Abstract: Examples and techniques pertaining to a security mechanism for multi-client access to a single storage device through a single controller are described. A controller receives a request from a first client of a plurality of clients to access a storage device which stores data associated with the plurality of clients. The controller determines one or more aspects with respect to the first client. The controller then performs one of a plurality of operations including: (a) granting the first client access the storage device responsive to a positive result of the determining, and (b) rejecting the request responsive to a negative result of the determining. The storage device is divided into a plurality of partitions to store respective data associated with each of the plurality of clients in one or more respective partitions of the plurality of partitions.