Comptia A+

-Responsible for defining the frequency the processor will use to execute a task.
-The higher the frequency in hertz, the lower the execution time of a task.
-Named "clock" due to its rhythmic pulse and ensures CPU and other components are working in sync.

-Auxiliary (supplementary) memory of the processor where the most accessed data that will be processed is identified and then stored.
-Executes faster than RAM because it is more readily available.

-Smallest and fastest cache level located directly within the CPU core(s).
-Usually split into two parts: one for data (D-cache) and one for instructions (I-cache).
-The first place the processor looks for information.

-Larger, slower than L1 cache, still faster than RAM.
-L2 cache is typically located either on the CPU die or close to the CPU.
-It serves as an intermediate cache, providing data that may not fit in the smaller L1 cache but is still frequently needed.

-Largest, usually shared among multiple cores.
-Slower than L1 and L2, but still faster than RAM.
-Helps reduces access times for data needed across different cores, ensuring smoother performance in multi-core systems.

-Manipulation of data: Performing calculations, sorting lists, and modifying documents/pictures according to user instructions.

-Can be volatile and nonvolatile. Examples include the ROM, RAM, PROM, EPROM, EEPROM, etc...

-Nonvolatile only. Examples include the HDD, FDD, DVD, Pendrive, SSD, etc...

-Converts AC > DC power from an external source
-Regulates and distributes DC output voltage throughout system.
-Usually most efficient at 50% load or volts.

-Uses switching regulators to convert power efficiently.
-Makes designing for multiple voltage inputs easier meaning most PSUs can operate in different countries.

-Connects computers, routers, and switches.
-Excessively long or low quality cables does not provide a good signal.
-Designed to perform various duties in specific environments.
-Support one or more industry standards including category 5, 6, etc...
-Two forms: Solid ethernet cables for better performance, and stranded ethernet cables that are more durable for travel.

-Alternative to PSU, Electrical power can be carried with a network cable without being tethered to an electrical outlet.

-As backup or sharing power between PSUs.

-Enables computer to run for a limited duration during power loss.

-Online: Ensures quality of power remains constant.
-Offline: Starts running after power loss, slightly delayed start-up time.
-Line-interactive: Combination of online and offline, provides more power protection.

-Uses heatsync with a fixed fan to cover the maximum surface area of the CPU to remove heat.
-Fan pushes air to the heat sync and the hot air in the sync expands and the heat gets pushed outside by case cooling.

-Uses water and a radiator to remove heat quietly.

-Read Only Memory (ROM).

-Electronic component that controls flow of current.
-Can act as a switch, or an amplifier (increasing signal strength).
-Made of semiconductor materials like silicon.

-Passive electronic component that stores electrical energy in an electric field.
-Made up of two conductive plates separated by an insulating material called a dielectric.
-Discharge the electrical energy when current is removed.

-Measure of capacitor's ability to store electrical energy measured in Farads (F).
-One F = amount of capacitance required to store one Coulomb of charge at one Volt.
-Typically have capacitance values in the range of Microfarads (µF), Nanofarads (nF), or Picofarads (pF).

-When voltage is applied, electric charge accumulates on its plates (positive and negative charge).
-Amount of electric charge a capacitor can store is directly proportional to its capacitance.

-In PSU power supply circuits, filtering capacitors are used to Smooth the ouptut from a rectifier (converts AC to DC) and eliminate ripples caused by conversion process.
-Act as Filters by smoothing out voltage fluctuations, providing steady DC output.
-Necessary to power motherboard, hard drives, and graphics cards.

-DRAM stores data in capacitors, which hold electric charges as 1s (charged, high voltage) and 0s (discharged, low voltage).
-Leaks charge over time, requires periodic refreshing.

-Data is read from capacitor and rewritten continuously back to the same location, which restores the electrical charge to ensure data preservation.
-DRAM Memory Controllers are responsible for sending refresh commands to DRAM chips.

-In digital circuits, capacitors used for decoupling to isolate different parts of the system from each other and prevent noise from affecting operation of sensitive components.
-Placed close to power supply pins of components like microprocessors and memory to filter out noise that might cause instability or errors.
-Act as local energy reservoirs, providing quick bursts of energy to components that require it and preventing voltage dips caused by sudden changes in current demand.

-Relatively high capacitance and are often used in PSUs for bulk energy storage and smoothing.
-Used in PSU circuits and audio applications for their high capacitance values.
-Polarized: Must be connected in the correct direction in the circuit, with the negative lead connected to the lower potential.

-Smaller, non-polarized capacitors with low capacitance values.
-Used for high-frequency filtering and decoupling. Also used in signal processing and timing circuits.
-Low cost, small, & widely available. However, performance varies with temperature and voltage changes.

