Is the use of encryption mandatory in the Security Rule?From the HHS website - No. The final Security Rule made the use of encryption an addressable implementation specification. See 45 CFR § 164.312(a)(2)(iv) and (e)(2)(ii). The encryption implementation specification is addressable, and must therefore be implemented if, after a risk assessment, the entity has determined that the specification is a reasonable and appropriate safeguard in its risk management of the confidentiality, integrity and availability of e-PHI.