Yes. The ON CHANGE ONLY option on the Active Directory Receive Adapter provides this feature. A message is submitted to your BizTalk application only when the results of the query you have specified change. This feature provides a great way to trigger orchestrations and keep information in your Enterprise Applications synchronized.
There is also a REAL-TIME mode that gets events from Active Directory asynchronously and submits them to BizTalk as they happen.
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Both. The query is sent out by the send adapter. The actual querying is done by components of the receive adapter. Therefore, to be licensed to create Solicit-Response send ports, you need to be licensed for both the ActiveADAPTER send and receive adapters.
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