ITteoric8.pdf

Week 8: Storage, Secondary (permanent) They are non-volatile storage mediums. Data remains on a given device unless rewritten or deleted. Types of Permanent Storage Devices Magnetic Flash Optical Online 1 Storage, Secondary, Magnetic An electromagnet cr...

Week 8: Storage, Secondary (permanent) They are non-volatile storage mediums. Data remains on a given device unless rewritten or deleted. Types of Permanent Storage Devices Magnetic Flash Optical Online 1 Storage, Secondary, Magnetic An electromagnet creates positive or negative charges on the disk surface. The charges create binary code read as the rotating disk and actuator arm work in conjunction. Magnetic Storage Types: 1. Hard Disk Drive (HDD) 2. Magnetic Tape Device 3. Floppy Disks 2 Storage, Secondary, Magnetic, HDD Data is read along concentric circles, known as tracks, and sectors, known as wedges. Benefits of high storage capacities and overall low cost, that’s why they are mostly used for backup and archiving purposes. Have a rotating head, that is why you will see specs like 7.5K RPM or 10K RPM (Revolutions Per Minute). 3 Storage, Secondary, Magnetic, Magnetic Tape Device Data is written onto magnetic tape along its length or width, though. At this point, magnetic tape is used in academic fields and countless other situations such as backup storage systems. Tape features higher storage capacities than hard drives, and they’re more reliable than HDDs. Researchers continue to develop magnetic tape for commercial use. 4 Storage, Secondary, Magnetic, Floppy Disks Relied on a magnetic disk that could be read and written via read/write heads. In the past, usually they were used to boot-up a computer (e.g older computers using MSDOS operating system could boot-up using a floppy disk). Most floppy disks held less than two megabytes of data, maxed out at 240 MB. 5 Storage, Secondary, Flash Rely upon flash memory to deliver blistering read/write speeds. Transistors are wired in series on a given circuit board. For that reason, data can be accessed immediately and without much noise or heat. Types: SSD (Solid State Drive) USB Flash Drive SD Card 6 Storage, Secondary, Flash, SSD SSDs cost more money than HDDs with similar storage capacities. Degrade in memory quality over millions of write operations, but they’re not susceptible to damage like hard drives.Plus, they’re quieter than hard drives and come in smaller form factors. Portable devices achieve better battery life due to the non-mechanical function. 7 Storage, Secondary, Flash, USB Flash Drive These devices are designed to be portable, pocketable storage solutions. They plug into a computer’s USB port and feature fast read/write speeds. They’re often used as backup devices for large amounts of data as well.Also, a variety of storage capacities are available on the market, although capacities over 256 GB are uncommon. 8 Storage, Secondary, Flash, SD Card Rely upon flash memory and are designed for portable devices such as cameras, smartphones etc. Most laptops and many smartphones feature SD Card readers. For sizing options, manufacturers offer full-size SD, miniSD, and microSD cards with various capacities. Categorized by their read/write speed, which can vary 12.5 megabytes per second to 3,938 MB/s. 9