This document outlines lecture 7 on consistency and replication in distributed systems. It discusses reasons for replication, issues that arise, different models of consistency including data-centric, client-centric and eventual consistency. It also covers topics like replica management, placement and protocols. The goal is to explain challenges in maintaining consistency across replicas and different approaches to addressing this.

1. Lecture 7- Consistency and Replication
Distributed Systems
Lecture 7: Consistency and Replication

2. Outline
• Introduction
• Reasons for Replication
• Issues in Replication
• Data-Centric Consistency
• Overview
• Continuous Consistency
• Ordering-Based Consistency
• Client-Centric Consistency
• Overview
• Eventual Consistency
• Client-Centric Consistency Models
• Replica Management
• Replica Server Placement
• Content Replication and Placement
• Content Distribution
• Consistency Protocols
• Primary-Based Protocols
• Replicated-Write Protocols
• Summary
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a proxy server is a server that acts as an intermediary for requests from clients and allows a
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38. Summary
• Introduction
• Reasons for Replication
• Issues in Replication
• Data-Centric Consistency
• Overview
• Continuous Consistency
• Ordering-Based Consistency
• Client-Centric Consistency
• Overview
• Eventual Consistency
• Client-Centric Consistency Models
• Replica Management
• Replica Server Placement
• Content Replication and Placement
• Content Distribution
• Consistency Protocols
• Primary-Based Protocols
• Replicated-Write Protocols
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