Overview of WebSphere Application Server architecture

WebSphere Application Server is available in these editions:

• The base WebSphere Application Server product, which is fully J2EE-compliant and supports single machine environments.
• WebSphere Application Server Network Deployment, which expands on the functionality of the base product. WebSphere Application Server Network Deployment supports advanced Web services and clustering for workload management.

This page describes the architecture for both editions of the product.

• WebSphere Application Server
• WebSphere Application Server Network Deployment

WebSphere Application Server

This image represents the high-level architecture of WebSphere Application Server, Version 5.0 for iSeries:

The WebSphere Application Server architecture consists of these software components:

Software components that run on the iSeries server

• WebSphere Subsystem
  The WebSphere Application Server subsystem, QEJBAS5, contains the jobs that pertain to WebSphere Application Server. In addition to the jobs running in the QEJBAS5, your applications may also use jobs running in other subsystems. For more information on the jobs used in WebSphere Application Server, see WebSphere Application Server jobs.

• Application Server

  • Web Container
    The Web container runs within the application server and handles requests for servlets, JavaServer Pages^(TM) (JSP^(TM)) files, and the Web applications that contain them.

  • EJB Container
    The application server interacts with the EJB container to allow access to the enterprise beans contained within the EJB container. The EJB container provides an interface between the enterprise beans and the application server, providing many low-level services such as threading, support for transactions, and management of data storage and retrieval.

  • Java Message Service (JMS) Server
    WebSphere Application Server supports asynchronous messaging based on the Java Message Service (JMS) specification version 1.0.2 and supports the Application Server Facility (ASF) function defined within that specification. WebSphere Application Server provides an internal JMS provider and administration objects for MQSeries as the JMS provider. Use the internal JMS provider, install the MQSeries JMS on top of the WebSphere internal JMS, or install and configure another JMS provider.

    For an unfederated node, the internal JMS server runs within the application server. An unfederated node is an instance which is not part of a Network Deployment domain (cell). A federated node is an instance which has been added to a Network Deployment domain using the Network Deployment administrative console or the addNode script.

  • Name Server
    The Java Naming and Directory Interface, or JNDI, is used to provide access to Java components within a distributed computing environment. The WebSphere Application Server name server provides the implementation of this J2EE service, allowing you to bind WebSphere Application Server resources to JNDI names, and allowing client applications to access resources such as data sources, enterprise beans, message listeners, etc.

  • Security Server
    The WebSphere Application Server security server provides security infrastructure and mechanisms to protect sensitive J2EE resources and administrative resources and to address enterprise end-to-end security requirements on authentication, on resource access control, on data integrity, confidentiality, and privacy, and on secure interoperability.

• MQ Series subsystem
  If you are using the embedded JMS server which comes with the WebSphere Application Server product, the MQ Series subsystem, QMQM, contains jobs that pertain to WebSphere Application Server. These jobs represent the embedded JMS server and are used to process JMS messages. For more information on the jobs running in the QMQM subsystem to support the embedded JMS server, see Other jobs used by WebSphere Application Server.

Software components that run on a client workstation

• Browser
  A Web browser that supports HTML 4.0 and CSS Cascading Style Sheets (CSS) and has cookies enabled.

• Administrative Console
  The Administrative Console is a browser-based graphical interface that allows you to configure and manage WebSphere Application Server resources. For more information about the Administrative Console, see The administrative console.

WebSphere Application Server Network Deployment

This image represents the high-level architecture of WebSphere Application Server Network Deployment, Version 5.0 for iSeries:

In addition to the components that make up the WebSphere Application Server architecture, the WebSphere Application Server Network Deployment architecture includes these software components:

Software components that run on the iSeries server

• Network Deployment Subsystem
  The WebSphere Application Server Network Deployment subsystem, QEJBASND5, contains the jobs that pertain to Network Deployment. The QEJBASND5 subsystem contains the application server job for each Deployment Manager running on your iSeries.

• Deployment Manager
  The Deployment Manager is an administrative application which runs in a specialized application server. The application server and the administrative application are installed when you install the WebSphere Application Server Network Deployment product. The Deployment Manager allows you to manage multiple WebSphere Application Server instances, or nodes, as a group. This logical grouping of nodes, managed by a single Deployment Manager instance, form a Network Deployment cell.

  Deployment managers also host logic for creating and controlling clusters, and for balancing the work load of application servers across several nodes.

  Administrative tools that need to access any managed resource in a domain usually connect to the deployment manager for the domain as a central point of control. The deployment manager provides a single, central point of administrative control for all elements of the entire WebSphere distributed cell.

• Node Agent
  Node agents are servers that monitor application servers running in a WebSphere Application Server instance and route administrative requests to the application servers. If your WebSphere Application Server instance is not part of a Network Deloyment cell, there is no node agent server for the instance.

  There is one node agent for each WebSphere Application Server instance which has been added to a Network Deployment cell.

  The node agent is used purely for administrative funtions and is not involved in application serving functions. A node agent also hosts other important administrative functions such as file transfer services, configuration synchronization, and performance monitoring.

• JMS Server
  WebSphere Application Server supports asynchronous messaging based on the Java Message Service (JMS) of a JMS provider that conforms to the JMS specification version 1.0.2 and supports the Application Server Facility (ASF) function defined within that specification. WebSphere Application Server provides an internal JMS provider and administration objects for MQSeries as the JMS provider. Use the internal JMS provider, install the MQSeries JMS on top of the WebSphere internal JMS, or install and configure another JMS provider.

  For a federated node, the internal JMS server runs in its own job separate from application server process. A federated node is an instance which is part of a Network Deployment cell.