Trust-minimized optimistic cross-rollup arbitrary message bridge

Abstract

With the increasing acceptance and utilization of blockchain technology, a multitude of blockchain-based systems have emerged. Consequently, the need for interoperability among these systems has become paramount, particularly in a trustless manner. To enable decentralized and secure cross-chain applications for users, the establishment of a trust-minimized interoperability solution is imperative for homogeneous blockchain-based networks. This paper presents an analysis of the current state and challenges associated with interoperability between blockchain-based systems. Building upon previous research, we propose that the set of blockchain-based networks should be narrowed down based on the same settlement layer for supporting trust-minimized interoperability. Specifically, we concentrate on the cross-rollup functionality between rollups. We have devised and implemented two similar solutions to address the aforementioned interoperability problem, employing a trust-minimized optimistic approach. Through extensive experimentation, we compare our proposed solutions with existing cross-rollup bridges in terms of gas consumption, time complexity, and newly introduced trust assumptions. Our experimental investigations concentrate on the transmission of arbitrary data utilizing non-fungible tokens. The results reveal that one of our proposed solutions offers an optimal approach for cross-rollup communication between optimistic rollups.