS operates on a system of dot-separated hierarchical names called domains, with the owner of a domain having full control over subdomains. This hierarchical nature of ENS allows anyone who owns a domain at any level to configure subdomains as desired. For instance, if Alice owns 'alice.eth', she can create 'pay.alice.eth' and configure it as she wishes. This user-friendly approach of ENS aims to improve user experience and accessibility within the Ethereum network.

The Ethereum Name Service (ENS) permits users to register domain names that are easier to use compared to conventional blockchain addresses. The native name suffix for ENS is .ETH, which aims to provide the full security benefits of being blockchain-native. ENS also accommodates most DNS names, including .com, .org, .io, .app, .xyz, and .art. This means that users can link their existing DNS domains to ENS, establishing a connection between the traditional internet and the decentralized web. ENS also supports names that exist outside the blockchain via CCIP read, enabling users to import their DNS domains, distribute subnames, store records, and more.

Registering and managing domain names on Ethereum Name Service (ENS) is a process that involves several steps. To register a domain, you first need to visit the ENS app and search for the desired domain name. If the name is available, you should be able to select the duration for which you want to register the name and proceed to request registration. This process involves a transaction on the Ethereum blockchain, so you'll need to have enough ETH in your wallet to cover the registration costs and gas expenses. Once the transaction is confirmed, you should be able to finalize the registration after waiting for a minute. Managing your ENS domain involves setting a resolver and updating records. A resolver is a smart contract that provides the logic for looking up your resources, and it must be set for each domain. You should be able to update records such as the address, content, and other details associated with your domain. You should also be able to create subdomains and transfer ownership of your domains. Remember, all these actions are transactions on the Ethereum blockchain and will require gas expenses.

The Ethereum Name Service (ENS) manages updates or changes to domain records, including IP addresses, through a decentralized protocol and ABI definition. This protocol provides a mechanism for resolution of short, human-readable names to service and resource identifiers. When the underlying resource changes, such as a contract, content-addressed data, or an IP address, the ENS provides a mechanism for these names to be updated as necessary. This is facilitated through a system of registries and resolvers. The registry is a single contract that provides a mapping from any registered name to the resolver responsible for it. Resolvers are responsible for performing resource lookups for a name, returning a contract address, a content hash, or IP address(es) as appropriate. The updating of domain records can be handled separately from resolution, providing a specified interface for updating domains.

The Ethereum Name Service (ENS) resolver has a role in the domain resolution process. It is a smart contract that translates human-readable names into machine-readable identifiers, such as Ethereum addresses, other cryptocurrency addresses, content hashes, and metadata. The ENS resolver operates by associating specific data types with names. For instance, it has the capability to store and resolve the addresses of any arbitrary blockchain. The process of resolving a name to an Ethereum address involves using various libraries. The ENS resolver also supports reverse resolution, mapping from an address back to a name. This feature allows applications to display ENS names instead of hexadecimal addresses, which may affect user experience. ENS does not enforce the accuracy of reverse records, indicating that users may need to perform a forward resolution for the returned name to verify it matches the original address.

The Ethereum Name Service (ENS) plays a role in the decentralization of websites and content hosted on the InterPlanetary File System (IPFS). ENS and IPFS work together to provide a decentralized method to host and serve websites. ENS, akin to a decentralized version of DNS (Domain Name System), allows for the assignment of human-readable names to complex Ethereum addresses or other blockchain resources. This facilitates user interaction with these resources, as they no longer need to remember long, complex addresses. When it comes to websites, ENS can link these human-readable domain names (ending in .eth) to IPFS hashes, which represent the content of a website. IPFS, on the other hand, is a peer-to-peer hypermedia protocol designed to enhance the web's efficiency, security, and openness. It decentralizes the hosting of files across various nodes operated by various individuals globally. When a user enters a .eth domain into their browser, it resolves to the corresponding website hosted on IPFS, with the intention of supporting the decentralization of websites and content.

The Ethereum Name Service (ENS) root is a component of the ENS architecture, functioning as the topmost level of the ENS hierarchy. It can be compared to the root directory in a computer's file system, serving as the starting point for all domain name resolutions. The ENS root is managed by a smart contract on the Ethereum blockchain, which allows for decentralized control and operation. This smart contract, known as the ENS root registrar, has the role of allocating and managing top-level domains (TLDs) like .eth. The ENS root fits into the overall architecture by providing a decentralized method for managing and resolving human-readable names in the Ethereum ecosystem. It is a part of the infrastructure that aims to offer improvements within the Ethereum space, by aiming to provide an alternative to long, complex Ethereum addresses.

The Ethereum Name Service (ENS) supports subdomains in a hierarchical structure that is similar to the traditional Domain Name System (DNS). If you control a .eth domain, you have the ability to deploy smart contracts that enable users to establish their own subdomains. This is accomplished by invoking the setSubnodeOwner function on the ENS registry smart contract. Once this process is successful, the controller of the domain or subdomain can set the resolver and the target address. This hierarchical structure facilitates a structured organization and management of names on the ENS. For example, if you control the domain example.eth, you have the ability to configure subdomains such as test1.example.eth and test2.example.eth at your discretion. Each subdomain can be linked to different online sources, which aids in facilitating a structured approach to managing names on ENS.

The Ethereum Name Service (ENS) registry is a decentralized, open, and extensible naming system built on the Ethereum blockchain. It maps human-readable names like 'alice.eth' to machine-readable identifiers such as Ethereum addresses, content hashes, and metadata. The ENS registry keeps a record of domains and subdomains, storing three critical pieces of information about each: the owner of the domain, the resolver for the domain, and the caching time-to-live for all records under the domain. The owner of a domain can be an external account (a user) or a smart contract. A registrar is a smart contract that owns a domain and issues subdomains of that domain to users who adhere to the rules defined in the contract. The ENS registry upholds the ownership of domain names through mechanisms such as enabling domain owners to set the resolver and TTL for the domain, facilitating the transfer of domain ownership to another address, or permitting the change in ownership of subdomains.

Ethereum Name Service (ENS) handles the renewal and expiration of registered domain names in a user-friendly manner. When a user registers a domain name with ENS, they select the duration of their registration. This duration can be extended at any time by fulfilling the required conditions, with no maximum limit on the renewal duration. However, there is a minimum renewal period of 28 days. If a user does not renew their domain name before it expires, ENS provides a 'grace period' of 90 days. During this period, the user can still renew their domain name to retain ownership. If the domain name is not renewed within the grace period, it becomes available for registration by others. The conditions for yearly renewals may vary depending on the length of the domain name. It's important to note that conditions for renewal are not reversible. ENS intends to facilitate the process of managing digital identities on the blockchain.