Abstract
Non-Fungible Tokens (NFTs) have created new and interesting ways to own digital assets. Our work defines non-fungible tokens as a pair and addresses challenges in cross-chain NFT transfers, particularly on interoperability between siloed blockchains. We develop a methodology and propose a Greed Factor to prioritize various hashing methods for detecting duplicates. Our practical approach marks an advancement over existing methods by using an analysis of over 400,000 real-world NFTs across 50 collections, which is easily applicable to existing bridges. The experimental results show the limitations of current implementations, and we offer insights to strengthen their functionality and foster the future growth of NFTs.