did - a udid network top level name

Unified Decentralized Identity (UDID) Naming is a secure naming and verifiable protocol, UDID names provide a way for users to cross-network and customizable top-level names, run self-priced sub-name resources for branding, and Human-readable names map to Web3 and Web2 resources, such as blockchain addresses, hashes, IoT devices, or URLs. UDID can be traded on the secondary market based on the ERC721 standard.