What Is Ethereum Name Service?

Ethereum Name Service is a decentralized and extensible naming system based on the Ethereum blockchain. ENS is deployed to convert human-readable names like “alice.eth” to a machine-readable identifier format such as Ethereum addresses, content hashes, metadata, and other cryptocurrency addresses. In addition, ENS supports the reverse resolution, which makes it possible to associate metadata such as interface descriptions or canonical names with Ethereum addresses.

ENS has goals similar to DNS, the internet’s Domain Name System. But the architecture differs significantly due to the capabilities and constraints provided by the Ethereum blockchain. Like DNS, ENS works on a system of dot-separated hierarchical names called domains (for example, .com and .org). Here, the owner of a domain has complete control over subdomains.

The architecture of ENS has two principal components: the registry and resolvers. The ENS registry uses a single smart contract to maintain a list of all domains and subdomains and stores critical information associated with it, i.e., owner of the domain, resolver of the domain, and caching time-to-live for all records under the domain. In brief, smart contracts are just like regular contracts; however, instead of being drafted on paper, these contracts run in the form of protocols on blockchain. Moreover, these (ENS registry) smart contracts own the top-level domains (like .eth and .test) and specify the rules governing their subdomains' allocation. 

By following the rules set by these registrar contracts, anyone can get ownership of a domain for their use. ENS also allows users to import names that are already owned in DNS for use on ENS. Notably, the domain owner may be an external account (a user) or a smart contract. But a registrar is a smart contract that owns a domain and issues subdomains to users following some set of rules as determined in the contract. The .eth registrar migrated and became an ERC721-compliant non-fungible token (NFT) contract, which means .eth registrations can be transferred similar to those of other NFTs.

Moving to the next component, resolvers are actually involved in the process of translating names into addresses. Any contract that executes the relevant standards can act as a resolver in ENS. 

To summarize, one can easily understand ENS by simply comparing it with DNS. DNS converts website address domain names into Internet Protocol (IP) addresses. ENS also serves the same purpose, but domains are mapped into 42-character Ethereum addresses instead of IP addresses.

The hierarchical structure of ENS enables anyone who owns a domain at any level to configure subdomains for themselves or others as desired. For instance, if X owns alice.eth, they can create pay.alice.eth and configure it as per their wish.

About the governance, the ENS DAO (decentralized autonomous organization) is a DAO that governs the ENS protocol. The Ethereum Name Service token with ticker ENS is the standard ERC20 governance token of the ecosystem. Three governance forums have been created to govern the ecosystem depending on the need. The first one is Venues, discuss.ens.domains, a Discourse forum for governance-related discussion. The second one is Snapshot, a simple voting interface that lets users signal sentiment off-chain. The third one is Governance Portals. Tally is a governance portal that authorizes token holders to delegate their votes and allows delegates to create and vote on binding proposals. Sybil is another such governance portal. 

History of Ethereum Name Service

ENS was started at the Ethereum Foundation in early 2017. Later, ENS spun off with a separate organization in 2018. ENS development is driven by the Singaporean nonprofit True Names Ltd.

Nick Johnson is the founder as well as the lead developer of ENS. He also served as a software engineer in several companies like Ethereum, Google, Lumi, spider.io, smart sparrow, Telogis, Haydrian corporation, and Niche Software Ltd.Johnson is a computer science graduate from the University of Canterbury.