UMTP: A cross-metaverse virtual asset trading platform designed around self-sovereign identity

The rise of blockchain and the metaverse has promoted the arrival of Web 3. 0, a new era in which users can generate and trade valuable digital content like artworks and game items on decentralized platforms in the form of Non-fungible tokens (NFTs), and how to trade NFTs across different metaverses is receiving more and more attention. Existing third-party solutions compromise decentralization and anonymity, contradicting the core principles of Web 3. 0. To solve this challenge, we propose the Universal Metaverse Trading Platform (UMTP), a cross-metaverse virtual asset trading platform designed around Self-Sovereign Identity (SSI). Unlike traditional notary schemes that rely on centralized identity management, UMTP pioneers integrating SSI into notarization protocols to enable SSI-based anonymous credential–protected election, enabling committee members to operate using DIDs while maintaining accountability. In simulations, UMTP’s final cleanup rate is 13 percentage points higher than PageRank’s. Against the Long-History Prediction Attack and the Recent-Driven Prediction Attack, UMTP improved security by 63. 7\% and 64. 8\%. Second, some user-oriented secure trading functions are introduced to better meet the diversified needs of users; finally, the Identity Restoration System provides additional insurance for users’ virtual assets. We demonstrate the effectiveness and scalability of our proposed scheme through simulations.