Professor Messer CompTIA A+ 1101

TN acronym

Twisted Nematic

LCD acronym

Liquid Crystal Display

How does LCD display work?

Light shines through liquid crystals

Advantages of LCD display

Lightweight, low power, relatively inexpensive

Disadvantages of LCD display

Black levels are a challenge, require separate backlight, and lights are hard to replace

Twisted Nematic (TN) LCD

The original LCD tech with fast response time but with poor viewing angles (color shifts)

In Plane Switching (IPS) LCD

Excellent color representation but expensive

Vertical Alignment (VA) LCD

Good compromise between TN and IPS LCD, has good color representation but has slower response times

OLED acronym

Organic Light Emitting Diode

IPS acronym (display)

In Plane Switching

TN acronym (display)

Twisted Nematic

VA acronym (display)

Vertical Alignment

OLED (Organic Light Emitting Diode)

Organic compound emits light when receiving electric current, very thin and light, no backlight.

Where is a Wi-Fi antenna commonly located on a laptop?

Inside at the top of the monitor, the wires wrap all the way around the monitor and attach to the system board.

What is 802.11

international standard for wireless networking

CCFL acronym (display)

Cold Cathode Fluorescent Lamp

What is CCFL backlighting?

Cold Cathode Fluorescent Lamp

No longer common

Higher voltage and power needed

Used a power inverter for DC to AC power

Added thickness to display

LED acronym

Light Emitting Diode

What is LED backlighting?

Backlight is LEDs instead of fluorescent

Can have LEDs around the edge (diffused to light evenly) on smaller screens, or array of LEDs behind the screen on larger displays/TVs

LED arrays can be dimmed individually

What do LCD displays require?

Backlight

Some laptops have ______ that turn DC into AC for backlighting

inverters

Sometimes you may need to replace the LCD ______ or ________

inverter, display

What is a digitizer?

a device for converting analogue signals into digital signals.

What are digitizers for laptops, tablets, or hybrid devices typically used for?

stylus input or finger input

USB acronym

Universal Serial Bus

What is USB?

high-speed wired communication

used for charging and data transfer

What is Micro-USB?

smaller USB connection

common now worldwide

What kind of devices may use Mini-USB (Mini B)?

Older devices

How can you tell the difference between micro usb and mini usb?

Mini USB is slightly larger

USB-C

24-pin double-sided USB connector

What kind of connections can USB-C act as?

USB 2.0/3.0/3.1/4

What are some of the signals that USB-C can transmit?

DisplayPort

HDMI

Thunderbolt

Lighting Cable

Apple Propietary cable/port

8 pin digital signals

What cable does lightning have advantages over?

Micro-USB

What advantages does Lightning have over Micro-USB?

higher power output for phones and tablets

can be inserted on either side

simple design

Different name for DB-9 cables

DE-9

What is a DB-9 connector?

commonly used for RS-232 signals

transported RS-232 signals

traditionally used for modem connections

uncommon nowadays

NFC (acronym)

Near Field Communication

What is NFC used for?

sends small amounts of data wirelessly over a limited area

What is bluetooth?

a wireless PAN technology that transmits signals over short distances among cell phones, computers, and other devices

PAN (acronym)

Personal Area Network

What is a hotspot?

a wireless network that provides Internet connections to mobile computers and devices

What are touch pens?

stylus that interacts with device touchscreens without physically touching the screen with your hand

Functions of an Active Stylus / Digital Stylus

more advanced writing tool that has pressure sensitivity, programmable buttons, active stylus are typically specific to certain devices

Functions of a drawing pad

uses an active stylus and an external digitizer for very precise input, third-party device that is supported by many devices

Some laptops you are able to _______ trackpads.

disable

Headsets

earphones and microphone combination

USB connections are common on laptops

connects to 3.5 mm TRRS (tip-ring-ring-sleeve) connector

analog audio jack

iPhone can use lightning port

can be used for bluetooth

TRRS acronym

Tip Ring Ring Sleeve

What is a TRRS connector?

