hardware

Network cables

  • Copper wires in Ethernet cables have twists to reduce interference

  • Coaxial cables

  • Plenum-rated cable

  • Unshielded and shielded cables

    • (Overall cable) / (individual pairs)TP eg. S/FTP

Optical Fiber

  • Multimode fiber : up to 2km , LED (cheaper)

  • Singlemode fiber : up to 100km , lasers (expensive)

Cables

  • SATA data port (7 pin)

  • SATA power port (15 pin)

  • eSATA cable

Others

  • T568A and T568B are standards for wiring twisted pair network cables, including Ethernet cables

  • SCSI (communication standard like SATA)

  • SAS (Serial Attached SCSI)

  • daisy chain : wiring scheme , wire together in a ring

  • SATA (Serial-ATA (Advanced Technology Attachment) )

  • PATA (Parallel-ATA)

  • PCIe

  • BIOS (Basic Input/Output System)

  • UEFI BIOS replace legacy BIOS (a standardization for BIOS)

  • Reset BIOS : 1. CMOS Battery(remove and put back) 2.Clear CMOS Jumper(short 2 pins)

  • CPU: "32-bit" and "64-bit" refer to CPU architecture , CORES , MULTITHREADING , VIRTUALIZATION SUPPORT

  • DSL (Digital Subscriber Line) is a technology used to provide high-speed internet access over traditional telephone lines

  • ECC (Error Correcting Code) Memory

  • RAM parity (even parity check)

  • M.2 interface

  • AHCI vs NVMe

Printing

  • Laser printer (toner, a type of poweder)

  • Inkjet printer (ink)

  • Thermal pritner (uses thermal paper, eg. receipt paper (text will fade overtime))

  • Dot-martrix (impact) printer

  • 3D printer

Connectors

  • RJ11 (DSL)

  • RJ45 (ethernet)

  • F-connecter(for coaxial cable)

  • Molex connector (eg.computer PSU)

Power

PSU converts incoming electrical power (usually from an outlet) to the appropriate voltage required by the devices it powers

RAID

  • Stands for Redundant Array of Independant Disks

RAID 0 - Striping

  • Data is striped across 2 disks

  • Not fault tolerant

  • For speed

RAID 1 - Mirroring

  • Data is mirrored across 2 disks

RAID 5 - Striping with parity

  • Needs 3 or more disks

  • Data is rebuilt when a disk fails

RAID 10(1+0, or Mirroring + Striping)

  • Combines RAID 1 and RAID 0 by mirroring pairs of drives and then striping data across these mirrored pairs.

RAID Summary

RAID Level
Minimum Drives
Usable Space Formula
Fault Tolerance

RAID 0

2

Number of Drives x Size of Smallest Drive

No fault tolerance

RAID 1

2

Size of One Drive

1 drive

RAID 5

3

(Number of Drives - 1) x Size of Smallest Drive

1 drive

RAID 10

4

(Number of Drives / 2) x Size of Smallest Drive

1 drive per mirrored pair

Last updated