IBM TS4500, Введение и руководство по планированию

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streaming lossless data compression algorithm or enhanced streaming
lossless data compression algorithm depending on drive model.
Data buffer with read ahead feature
The TS1140, TS1150, and TS1155 tape drives include a data buffer of either
1 GiB or 2 GiB depending on model. Along with enabling performance
characteristics in buffered Write and Read commands, the data buffer also
supports a Read Ahead feature. When the drive processes a command to
locate or read a block, the drive automatically continues to stream down
the tape and read ahead until the data buffer is full. This feature allows
subsequent Locate or Read commands to be fulfilled from the data buffer
at faster speeds, rather than requiring access to the tape.
Offboard data string searching
The TS1140, TS1150, and TS1155 tape drives can search the data content of
host server records for string matches. The function is called offboard data
string searching because the data search workload can be done offboard
from the host. Each drive performs a search at its own respective
maximum data rate. This feature greatly reduces the amount of data
transfer and host search times.
Encryption
All TS1140, TS1150, and TS1155 tape drives are encryption capable, which
means they can convert data into a cipher that ensures data security. To
encrypt data, the drive must be encryption-enabled by your selection of
one of three methods of encryption management. A key is required to
encrypt and decrypt the data. How a key is generated, maintained,
controlled, and transmitted depends on the operating environment where
the tape drives are installed. Some data management applications can do
key management. For an alternative solution, IBM provides a key manager
that works with the keystore of your choice to do all necessary key
management tasks. There is no recovery for lost encryption keys.
For more information about encryption, see “Tape encryption overview” on
page 110. Also, refer to the IBM Encryption Key Manager and IBM Security
Key Lifecycle Manager (formerly Tivoli Key Lifecycle Manager )
publications that are listed in topic in “Related information” on page xv.
The 3592 tape drive supports five types of 3592 tape cartridges. For more
information about the supported cartridges, see “Supported tape cartridges” on
page 26.
Physical and logical addresses of drives
The TS4500 tape library assigns each tape drive a unique address to indicate its
physical location. The drive address consists of three values: a frame number, a
column number, and a row number.
Physical addresses
View drive location, and other information, on the Drives page of the TS4500
management GUI.
Frame number
Represented as
Fx
, where
F
equals the frame and
x
equals its number. The
leftmost frame in the library is always F1, regardless of whether it is a base
frame or not. The frame numbers increment by one for each frame to the
right of frame 1.
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IBM TS4500: Introduction and Planning Guide