Disk Subsystem system bus disk controller disks Multiple disks connected to a computer system through a controller Controllers functionality(checksum,bad sector remapping)often carried out by individual disks;reduces load on controller Disk interface standards families ATA(AT adaptor)range of standards SATA(Serial ATA) SCSI(Small Computer System Interconnect)range of standards SAS(Serial Attached SCSI) Several variants of each standard(different speeds and capabilities) Database System Concepts-6th Edition 10.14 ©Silberschat乜，Korth and SudarshanDatabase System Concepts - 6 10.14 ©Silberschatz, Korth and Sudarshan th Edition Disk Subsystem Multiple disks connected to a computer system through a controller Controllers functionality (checksum, bad sector remapping) often carried out by individual disks; reduces load on controller Disk interface standards families ATA (AT adaptor) range of standards SATA (Serial ATA) SCSI (Small Computer System Interconnect) range of standards SAS (Serial Attached SCSI) Several variants of each standard (different speeds and capabilities)