key per transaction using AES CCM, which is an authenticated encryption mode for AES that provides both
confidentiality and authentication.
The Reader only supports injection of keys during the manufacturing process; no remote key injection is
required as the Reader communicates directly with Square servers. During the manufacturing process, Square's
key provisioning equipment authenticates incoming Readers. Readers entering the key provisioning stage
authenticate the key-bundles received as having originated from Square's factory key provisioning module. The
Reader does not accept keys from any entity other than the factory provisioning module. Using the
Square-proprietary protocol, the cryptographic keys are injected into new devices in encrypted form. The
Square keys are injected and maintained under Square control and the details are transparent to the merchant.
The Reader does not provide or allow any user-configurable encryption key management functions.
Thank you for reading!
