The Problem

Table of Contents

PPT Slide

PPT Slide

The Problem

Clock Synchronization

Synchronizing Logical Clocks

Lamport Logical Clock

Lamport Clock (cont)

Physical Clocks

Atomic Clocks

Computer’s Clocks are not Accurate

Cristian’s Algorithm

Berkeley Unix Algorithm

Decentralized Averaging Algorithm

Clock Synchronization in DCE

Clock Synchronization in DCE (cont.)

The Network Time Protocol

Network Time Protocol (cont.)

Hierarchy in NTP

Synchronization in NTP

Synchronization in NTP (cont.)

Symmetric Mode

Calculating Offset and Accuracy

Adjusting the time

A Distributed Algorithm

Assumptions

Assumptions (cont.)

Algorithm’s Properties

Algorithm’s Properties (cont)

Operations

The Algorithm

The Algorithm (cont.)

Email: yairamir@cs.jhu.edu

Home Page: http://www.cs.jhu.edu/~yairamir/cs437/600-437.html

Other information:
Distributed Systems 600.437: Lecture 11. Clock Synchronization.