This report, published 18 March 2022, looks at the Delay Towers mechanism that was pioneered and deployed in the 0L Network.
The article was co-authored by Shashank Motepalli and Hans-Arno Jocobsen of the University of Toronoto. We quote the original synopsis below:
Growing excitement around permissionless blockchains is uncovering its latent scalability concerns. Permissioned blockchains offer high transactional throughput and low latencies while compromising decentralization. In the quest for a decentralized, scalable blockchain fabric, i.e., to offer the scalability of permissioned blockchain in a permissionless setting, we present L4L to encourage decentralization over the permissioned Libra network without compromising its sustainability. L4L employs delay towers, — puzzle towers that leverage verifiable delay functions — for establishing identity in a permissionless setting. Delay towers cannot be parallelized due to their sequential execution, making them an eco-friendly alternative. We also discuss methodologies to replace validators participating in consensus to promote compliant behavior. Our evaluations found that the cost of enabling decentralization over permissioned networks is almost negligible. Furthermore, delay towers offer an alternative to existing permissionless consensus mechanisms without requiring airdrops or pre-sale of tokens.