1. A data processing system, comprising: an application processor; a memory device; and a channel connecting the application processor and the memory device, wherein the application processor is configured to encrypt first data using a first encryption key and a first initialization vector in response to a write command, and transmit first encrypted data to the memory device through the channel, the memory device is configured to decrypt the first encrypted data using a second encryption key and a second initialization vector, and store first decrypted data in a memory core, and the second encryption key and the second initialization vector are stored in the memory device, the first encryption key is identical to the second encryption key, and the first initialization vector is identical to the second initialization vector.