. "Technological protection measures (TPM) encompass software, devices or other technologies used to block or limit access to a work, or certain actions with respect to the work (e.g., copying). TPMs include such things as encryption, passwords, and access controls."@en . . . "Technological protection measures"@en . . "Technological protection measures (TPM) encompass software, devices or other technologies used to block or limit access to a work, or certain actions with respect to the work (e.g., copying). TPMs include such things as encryption, passwords, and access controls."@en . .