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9.1: Introduction to encryption > Asymmetric encryption - Pg. 102

9.1 Introduction to encryption Encryption is the process of transforming plain text into an unintelligible format, also known as cipher text , so that anyone who does not have the encryption key cannot access the data. Encryption is a critical technique for securing data, because even if an intruder gains physical access, they cannot interpret any of the information. If you do not know how the data was encrypted, it can range from hard to virtually impossible to decrypt the data. Encryption can be implemented in hardware or software: Hardware-based encryption Hardware-based encryption is performed by special processors in certain types of hardware (such as a tape drive, a network router, or a specialized appliance), which are very fast and can encrypt in real time. There is no impact to the data transfer rate and no CPU resources on the computer server are needed, because the encryption is off-loaded to other hardware. Software-based encryption Software-based encryption uses the server CPU to do the work. Because most computer CPUs are not specialized for encryption, this can take longer and consume CPU resources that otherwise are available for other operations. Tivoli Storage Manager can support both software encryption and hardware encryption. Software encryption is implemented within the Tivoli Storage Manager client. Hardware encryption is available with certain tape drives. While there are many methods of encryption, modern encryption methods can be classified as either symmetric or asymmetric encryption.