Field Level Encryption
Fields within a document can be securely encrypted by the SDK, to support FIPS-140-2 compliance.
Client-side implementation of Field Level Encryption was available in previous versions of the C, .NET, Go, Java, Node.js, PHP, and Python SDK.
It is being enabled in the 3.x SDKs, including PHP in near future. In the meantime, please check one of the currently enabled SDKs such as Python for a detailed overview of what to expect.