A printer generates a public key dependent on printer position information and transmits it to a print client. The print client encrypts a common key with this public key and transmits it to the printer, and encrypts print data with this common key and transmits it to the printer. The printer generates a private key dependent on printer position information to decrypt the encrypted common key, and decrypts the print data with the common key. Consequently, the printer capable of restricting the place where a print operation can be executed can be provided.