Reference
Network printer
A “network printer” is a printer with builtin print server functions. Laser printers
widely used in corporations are a type
of network printer. Clients can use a
network printer simply by connecting
the printer to a hub. However, a printer
driver must be installed for each client.
Reference
(2)Types of servers
In a client/server system, servers can be categorized according to their
role. The types of servers are summarized below.
Type of sever
Description
File server
A server that collectively manages files. Clients can share files on
the file server for effective use of information.
Print server
A server that manages and controls a printer. Clients temporarily
save print data to the hard disk of the printer server (spooling),
and after it is registered to a printing queue, the data is printed in
sequence.
Database server
A server with a DBMS (Database Management System). It can
produce an environment similar to one in which all clients are directly connected to the database. According to the requests of
the client, the database server performs processing such as
searching, tabulating, and sorting large amounts of data, and returns only the results to the client.
Database management
system
Refer to “Chapter 9-3-1 Database architecture.”
(3)Three-layer architecture
A “three-layer architecture” is a system that divides the applications of a
client/server system into three modules.
In a three-layer architecture, data is processed on the server side to limit
the amount of data transferred between the client and server.
Dividing the applications into three modules also makes it easier to change
the specifications.
A conventional and typical client/server system is called a “two-layer architecture.”
Hierarchy of three-layer architecture
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First layer
Presentation layer
Human interface level
Second layer
Application layer (Function layer)
Data processing level
Third layer
Data layer
Database access level