Tip Ring Ring Sleeve connection that enables microphone and audio functionality

What is a Docking Station

A device designed to more easily connect a portable computer to peripheral devices, such as a keyboard, mouse, monitor, and printer

What is a port replicator?

A port replicator plugs into a single port (often USB) and offers additional ports

What is a cellular network?

a mobile network that provides services by using a large number of base stations with limited power, each covering only a limited area

What are cells in cellular networking?

antenna coverage in a certain area

What are 2G networks?

Some of the earliest cellular networks were based on:

GSM- Global System for Mobile Communications

CDMA- Code Division Multiple Access

What was the problem with 2g cellular networks?

poor data support

originally used circuit-switching

GSM acronym

Global System for Mobile Communications

What is GSM? (Global System for Mobile Communications)

mobile networking standard

was originally an EU standard

was 90% of the market

used by AT&T and T-Mobile in the US

original GSM standard used multiplexing

CDMA acronym

Code Division Multiple Access

What is CDMA? (Code Division Multiple Access)

everyone communicates at the same time

each call uses a different code

the codes are used to filter each call on the receiving side

was used by Verizon and Sprint

handsets are controlled by the network provider

not much adoption around the world

What is 3G technology?

introduced in 1998

3G received incremental updates that added several megabits per second

The bandwidth upgrades that was included in 3G cellular technology was what?

GPS

mobile TV

video on demand

What kind of technology is LTE?

a 4G technology

LTE acronym

Long Term Evolution

What did LTE (long term evolution) cellular technology accomplish?

converged GSM and CDMA providers onto one standard

What was LTE based on?

LTE was based on EDGE (Enhanced Data Rates for GSM Evolution)

How fast was the LTE standard?

150 Mbps

What is LTE-A (LTE Advanced)?

upgraded LTE standard that doubled throughput to 300 Mbps

What is 5G?

fifth generation cellular networking introduced in 2020

What will 5G cellular technology accomplish?

Larger bandwidth up to 10 Gbps

IoT acronym

Internet of Things

What is internet of things?

the idea that everything / every device could be given an ip address and put on the internet. Ex. using your phone to turn on your microwave

How does 5G impact IoT (internet of things)?

bandwidth becomes less of a constraint and allows more devices on a network

What is PRL (Preferred Roaming List) updates?

allows your phone to understand where all the appropriate towers for the network it happens to be using

PRL acronym (mobile devices)

Preferred Roaming List

OTA acronym (mobile devices)

Over the Air

Function of a hotspot on a smartphone

turns your phone into a wireless router

extends the cellular data network to any device that connects to it

What is Microsoft 365?

productivity cloud designed to help you run your business

What is iCloud?

cloud storage for apple products like iOS and iPadOS

What is network topology?

ethernet, DSL, switches, routers

What is IP?

Internet Protocol: An addressing system that finds paths to distant computers

TCP acronym (networking)

Transmission Control Protocol

What is TCP?

transmission system that sends and tracks binary sequences of data that are split into small packets sent separately

What is UDP?

sends packets without verifying or checking for errors

UDP acronym (networking)

User Datagram Protocol

TCP and UDP are _______ inside of IP

transported

What are the two protocols for moving data in networking?

TCP and UDP

What layer is TCP and UDP?

transport layer or layer 4

What is multiplexing?

allows the use of many different applications at the same time

TCP and UDP provide _______ that IP can't provide alone

multiplexing

TCP often refer to as a _______

connection-oriented protocol

tcp/389

LDAP (Lightweight Directory Access Protocol)

tcp/80

HTTP (Hypertext Transfer Protocol)

tcp/110

POP3 (Post Office Protocol version 3)

tcp/3389

RDP (Remote Desktop Protocol)

tcp/25

SMTP (Simple Mail Transfer Protocol)

tcp/445

SMB (Server Message Block)

udp/161

SNMP (Simple Network Management Protocol)

tcp/143

IMAP (Internet Message Access Protocol)

tcp/22

SSH (Secure Shell)

tcp/23

Telnet Port