HP StorageWorks 1/8, User'S And Service Manual, Page: 20 / 204

CAUTION:
High quality SAS cables rated at the transfer rate of the SAS components are required. Always verify
that the SAS cable you are using is rated for the data transfer speed of the interface of your
components. SAS cables described as "equalized" may not support 6 Gb/s data rates and should
not be used with LTO-5 tape drives unless these cables are verified for 6 Gb/s data rates. For optimum
performance, only use HP cables of the length specified as qualified for your products.
See “ About SAS ” on page 29 for more information about SAS.
LTO-4 and later generation tape drives and encryption
The LTO-4 and later generation tape drives include hardware capable of encrypting data while writing
data, and decrypting data when reading. Hardware encryption can be used with or without
compression while maintaining the full speed and capacity of the tape drive and media.
Encryption is the process of changing data into a form that cannot be read until it is deciphered with
the key used to encrypt the data, protecting the data from unauthorized access and use. LTO tape
drives use the 256-bit version of the industry-standard AES encrypting algorithm to protect your data.
To make use of this feature you need:
• The HP StorageWorks 1/8 G2 & MSL Encryption Kit or a backup application that supports
hardware encryption.
• LTO-4 or LTO-5 media; no encryption will be performed when writing LTO-3 and earlier generations
of tape.
Table 9 Backward read compatibility
LTO-5 drive LTO-4 drive
Incompatible Incompatible LTO-1 media
Incompatible Read only LTO-2 media
Read only Read/Write (no encryption) LTO-3 media
Read/Write Read/Write LTO-4 media — unencrypted
Read/Write with encryption key Read/Write with encryption key LTO-4 media — encrypted
Read/Write Incompatible LTO-5 media — unencrypted
Read/Write with encryption key Incompatible LTO-5 media — encrypted
Your company policy will determine when you need to use encryption. For example, it may be
mandatory for company confidential and financial data, but not for personal data. Company policy
will also define how encryption keys should be generated and managed. Backup applications that
support encryption will generate a key for you or allow you to enter a key manually.
Features and overview 20