Executing and Proving over Dirty Ledger

Στέφο, Χρήστος; Stefo, Christos

dc.contributor.author	Στέφο, Χρήστος	el
dc.contributor.author	Stefo, Christos	en
dc.date.accessioned	2023-01-26T10:25:46Z
dc.date.available	2023-01-26T10:25:46Z
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/56939
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.24637
dc.rights	Default License
dc.subject	Κρυπτογραφία	el
dc.subject	Κατανεμημένοι Αλγόριθμοι	el
dc.subject	Μηχανή Καταστάσεων	el
dc.subject	Επίπεδο Διάταξης	el
dc.subject	Επίπεδο Εκτέλεσης	el
dc.subject	State Machine Replication	en
dc.subject	Blockchains	en
dc.subject	Ordering Layer	en
dc.subject	Execution Layer	en
dc.subject	Light Clients	en
dc.title	Executing and Proving over Dirty Ledger	en
heal.type	bachelorThesis
heal.classification	Distributed Algorithms	en
heal.classification	Cryptography	en
heal.classification	Distributed Consensus	en
heal.language	el
heal.language	en
heal.access	free
heal.recordProvider	ntua	el
heal.publicationDate	2022-11-01
heal.abstract	Scaling blockchain protocols to perform on par with the expected needs of Web3.0 has been proven to be a challenging task with almost a decade of research. In the forefront of the current solution is the idea of separating the execution of the updates encoded in a block from the ordering of blocks. In order to achieve this, a new class of protocols called Rollups has emerged. Rollups have as input a total ordering of valid and invalid transactions and as output a new valid state-transition. If we study rollups from a distributed computing perspective, we uncover that rollups take as input the output of a Byzantine Atomic Broadcast (BAB) protocol and convert it to a State Machine Replication (SMR) protocol. BAB and SMR, however, are considered equivalent as far as distributed computing is concerned and a solution to one can easily be retrofitted to solve the other simply by adding/removing an execution step before the validation of the input. This "easy'' step of retrofitting an atomic broadcast solution to implement an SMR has, however, been overlooked in practice. In this paper, we formalize the problem and show that after BAB is solved, traditional impossibility results for consensus no longer apply towards an SMR. We propose multiple distributed execution protocols that allow for n<3f+1 without relaxing the network assumptions of the underlying BAB protocol. Finally, we propose efficient non-interactive light client constructions that leverage our efficient execution protocols and do not require any synchrony assumptions or expensive ZK-proofs.	en
heal.advisorName	Παγουρτζής, Αριστείδης	el
heal.committeeMemberName	Παγουρτζής, Αριστείδης	el
heal.committeeMemberName	Φωτάκης, Δημήτριος	el
heal.committeeMemberName	Ελευθέριος, Κόκορης-Κόγιας	el
heal.academicPublisher	Εθνικό Μετσόβιο Πολυτεχνείο. Σχολή Ηλεκτρολόγων Μηχανικών και Μηχανικών Υπολογιστών	el
heal.academicPublisherID	ntua
heal.fullTextAvailability	false