12-04-2011, 11:30 AM
PRESENTED BY
ANIL.L
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CLIENT/SERVER ARCHITECTURE
Architectural Design for Client/Server Systems
• The architectural design of a client/server system is often characterized as a communicating processes style.
• The goal is to achieve the quality of scalability.
TRANSACTION BETWEEN CLIENT/SERVER
• A server exists to serve data to one or more clients, which are typically located across a network.
• The client originates a call to the server, which works, synchronously or asynchronously, to serve the client’s request.
• If the server works synchronously, it returns control to the client at the same time it returns data.
• If the server works asynchronously, it returns only data to the client
BASIC CLIENT/SERVER ARCHITECTURE
• Modern c/s systems are component based, an OBJECT REQUEST BROKER(ORB) architecture is used to implement this synchronous or asynchronous communication.
• At the architectural level, the INTERFACE DESCRIPTION LANGUAGE(IDL) is used to specify interface details.
• The use of IDL allows application software components to access ORB services (components) without knowledge of their internal workings.
• The ORB also has the responsibility for coordinating communication among components for both the client and server.
• To accomplish this, the designer specifies an object adapter (also called a wrapper) that provides the following services
• Component (object) implementations are registered.
• All component (object) references are interpreted and reconciled.
• Component (object) references are mapped to the corresponding component implementation.
• Objects are activated and deactivated.
• Methods (operations) are invoked when messages are transmitted.
• Security features are implemented