Unit 3.2 Cybersecurity Terms

Solid State Drive

Uses flash memory technology for persistent mass storage, better performance than HDD’s.

Flash Memory

Data storage that retains memory when the device is powered off and uses electricity to erase and reprogram itself.

Wear Leveling

evenly distribute writing across all blocks, optimizing the device's lifespan.

NAND Flash Memory

comes in different types. Single-level-cell (SLC) is more reliable and expensive than multi-level cell types.

SATA SSD

SSDs may be packaged in a 2.5-inch caddy and connected using standard SATA data and power connectors.

PCIe SSD

Modern SSDs often use the PCIe bus directly, utilizing the Non-Volatile Memory Host Controller Interface Specification (NVMHCI) or NVMe interface for better performance. NVMe SSDs can be installed in a PCIe slot as an expansion card or in an M.2 slot.

NVMe

Non-Volatile Memory Express. Internal interface for connecting flash memory devices, such as SSDs, directly to a PCI Express bus. NVMe allows much higher transfer rates than SATA/AHCI.

SAS

interface used for high-performance storage devices, often in enterprise environments. Faster transfer rates, better reliability than SATA. Point-to-point connections, used in workplaces.

Hard Disk Drive

stores data on metal or glass platters coated with a magnetic substance. Each platter has a read/write head on both sides, moved by an actuator mechanism.

Platter

Metal disk that stores data in a Hard Disk Drive.

Spindle

Spins platters at high speeds.

Read/Write Head

On both sides in a hard disk drive, moved by an actuator mechanism.

Actuator

Moves read/write head.

Drive Geometry

Each side of a platter is divided into circular tracks, which are further divided into sectors, each holding 512 bytes.

Spindle Speed

measured in revolutions per minute (RPM). High-performance drives spin at 15,000 or 10,000 RPM, while average drives spin at 7,200 or 5,400 RPM.

Seek Time

the time it takes to move to the data's position.

Access/Read Time

the delay as the read/write head locates a track

Transfer Rate

measures how fast read/write operations are performed on the platters. A 15,000 RPM drive supports up to 180 MBps, while a 7,200 RPM drive supports around 110 MBps.

RAID

Redundant Array of Independent Disks. RAID works by distributing data across multiple disks to provide fault tolerance and improve performance.

Fault Tolerance

Protection against system failure by providing extra (redundant) capacity. Generally, fault tolerant systems identify and eliminate single points of failure. Fault tolerance is also known as "redundancy."

RAID 0

Striping drive configuration. Provides no redundancy against device failure.

RAID 1

Mirrored two-disk redundant drive configuration with 50% capacity utilization.

RAID 5

Striping with parity-redundant drive configuration supporting a flexible number of devices and better than 50% capacity utilization.

RAID 10

Stripe of mirrored four-disk redundant drive configuration with 50% capacity utilization. A RAID 10 volume can support the loss of one device in each mirror.

Parity

error correction information is spread across all the disks in the array.

Hot-Swapping

faulty units can be replaced without opening the case or interrupting power to the system.

RAID Controller

Adapter card to control RAID drives. Entry-level controllers might support only RAID 0 or RAID 1, while mid-level controllers might add RAID 5 and RAID 10.

Drive Enclosure

provides a data interface (such as USB, Thunderbolt, or eSATA), a power connector (if needed), and physical protection for the disk.

NAS

Network Attached Storage

Flash Drive

Consists of a flash memory board with a USB connector and a protective cover. You can plug it into any available USB port on your computer.

Memory Card

Solid state flash memory provisioned as a peripheral device in proprietary adapter card form factors, such as Secure Digital and microSD.

Multi-Card Reader

Can read multiple types of cards. There are several proprietary types of memory cards, each with different sizes and performance levels.

CD and Types

Optical storage technology supporting up to 700 MB per disc with recordable and re-writable media also available.

DVD and Types

Capacity: 4.7 GB (single-layer, single-sided) to about 17 GB (dual-layer, double-sided). Formats: DVD+R/RW and DVD-R/RW (most drives support both, indicated by the ± symbol). Bast Transfer Rate: 1.32 MBps (equivalent to 9x CD speed)

BD and Types

Capacity: 25 GB per layer. Formats: Read-only(BD-ROM) and Rewritable(BD-RE). Base Transfer Rate: 4.5 MBps, with a maximum theoretical rate of 16x(72MBps).

Laser

reads data encoded on the disc surface.

Region Coding

restricts disc usage to players from the same region. On PCs, the region can be set via device properties but is usually limited to a few changes by the firmware.

DRM

Digital Rights Management.