MEV and Censorship
One of the main challenges in shared sequencing is the inability to prevent censorship and harmful MEV extraction. MEV (Maximal Extractable Value) refers to the value extracted by sequencers or validators who exploit the visibility of transactions and reorder them for profit. Harmful MEV includes the use of techniques like frontrunning or sandwiching, while censorship involves the exclusion of transactions within a block. These activities create a competitive and lucrative environment for sequencers and validators while leaving powerless users vulnerable to direct financial losses.
Rollups are particularly vulnerable to these risks since they often rely on a single centralized sequencer for scalability purposes. This sequencer has the monopoly power to reorder transactions, leaving users more vulnerable to harmful MEV and censorship attacks.
Radius employs a unique zero-knowledge cryptographic solution called PVDE (Practical Verifiable Delay Encryption) to prevent the centralized sequencer from exploiting its reordering power and building a profitable block. This encryption is rooted in the core design of Radius to protect users against harmful MEV and censorship. First, when users submit transactions, their transactions are automatically encrypted while the sequencer sequences them. The zk-proven encryption ensures that the sequencer cannot view the contents of the transactions before sequencing them, preventing them from manipulating the transaction order for their benefit.
To ensure liveness and prevent a single point of failure, Radius maintains a distributed set of sequencers while electing a single sequencer every epoch. This eliminates the need for consensus mechanisms that often come with performance tradeoffs over a single sequencer. With these measures in place, Radius creates a secure and reliable transacting environment for users.
Last modified 24d ago