Network Deployment (Distributed operating systems), v8.0 > Applications > Web services > WS-Notification
WS-Notification: Benefits
WS-Notification enables web services to use the publish and subscribe messaging pattern. This approach offers many business benefits.
WS-Notification provides a standardized approach for web service applications to participate in the publish and subscribe messaging pattern, whether this be listening for notification of a particular event occurrence, or inserting event notifications into the system for consumption by other applications or system management tooling. The open-standards nature of this web services specification mean that applications can communicate with each other irrespective of the underlying hardware platforms, software languages or vendor environments. The WS-Notification implementation in WAS supports the WS-Notification standards, complies with the WS-I Basic Profile 1.0 requirements, and composes with other related standards such as WS-Addressing for High Availability and Workload Management, and WS-ReliableMessaging for reliable communication between components.
Within WAS, the NotificationBroker is implemented to provide flexible support for enterprise topologies including high availability and work load management patterns. This support for WS-Notification also allows interchange of event notification between WS-Notification applications and other clients of the service integration bus. By exploiting other service integration bus functions you can also use this function to interchange messages with other IBM publish and subscribe brokers such as WBI Event Broker or Message Broker.
Rather than receiving all messages on a topic to which we have subscribed, your consuming application can use XML Path (XPath) selectors to filter the messages based upon the contents of each message. This content-based subscription gives greater flexibility in defining the type of information to receive, the applications can use it to avoid responsibility for their own filtering, and it improves performance by not flowing messages unnecessarily from the server to the application.
WAS offers two WS-Notification service and service point options:
- Version 7.0 : Use this type of service to compose a JAX-WS WS-Notification service with web service qualities of service (QoS) via policy sets, or to apply JAX-WS handlers to your WS-Notification service. This is the recommended type of service for new deployments. This WS-Notification option has been available in WAS from v7.0.
- Version 6.1 : Use this type of service to expose a JAX-RPC WS-Notification service that uses the same technology provided in WAS v6.1, including the ability to apply JAX-RPC handlers to the service. This WS-Notification option has been available in WAS from v6.1.
The v7.0 WS-Notification option allows you to use web services-based publish/subscribe messaging in a reliable way, through a standards-based connection mechanism, in an environment where network connectivity is not always available. For example, to use the Internet to send warehouse or stock level notifications to remote customers, ensure that messages reach customers reliably so that they have accurate stock levels for sales and production planning. We can achieve this by composing JAX-WS based v7.0 WS-Notification services (for stock level notification) with WS-ReliableMessaging (to ensure reliable delivery of notifications).
The main benefits of a v7.0 WS-Notification service over a v6.1 WS-Notification service are as follows:
- It is easier to configure using policy sets.
- It supports JAX-WS handlers.
- It avoids the need to install an SDO repository.
WS-Notification
Use WS-Notification for publish and subscribe messaging for web services
Secure WS-Notification
Related
http://www.research.ibm.com/journal/sj/444/niblett.html
http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=wsn
WS-Notification troubleshooting tips
Concept topic