Oracle7 Server Distributed Systems Volume I: Distributed Data
The Components of the Client-Server Model
The client-server model consists of three parts:
The Client
The client is the machine (workstation or PC) running the front-end applications. It interacts with a user through the keyboard, display, and pointing device such as a mouse. The client also refers to the client process that runs on the client machine.
The client has no direct data access responsibilities. It simply requests processes from the server and displays data managed by the server. Therefore, the client workstation can be optimized for its job. For example, it might not need large disk capacity, or it might benefit from
graphic capabilities.
This simple client view is necessary to allow many different client-server implementations, ranging from PCs to mainframes and different client interfaces to store and retrieve data. To support this client environment, Oracle7 fully implements the ANSI/ISO SQL standard and interfaces.
The Server
The server is the machine that runs Oracle7 software and handles the functions required for concurrent, shared data access. It is often referred to as the back-end. Server also refers to the server process that runs on the server machine.
The server receives and processes SQL and PL/SQL statements originating from client applications. The server can also be optimized for its duties. For example, it can have large disk capacity and fast processors. It can also take the load of disk I/O, printing, file transfer, and so on.
The Network
The network enables remote data access through client-server and server-to-server communication. Oracle's Network Products allow databases and applications to reside on different machines with different operating systems while still communicating as peer applications.