Pengantar Teknologi Informasi Fakultas Ekonomi UNPAR 4. Secondary Storage
Pengertian Storage : tempat penyimpanan Secondary Storage Storage Media Bus, controller : IDE, ATA, USB, … (dibahas di bab-5)
Tujuan Menyimpan data dan program : Permanen, tidak tergantung pada catu daya Backup, cadangan, keamanan Distribusi, memindahkan
Representasi Data Standard representasi: ASCII EBCDIC UNICODE
ASCII
Representasi biner Biner: data disimpan sebagai state ON = 1 OFF = 0
Standard Jumlah kode ASCII = American Standard Code for Information Interchange; ASCII-8 : 8 bit = 256 chars (0-255) EBCDIC = Extended Binary Coded Decimal Interchange Code; 256 chars UNICODE; Jika •1 huruf diwakili 1 char, dan •1 char ASCII-8 memerlukan tempat penyimpanan 8 bit (=1 byte), maka berapakah tempat untuk menyimpan “FE UNPAR” ? Berapa memory untuk menyimpan “FE UNPAR” dalam UNICODE?
Satuan 11 Byte = 8 bit 11 Kilobyte (KB) = 1024 Byte 11 Megabyte (MB)=1024 KB 11 Gigabyte (GB) = 1024 MB 11 Terabyte (TB) = 1024 GB bites? 1 MegaByte = 1,024 x 1,024 Bytes 1 MegaByte = 1,048,576 Bytes Kb = Kilobits KB = KiloBytes
Jenis Media penyimpanan: Magnetic Optical disk (Removable) Solid-state Storage Device
Magnetic MMagnetic Tape SSequential Access Storage Device (SASD) MMagnetic Disk DDirect Access Storage Device (DASD)
Magnetic Tape SSequential Access Storage Device (SASD) MMakin jarang digunakan, tapi masih ada dipakai untuk backup
Magnetic Disk Floppy disk (diskette) Hard disk
Magnetic Disk: diskette Bahan Bagian Track Sector
Floppy Disk (1) Ukuran
Floppy Disk (2) Formatting Soft-sector Hard-sector Kepadatan rekam Single Density Double Density Quad Density High Density Sisi rekam Single Side Double Side
Floppy Disk (3) Cluster : beberapa sector sebagai satu blok data Seandainya 1 cluster = 4 KB, maka File 3 KB memerlukan 1 cluster (4 KB) File 5 KB memerlukan 2 cluster (8 KB) Standard: FAT16 (DOS, Win31, Win95) = 32 KB FAT32 (Win98, XP) = 4 KB
Floppy Disk (3a) Diketahui disket, free space 100 KB Seandainya 1 cluster = 4 KB Disimpan file ukuran 5 KB Free space saat ini menjadi: 92 KB
Floppy Disk (4) High-capacity floppy disk Zipdisk (Iomega) Superdisk (Imation) HiFD disk (Sony)
Hard Disk (1)
Hard Disk (2) Seperti floppy
Hard Disk (3) Seperti floppy, bahan logam
Hard Disk (4) Seperti floppy, Beberapa piringan, cylinder
Hard disk (5) Speed: rotations per minute (rpm) Capacity: Giga Byte (GB) Transfer rate: Mega bit per second (Mbps) Controller: IDE, ATA, EIDE... Lihat bab-5, bus
Hard disk (6) : varian Removable hard disk RAID Redundant Array of Inexpensive Disks SCSI Small Computer System Interface
Hard disk, removable bracket •USB v1.1 data transfer 12Mbits/sec. •Compatible with almost every 2,5" hdd. •Hot swappable function. Included Win98/98se driver. Works without driver direct with Win ME/2000/XP, linux.
Hard Disk : RAID Redundant Array of Inexpensive Disks Beberapa disk murah Fitur tambahan High capacity Mirroring Fault tolerant Stripping
Optical Disk
ROM : Read Only Memory WORM : Write Once, Read Many CD-Recordable (CDR) Menulis CD dengan cara membakar (burn) permukaan piringan WMRM : Write Many Read Many ReWrite CD (CDRW)
Optical Disk CD (Compact Disk) : CD-ROM CD-R CD-RW mini-CD DVD (Digital Video Disk, Digital Versatile Disk) : DVD-ROM DVD-R DVD-RAM
CD Format: CD-Audio, CD-ROM (ISO), VCD, SVCD, CD-I,.. Kapasitas: Mini CD: 200 MB CD : 650 – 700 MB DVD : 4.7 GB – 17 GB Transfer rate: CD drive : 1x = 150 KBps DVD drive: 1x = 1.32 MBps
Fluorescent Multilayer Disk Capacity : 20 GB – 140 GB Transfer rate : 1 GBps
Solid State
Holographic