PPT-Paxos

A Consensus Algorithm for Fault Tolerant Replication CS 5204 Fall 2008 System Model Messages possible indefinite delay possible duplication or loss delivered messages not corrupted . lastclcamacuk ABSTRACT The Paxos algorithm is famously dif64257cult to reason about and even more so to implement despite having been synonymous with dis tributed consensus for over a decade The recently proposed Raft protocol lays claim to being a n Presenter-. Kurchi. . S. ubhra. . H. azra. Agenda. Basic Algorithms such as Leader Election. Consensus in Distributed Systems. Replication and Fault Tolerance in Distributed Systems. GFS as an example of a Distributed System. Advanced Topics in Computer Systems. Lecture 24. Paxos/Megastore. November . 26. th. , . 2012. John . Kubiatowicz. and Anthony D. Joseph. Electrical Engineering and Computer Sciences. University of California, Berkeley. Byzantine Fault Tolerance --- 1. Steve Ko. Computer Sciences and Engineering. University at Buffalo. Recap. Spanner. Geo-distributed database. Supports a relational data model with a SQL-like language. and Replicated State Machine (RSM). Outline. Basic Concepts of Replicated State Machine. Paxos. . Made Simple. Replicated State Machine. We can replicate data, how can we guarantee it is correctly replicated?. Cezara. . Drăgoi. , INRIA ENS CNRS. Thomas A. . Henzinger. , IST Austria. Damien Zufferey. , MIT CSAIL. SNAPL, 2015.05.04. Fault-tolerant distributed algorithms. How to get it right when things go wrong ?. Burcu Canakci & Matt Burke. . Outline. Consensus. The Part-Time Parliament. Single-Decree Paxos. Liveness. Multi-Decree Paxos. Paxos Variants. Conclusion. Outline. Consensus. The Part-Time Parliament. Fault Tolerant Replication. CS 5204 – Fall, 2008. System Model. Messages. possible indefinite delay. possible duplication or loss. delivered messages not corrupted. . . .. replicas. client. Replicas. . Distributed. . Systems. Crash. . Fault. . Tolerance. Sisi. . Duan. Assistant. . Professor. Information. . Systems. sduan@umbc.edu. Outline. A. . brief. . history. . of. . consensus. Paxos. Paxos Made Simple One-shot Paxos: solving consensus Multipaxos: Efficient state machine replication One-shot Paxos: solving consensus Multipaxos: Efficient state machine replication Consensus Get N nodes to agree on a value View Change Protocols and Consensus COS 418: Distributed Systems Lecture 11 Mike Freedman Today View changes in primary-backup replication Consensus 2 Review: Primary-Backup Replication Nominate one replica Consensus I FLP Impossibility, Paxos COS 418: Distributed Systems Lecture 7 Michael Freedman 2 Recall our 2PC commit problem C  TC: “go!” TC  A, B: “prepare!” A, B  P: “yes” Paxos and Replicated State Machine (RSM) Outline Basic Concepts of Replicated State Machine Paxos Made Simple Replicated State Machine We can replicate data, how can we guarantee it is correctly replicated? . Oct 22, 2018. What is consensus?. A group of people go to the same place for the same meal.. → A set of nodes have the same value for the same variable.. X=. 7. X=7. X=7. Why is it important?. In state machine replication (SMR):.