Architecture Of Cognos :
Cognos has multi-layered architecture. It is basically separated in three layers of architecture. These tiers are based on business function and are typically separated by network firewalls. Cognos user interface sits above these layers. Below are the three tiers of Cognos architecture :
- Web Server
- Application Server
- Data Server
Tier 1 (Web Server) :
Web Communication in Cognos is typically through Gateways, which reside on one or more Web servers.Type of gateways supported are CGI, ISAPI, Apache_mod, servlet. When a Cognos 8 gateway receives a request, it encrypts password and extracts information needed to submit request to a Cognos 8 server. It then adds a default namespace to the request and passes the request to dispatcher for processing.
Tier 2 (Application Server) :
The Cognos applications tier contains one or more Cognos servers. A Cognos server runs requests, such as reports, analyses, and queries, that are forwarded by a gateway. A Cognos server also renders the Cognos Connection and Metric Studio interfaces.The main Application server component is Dispatcher, Content Manager and services like report service, log service, job service and presentation service, and so on, managed by Dispatcher.
- Dispatcher : Starts Cognos services configured and routes requests. It can route requests to a local service (report service, presentation service, job service and so on). It can also route requests to a specific dispatcher to run a given request.
- Content Manager : It is the Cognos service that manages the storage of application data, including security, configuration data, models, metrics, report specifications, and report output. Content Manager stores information in a content store database, which is typically located in Tier 3 of the architecture.
Tier 3 (Data Server) :
This Tier consists of Content Store database, Application database and Metrics store.
- Content Store : The content store is a relational database that contains data that Cognos needs to operate, such as report specifications, published models, and the packages that contain them; connection information for data sources; information about the external namespace, and the Cognos namespace itself; and information about scheduling and bursting reports.
- Application Database : This is the actual business data on which Cognos does the reporting.
- Metrics Store : A metric store is a relational database that contains content for metric packages. A metric store also contains Metric Studio settings, such as user preferences.
So this is the architecture of Cognos which makes it most powerful BI tool available in market.
Thanks for reading.