ICP DAS USA PDS-700 Series, Руководство пользователя

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PDS Series User Manual ( V1.4, Oct. 2009) ----- 180
16. Clients and Servers
The client-server paradigm uses the direction of initiation to categorize whether a
program is a client or server. In general, an application program that initiates peer to
peer communication is called a client. End users usually invoke client programs when
they use network services.
Most client programs consist of conventional application program develop tools. Each
time a client program is executed, it contacts a server, sends a request and waits for a
response. When the response arrives, the client program continues processing. Client
programs are often easier to develop than servers, and usually require no special
system privileges to operate.
By comparison, a server is any program that waits for incoming requests from a client
program. The server receives a request from a client, performs the necessary
computation and returns the result to the client.
17. Firmware
Firmware is an alterable program located or stored in the semi-permanent storage area,
e.g., ROM, EEPROM, or Flash memory.