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About Siebel Enterprise Server and Siebel Server
The Siebel Enterprise Server is a logical grouping of Siebel Servers that connect to one Siebel Database. The Siebel Servers in a Siebel Enterprise Server are configured, managed, and monitored as a single logical group, allowing the Siebel administrator to start, stop, monitor, or set server parameters for all Siebel Servers within the Siebel Enterprise Server.
The Siebel Enterprise Server is composed of one or more Siebel Servers. Siebel Servers function as application servers and are composed of server components. Each server component performs a defined function.
Server components or groups of components determine what applications and services a Siebel Server supports. Components run in one of several modes:
- Interactive mode. Interactive components start tasks automatically in response to user requests. The tasks end when the user ends the session. Examples of interactive mode tasks are the Synchronization Manager and all Application Object Managers (AOMs).
- Background mode. Background components handle background processing tasks. Typically, background tasks are called by interactive mode tasks. Background tasks run until explicitly shut down. Examples of background tasks are Transaction Router and Workflow Monitor Agent.
- Batch mode. Batch mode components handle processing of asynchronous work requests. When the task is complete, the component exits. Examples of batch mode components are Database Extract and Enterprise Integration Manager (EIM).
Many of the Siebel Server components can operate on multiple Siebel Servers simultaneously. This allows Siebel applications to scale across many Siebel Servers to support large numbers of users.
Other Siebel Server components provide additional functionality besides application support. This includes the following:
- Siebel Mobile Web Client synchronization.
- Integration with legacy or third-party data.
- Automatic assignment of new accounts, opportunities, service requests, and other records.
- Workflow management.
- Document generation.
- Siebel Connection Broker (SCBroker). This server component provides load balancing for multiple Application Object Managers (AOMs) running on the same Siebel Server.
Implementation. The Siebel Server runs as a system service under Windows and a process under UNIX. This system service or process monitors and controls the state of all server components on that Siebel Server. Each Siebel Server is one instantiation of the Siebel Server system service or process within the current Siebel Enterprise Server.
Interactive mode and batch mode components can be configured to run as multiple processes or as multithreaded processes. Background mode components run as multiple processes only.
For information on administering the Siebel Server system service or process, see Siebel System Administration Guide.
Application Object Manager (AOM)
One of the most important types of server components is the Application Object Manager (AOM). These server components run in interactive mode. They process user requests and are application- or service-specific. For example, the Siebel Employee Relationship Management component group contains the Employee Relationship Object Manager. This Application Object Manager provides the session environment in which this application runs.
AOMs also contain a data manager, and the Siebel Web Engine. When an AOM receives a user request to start an application, it does the following:
- The business object layer starts an application user session, processes any required business logic, and sends a data request to the data manager.
- The data manager creates and SQL query and forwards it the database server.
- The data manager receives the data from the database and forwards it to the business object layer for additional processing.
- The business object layer forwards the result to the Siebel Web Engine, which helps create the UI for the data. The Siebel Web Engine then forwards the Web pages to the Siebel Web Server Extension on the Web server.
Implementation. An Application Object Manager (AOM) server component is implemented as a multithreaded process on the Siebel Server. At runtime, a parent process starts one or more AOMs as multithreaded processes, according to the AOM configuration. The terms multithreaded server or MT server are alternative terms for the multithreaded process.
Each thread in an AOM hosts tasks that are typically linked to one user session. These threads may be dedicated to particular user sessions, or they may serve as a pool that can be shared by user sessions. For each AOM, a few threads are dedicated to housekeeping functions.
Each AOM task uses the Siebel Server to communicate with the Siebel Database, the Web server (through the SWSE), and other Siebel Enterprise Server components:
- Communication with the Siebel Database uses ODBC database connections. Database connections can be managed and tuned for optimal performance. You can optionally configure connection sharing for database connections.
- Communication with the Siebel Web Server Extension uses SISNAPI (Siebel Internet Session API), a Siebel messaging format that runs on top of the TCP/IP protocol. SISNAPI connections can be configured to use encryption and authentication based on Secure Sockets Layer (SSL).
- Communication with other Siebel Enterprise Server components (including other Siebel Servers) also uses SISNAPI.
- The Siebel Connection Broker (SCBroker) on each Siebel Server listens on a static, configurable TCP port for requests coming from the Web server. SCBroker forwards these requests to AOMs.