The WSIT Tutorial

Chapter 6 Using Reliable Messaging

This chapter explains how to configure reliable messaging in web service providers and clients.

This chapter covers the following topics:

Reliable Messaging Options

Table 6–1 describes the reliable messaging configuration options.

Table 6–1 Endpoint Reliable Messaging Configuration Options

Option 

Description 

Reliable Messaging

Specifies whether reliable messaging is enabled. 

Ordered Delivery

Specifies whether the Reliable Messaging protocol ensures that the application messages for a given message sequence are delivered to the endpoint application in the order indicated by the message numbers. 

This option increases the time to process application message sequences and may result in the degradation of web service performance. Therefore, you should not enable this option unless ordered delivery is required by the web service.

Flow Control

Specifies whether the Flow Control feature is enabled. When enabled, this option works in conjunction with the Max Buffer Size setting to determine the maximum number of messages for sequence that can be stored at the endpoint awaiting delivery to the application. Messages may have to be withheld from the application if ordered delivery is required and some of their predecessors have not arrived. If the number of stored messages reaches the threshold specified in the Max Buffer Size setting, incoming messages belonging to the sequence are ignored. 

Max Buffer Size

If Flow control is enabled, specifies the number of messages that will be buffered for a message sequence. The default setting is 32. For more information, see the description of the Flow Control option. 

Inactivity Timeout

Specifies the time interval beyond which either source or destination may terminate any message sequence due to inactivity. The default setting is 600,000 milliseconds (10 minutes). A web service endpoint will always terminate a sequence whose inactivity timeout has expired. To keep the sequence active, an inactive client will always send a stand- alone message with an AckRequested header to act as a heartbeat as the end of the Inactivity timeout interval approaches.

Creating Web Service Providers and Clients that use Reliable Messaging

Examples and detailed instructions on how to create web service providers and clients that use reliable messaging are provided in the following chapters:

Using Secure Conversation With Reliable Messaging

If Secure Conversation is enabled for the web service endpoint, the web service acquires a Security Context Token (SCT) for each application message sequence, that is, each message sequence is assigned a different SCT. The web service then uses that token to sign all messages exchanged for that message sequence between the source and destination for the life of the sequence. Hence, there are two benefits in using Secure Conversation with Reliable Messaging:

For more information on how to use Secure Conversation, see Chapter 7, Using WSIT Security.