Enterprise security requires a comprehensive approach for defense in depth. Effective immediately, Azure Search now supports encryption at rest for all incoming data indexed on or after January 24, 2018, in all regions and SKUs including shared (free) services. With this announcement, encryption now extends throughout the entire indexing pipeline – from connection, through transmission, and down to indexed data stored in Azure Search.
At query time, you can implement user-identity access controls that trim search results of documents that the requestor is not authorized to see. Enhancements to filters enable integration with third-party authentication providers, as well as integration with Azure Active Directory.
Read about it in the Azure blog.