Cross-Rollup Communication

Motivation

Rollups have gained significant attention and adoption for their ability to enhance blockchain scalability, reduce transaction costs, and improve overall efficiency. Lumoz provides ZK-RaaS services for Web3 applications, enabling developers to create their own Rollups through the Lumoz Rollup Launchbase. In this era of multiple Rollups, we anticipate a growing coexistence of various Rollups, making seamless interoperability between different Layer 2 solutions crucial.

Currently, interactions between Rollups remain relatively isolated, lacking real-time cross-chain communication and asset interoperability. This isolation has led to a fragmented landscape, where assets are confined within specific Rollups, restricting their free flow and utilization across different networks.

The absence of efficient cross Rollup communication not only limits the potential of individual Rollups but also impacts the overall user experience. Users attempting to transfer assets or execute cross-chain transactions between Rollups face cumbersome and time-consuming processes. This suboptimal experience weakens the appeal of Rollups and to some extent hinders the widespread adoption of Layer 2 scaling solutions.

Existing cross Rollup bridging solutions often involve deploying new sets of interchain contracts on Rollup chains and utilizing multi-chain liquidity incentives to achieve asset cross-chain functionality. However, these solutions are not universally applicable for message-based cross-chain interactions and come with risks of centralization and trust.

To fully unlock the potential of the multi Rollup era, there is an urgent need for a trustless and universal cross Rollup communication protocol.

Lumoz's Solution

In fact, each ZK-Rollup comes with an L1<>L2 bridge inherently, which we refer to as the Native bridge. Unlike third-party bridges that utilize liquidity-based schemes, the Native bridge operates as the unique "mint-burn" cross-chain mechanism. It ensures security through zero-knowledge proofs while maintaining trustlessness. All assets on a Rollup originate from deposit transactions through the native bridge and receive ultimate security endorsement from it.

We firmly believe in the principle of Occam's Razor – "Entities are not to be multiplied beyond necessity." Third-party bridges may offer cheaper and faster cross-chain experiences, but they introduce additional trust costs and security risks. The recent Multichain incident is a case in point. Therefore, from the outset, Lumoz's inspiration for cross-Rollup communication was elegantly straightforward: leverage the native bridge directly for achieving multi-Rollup interoperability, rather than introducing an additional third-party bridge. This concept gave birth to the NCRC (Native Cross Rollup Communication) protocol.