Guaranteed delivery. This feature ensures that a service executes once and only once. It is particularly useful when used with clustering to prevent a restarted service from running on more than one server. This feature is only for use with server-to-server communications.

Checkpoint restart services. The pub.storage services allow you to code your flow service to store state information and other pertinent information in the short-term data store. If the flow service fails because a server becomes unavailable, the flow service can be restarted from the last checkpoint rather than at the beginning. For more information about pub.storage services, see the webMethods Integration Server Built-In Services Reference.