Copyright 2002 by
Prentice Hall, Inc.
Tier 3: the superserver/mainframe.
to include legacy applications, short-lived
and fast-changing data, and integrity rules.
Tier 2: specialized servers, dedicated to
housing databases or middleware-software
to ease connection between client and
Also, department-specific data that
does not change often.
Tier 1: clients, connected through network.
Types of Distributed Systems: