CompTIA A+ Core 1

What is Random Access Memory (RAM)?

RAM is the memory bank currently in use by a computer or device; it is temporary storage.

What is Virtual RAM?

Virtual RAM is space on a hard drive allocated for additional memory when requested by an application, also known as a swap file or paging file.

What is a Small Outline Dual Inline Memory Module (SODIMM)?

SODIMM is a type of RAM commonly found in laptops, characterized by its compact size and various pin configurations.

What are the benefits of Double Data Rate 3 (DDR3) RAM?

DDR3 is faster than DDR2 and has 30% less power consumption, available in different DIMM and SODIMM pin configurations.

What does Double Data Rate 4 (DDR4) offer over DDR3?

DDR4 is faster than DDR3 with improved power consumption, coming in 288-pin DIMM and 260-pin SODIMM.

How does Double Data Rate 5 (DDR5) improve memory performance?

DDR5 doubles the speed of DDR4 to 6.4 Gbps with better power efficiency at 1.1 volts and up to 128 GB modules.

What is Error-Correcting Code (ECC) RAM?

ECC RAM has logic built to detect and correct single-bit memory errors, improving data integrity.

What is the difference between Single Channel and Dual Channel memory?

Single channel transfers data in chunks the size of the system bus' bandwidth, while dual channel coordinates two memory banks to double data transfer size.

What are the characteristics of SSDs?

SSDs use flash memory technology with no moving parts, providing high speed and smaller form factors than HDDs.

What are the main types of communications interfaces for SSDs?

The main types are NVMe (fastest), PCIe (faster than SATA), and SATA (slowest).

What is the M.2 form factor?

M.2 is a compact SSD form factor measuring 22mm wide and is similar to a stick of gum.

What are RAID levels and their purposes?

RAID configurations like 0, 1, 5, and 10 provide different levels of data protection and performance through methods like striping and mirroring.

What does BIOS/UEFI refer to?

BIOS is the basic firmware that initializes hardware; UEFI is the updated version that offers faster boot and larger drive support.

How does Secure Boot enhance system security?

Secure Boot ensures only authorized operating system and driver versions are loaded, protecting against malicious code.

What is multithreading in CPU architecture?

Multithreading allows a CPU to run multiple threads of instructions simultaneously, enhancing performance.

What are the advantages of liquid cooling systems?

Liquid cooling is more effective at heat transfer than air cooling, making it suitable for high-performance computers.

Coaxial Cable

A cable with a single copper core contained within insulation, typically used for cable and satellite devices.

Twisted Pair Cable

A type of network cable made up of pairs of twisted copper wires used primarily for Ethernet.

Fiber Optic Cable

A cable made of flexible glass strands used for high-speed data transmission via light pulses.

RJ45 Connector

A standard connector used for twisted pair cables, commonly known as an Ethernet cable.

USB 3.0

A standard for universal serial bus with a maximum speed of 5 Gbps, known as SuperSpeed.

DVI

A digital visual interface cable designed to carry digital video signals.

SATA

Serial Advanced Technology Attachment, the most common type of drive interface for internal connections.

Plenum

A Teflon-type covering used for network cables that may be exposed to extreme heat.

T568A and T568B

Standards for color-coding twisted-pair wires in RJ-45 wiring connectors.

Error-Correcting Code (ECC) RAM

RAM that includes logic to detect and correct single-bit memory errors.

Single-mode Fiber

Fiber optic type that carries a single light path, typically sourced by a laser.

Multimode Fiber

Fiber optic type that carries multiple light paths, typically sourced by an LED.

Ethernet Cable

A twisted pair cable that uses RJ45 connectors for network communications.

Direct Burial Cable

STP cables that are suitable for burial underground and designed with waterproof sheathing.

HDMI

High-definition multimedia interface cable capable of transmitting digital audio and video.

Micro USB

The smallest USB connector type, commonly used for mobile devices.

Dual-Channel RAM

Memory configuration that coordinates two memory banks for synchronized data transfer.

GBPS

Gigabits per second, a unit of measurement for data transmission speed.

Cable Types

Categories describing different network cables, including coaxial, twisted pair, and fiber.

Storage Devices

Non-volatile devices designed for data storage, such as HDD and SSD.

Peripheral Cable

Cables used to connect peripherals, such as USB and serial cables.

VGA

Video Graphics Array cable, used as an analog video standard.

20/21 - File Transfer Protocol (FTP)

Used to manipulate files, remotely copy files, list and manipulate directories, and view file contents. Runs on ports 20 (data transfer) and 21 (file management). Not secure and transmits in plain text.

22 - Secure Shell (SSH)

A connection-oriented protocol that sets up secure Telnet connections for remote logins. Secure and runs on port 22.

25 - Simple Mail Transfer Protocol (SMTP)

Used to send email only and is a push protocol. SMTP uses port 25.

53 - Domain Name System (DNS)

Resolves hostnames to IP addresses and uses port 53.

67/68 - Dynamic Host Configuration Protocol (DHCP)

Dynamically assigns IP addresses to network clients, using port 67 for the server and port 68 for the client.

80 - Hypertext Transfer Protocol (HTTP)

Manages communication between a web server and a client for viewing internet content. Not secure and transmits in plain text on port 80.

110 - Post Office Protocol 3 (POP3)

Used for downloading email and operates over port 110.

137/139 - Network Basic Input/Output System (NetBIOS)

API for communication between computers over a network; operates on ports 137/139.

143 - Internet Message Access Protocol (IMAP)

Used for retrieving email messages.

161/162 - Simple Network Management Protocol (SNMP)

Used for network management. SNMP uses port 161 for requests and port 162 for receiving transmissions.

389 - Lightweight Directory Access Protocol (LDAP)

Used for accessing information stored in an information directory, operates on port 389.

443 - Hypertext Transfer Protocol Secure (HTTPS)

Secure version of HTTP, operates on port 443.

445 - Server Message Block (SMB) / Common Internet File System (CIFS)

Primarily a Microsoft protocol for shared file access, operates on port 445.

3389 - Remote Desktop Protocol

Allows remote connections to computers, operates on port 3389.

TCP - Transmission Control Protocol

A connection-oriented protocol considered reliable because the host acknowledges receipt of data.

UDP - User Datagram Protocol

A connectionless protocol where data is sent without assurance that it is received, making it faster but less reliable.

TFTP - Trivial File Transfer Protocol

A faster version of FTP that uses UDP instead of TCP, operates on port 69.

DHCP - Dynamic Host Configuration Protocol

Dynamically assigns IP configuration, operates on ports 67/68 using UDP.

Common Networking Hardware - Routers

Devices that connect multiple networking devices and determine optimal pathways using routing tables.

Common Networking Hardware - Switches

Layer 2 devices that examine packet headers and forward packets based on MAC addresses.

Common Networking Hardware - Access Points (APs)

Devices that allow wireless devices to connect to a wired network.

Common Networking Hardware - Firewalls

Security appliances that filter network traffic based on rules.

PoE - Power over Ethernet

Delivers power to devices over data lines, eliminating the need for separate power cords.

Hub

A layer 1 device that broadcasts incoming data to all connected devices.

DSL - Digital Subscriber Line

Provides connectivity via a telephone line.

NIC - Network Interface Card

Provides the physical interface between a computer and network cabling.

NFC - Near-Field Communication

A short-range wireless technology used for contactless payment.

IoT Devices - Internet of Things

Devices that connect to networks through a central controller, such as smart home devices.

IPv4

A 32-bit hierarchical address written in dotted-decimal notation, which identifies a host on a network.

Private Addresses

Addresses not routable on the Internet, with Class A ranges from 10.0.0.0 to 10.255.255.255.

What should you do before attempting a laptop repair?

