Industrial Communication Systems

18-1

18.1 Introduction

It is known that technologies to synchronize clocks are not an exclusive research topic of the computer

age.

As

a

matter

of

fact,

the

construction

of

highly

accurate

clocks

and

the

resulting

requirements

for

synchronization

date

back

to

the

seventeenth

century.

However,

the

actual

research

for

the

usage

in

distributed

systems

began

with

the

introduction

of

networked

computing.

e

issue

was

rst

discussed

in

depth

with

the

topic

of

event

ordering

by

Lamport

[Lamport1978].

A

good,

general

overview

on

available

algorithms

can

be

found

in

[Anceaume1997].

Later,

especially

with

the

upcoming

real-time

networks

[Kopetz1987,Pa ...