quick study

DHCP

Automatically assigns IP address settings

APIPA

169.254.x.x address when DHCP fails

DNS

Resolves domain names to IP addresses

Default Gateway

Router used to access external networks

NAT

Translates private IP to public IP

Bandwidth

Maximum data capacity

Throughput

Actual data transfer speed

Latency

Time delay in transmission

Jitter

Variation in packet delay

Packet Loss

Data lost during transmission

Router

Connects different networks

Switch

Connects devices within LAN using MAC addresses

Access Point

Provides wireless network access

Modem

Converts digital to analog for ISP connection

Firewall

Blocks unauthorized traffic

2.4 GHz WiFi

Longer range slower speed more interference

5 GHz WiFi

Faster speed shorter range less interference

SSID

Wireless network name

WPA2

Common secure wireless encryption

WPA3

Newest wireless encryption standard

FTP

21 file transfer

SSH

22 secure remote login

Telnet

23 insecure remote login

SMTP

25 email sending

DNS Port

53 name resolution

DHCP Ports

67/68 IP assignment

HTTP

80 web traffic

HTTPS

443 secure web traffic

POP3

110 email download

IMAP

143 email sync

SNMP

161 network monitoring

LDAP

389 directory services

RDP

3389 remote desktop

CPU

Executes instructions

RAM

Volatile temporary memory

SSD

Faster storage no moving parts

HDD

Slower mechanical storage

NVMe

Fastest storage using PCIe

POST

Checks hardware at startup

BIOS

Firmware for boot process

UEFI

Modern BIOS replacement

RAID 0

No redundancy fastest

RAID 1

Mirroring redundancy

RAID 5

Striping with parity fault tolerance

Power Supply

Converts AC to DC

Heat Sink

Dissipates heat

Thermal Paste

Improves heat transfer

Laser Printer

Uses toner and fuser

Inkjet Printer

Uses liquid ink

Thermal Printer

Uses heat paper

Fuser

Melts toner onto paper

Drum

Transfers toner to paper

Rollers

Move paper through printer

Ghosting

Repeating faded image issue

Paper Jam

Paper stuck in rollers

Streaks

Dirty drum or toner issue

Troubleshooting Steps

1 Identify the problem 2 Establish a theory 3 Test the theory 4 Establish a plan of action 5 Implement the solution 6 Verify full system functionality 7 Document findings

IaaS

Provides virtual hardware

PaaS

Provides platform for development

SaaS

Provides software over internet

Public Cloud

Shared environment

Private Cloud

Dedicated environment

Hybrid Cloud

Combination of both

Virtual Machine

Software-based computer

Hypervisor

Manages VMs

Hotspot

Shares mobile data connection

Bluetooth

Short-range wireless connection

NFC

Short-range payments communication

MDM

Manages mobile devices remotely

GPS

Location tracking system

Docking Station

Full laptop expansion

Port Replicator

Basic port expansion