Always check the manufacturer's documentation before attempting a repair.

What types of batteries are commonly used in laptops?

Laptop batteries are usually Nickel-cadmium (NiCd), Lithium ion (Li-ion), Nickel-metal hydride (NiMh), or Lithium-polymer (Li-poly).

How do you replace an external laptop battery?

Remove the battery pack and replace it.

How do you replace an internal laptop battery?

Remove the bottom cover, locate the battery, disconnect it from the motherboard, remove any screws, remove the old battery, insert the new battery, replace the screws and back cover.

What is the industry standard for RAM in laptops?

The industry standard for RAM in laptops is the smallest outline inline memory module (SODIMM).

What should you ensure when replacing a SODIMM?

Ensure that the new SODIMM is compatible with the motherboard.

What are the sizes of SSDs used in laptops?

SSD’s come in three sizes: 2.5”, 1.8”, and M.2.

How do you replace the SSD in a laptop?

Remove the bottom cover, locate the drive, remove any screws, disconnect the SATA cable, and replace the SSD.

What does a wireless network interface card (NIC) do?

It allows for wireless communication between the laptop and wireless access points.

What are common biometric features used for laptop security?

Facial recognition and fingerprint scanners.

What is Near-Field Communication (NFC)?

NFC is a wireless communication method that sends signals between compatible devices in close proximity, up to 10 cm.

What are the variants of Liquid Crystal Display (LCD)?

In-plane switching (IPS), Twisted nematic (TN), and Vertical Alignment (VA).

What are the advantages of OLED displays compared to LCDs?

OLED displays have less power consumption, a higher contrast ratio, and produce sharper images.

What components are included in mobile display components?

Backlight, inverter, screen, webcam, microphone, and WiFi antenna.

What types of USB connections are common?

USB types include USB-C, micro USB, or mini USB.

What are the steps to enable Bluetooth on a device?

Step 1: Enable Bluetooth; Step 2: Enable Pairing; Step 3: Find Device for Pairing; Step 4: Enter the Appropriate PIN Code; Step 5: Test Connectivity.

What does Global Positioning System (GPS) use for location determination?

GPS uses triangulation between receivers and satellites.

What is Mobile Device Management (MDM)?

MDM is a software package used to enroll corporate devices for oversight and security.

What is Two Factor Authentication (2FA)?

2FA increases device security by requiring an additional piece of information for access, such as a PIN from a token or authentication application.

What is a data cap?

A data cap is a limit placed on the amount of data that can be stored in a synchronization location such as the cloud.

What is cloud computing?

Cloud computing is the delivery of computing services over the internet, allowing users to access and store data and applications remotely.

What are some common examples of cloud computing?

Examples include online file storage services like Dropbox and iCloud, which allow users to store documents, photos, and videos.

What is a private cloud?

A private cloud is a cloud model where the virtualization resources are dedicated solely to a single user, ensuring greater security at a higher cost and less flexibility.

What is a public cloud?

A public cloud is a virtualized resource that is shared over the open internet, allowing multiple users to store their data in a common infrastructure.

What is a hybrid cloud?

A hybrid cloud combines both private and public clouds, offering security for sensitive data while providing the flexibility and scalability of public cloud resources.

What is Infrastructure as a Service (IaaS)?

IaaS is a cloud computing service that provides virtualized computing resources over the internet, allowing clients to build their entire infrastructure in the cloud.

What is Platform as a Service (PaaS)?

PaaS provides a platform for developers to build applications, handling the backend infrastructure while allowing developers to focus on application management.

What is metered utilization in cloud services?

Metered utilization refers to tracking and billing users only for the amount of cloud resources they actually use.

What is virtual desktop infrastructure (VDI)?

VDI is a technology that allows users to manage virtual desktops from a central location, replacing physical hardware with virtual hardware.

What is sandbox in virtualization?

A sandbox is a temporary, isolated virtual environment where data does not persist once the sandbox is terminated.