-Known for stable performance and compact size, offers higher capacitance density compared to ceramic capacitors.
-Used in motherboards, memory circuits and power regulation circuits.
-Polarized: Like electrolytic, must be connected in correct orientation.

-Conducts electricity, but not as well as metals, to control electrical current.

-Circuit configuration where two inverters are connected to each other to form a feedback loop, creating a bistable state.
-Allows to store a bit of data (0/1) reliably.
-Essential for data retention in SRAM.

-Static Random-Access Memory (SRAM)
-Does not require refreshing.

-Static Random-Access Memory (SRAM)

-Static Random-Access Memory (SRAM)

-Static Random-Access Memory (SRAM)

-Dynamic Random-Access Memory (Specifically Synchronous Dynamic RAM)

-Dynamic Random-Access Memory (DRAM)

-Dynamic Random-Access Memory (DRAM)

-Static Random-Access Memory (SRAM)

-Static Random-Access Memory (SRAM)

-Dynamic Random-Access Memory (DRAM)

-Dynamic Random-Access Memory (DRAM)

-A type of non-volatile primary memory that aids in storing and retrieving information.
-Allows memory to be read only, mainly used for firmware purposes.

-A memory chip that can be programmed once after creation.
-Memory is permanent, cannot be erased/deleted.

-Programmable Read Only Memory (PROM)

Wen Tsing Chow (1956)

-EPROM (UV Light)
-EEPROM (Electrical Voltage)

-Dov Frohman (1971)

-Erasable Programmable Read Only Memory (EPROM)

-Electrically Erasable Programmable Read Only Memory (EEPROM)

-George Perlegos (1978)

-A developed version of EEPROM commonly found in USB drives, iPods, MP3, etc...

-Flash Memory

-Flash Memory

-Magnetic Storage Device

-Magnetic Storage Device

-Magnetic Storage Device

-Magnetic Storage Device

-Optical Storage Device

-A dedicated stand-alone device installed as part of a local area network (LAN).

-Cloud Storage

-Cloud Storage

-Cloud Storage

-Cloud Storage

1. Fetch: CPU receives instructions from memory, interprets them, and directs the next operation.

2. Decode: All instructions/commands translated into assembly instructions. The CPU decodes assembly code into binary instructions.

3. Execute: CPU executes instructions through calculations and technical algorithms and outputs processed data.

4. Store: After executing instructions, CPU stores output data into memory.

-The connector between CPU processor and motherboard. Used to ensure correct circuit chip insertion.

-Allows for easy swapping of the server CPU and prevents damage from insertion and removal.

-A unit within the CPU that can independently execute instructions.

-Set of instructions/code for the execution of concurrent programming in a CPU core.
-It is the smallest unit of execution within a program corresponding to a single line of execution within the CPU.

-Allows one or more cores to execute multiple threads at the same time.

-Refers to the ability of a CPU to run multiple threads in parallel, using one or more cores.

-Defines the set of instructions that the processor can execute.
-Acts as the interface between software and hardware, providing commands the software uses to perform operations, and translating them into low-level machine code that the hardware can understand.

-Refers to a family of instruction set architectures (ISA) used in Intel/Intel-compatible CPUs.
-"x86" name came from the Intel 8606 processor.

-Large set of instructions that can perform multiple operations in one instruction cycle.
-Reduces the number of instructions per program, saving memory and execution time for complex tasks.
-Slower clock speeds, consumes more power, generates more heat.
-Requires more transistors.

-Smaller and simpler than CISC, each instruction does one simple task.
-Designed for speed and efficiency.
-Requires more memory and more instructions to complete complex tasks.

-Server with multiple CPUs or cores processing simultaneously.
-Divides complex tasks into smaller sub-tasks that can be processed in parallel.

-CPU architecture designed to execute multiple instructions in a single CPU cycle.
-Groups multiple instructions into a single larger instruction.
-Primarily used for applications requiring significant parallel processing.

-Renders GUIs into visually attractive icons.
-Designed to rapidly manipulate and alter memory to accelerate creation of images in a frame buffer.
-Can be on video card, motherboard, and sometimes CPU die.

-AKA Mainboard, Base Board, System Board, Logic Board.
-Biggest board in a computer chassis.
-Allows communication between CPU, RAM, and all other hardware.

-Used to provide network connections.
-Transmits signals at the physical layer and deliver data packets at the network layer.
-Middle man between server and data network.

-Ethernet NIC: Computer-Network connection via Ethernet cable (RJ45 Connector).
-Supports different speeds 10/100/1000 mbps or higher.
-Common Ethernet Standards include 802.3 (wired ethernet) and 802.11 (wireless ethernet).

-Wi-fi connection.
-802.11a/n/ac/ax, with 802.11ac and 802.11ax (Wi-Fi 6) being the latest standard.
-Can be built into device or external as a USB adapter.

-Allows simultaneous sending and receiving of data.

-Allows data to be sent or received at one time, but not both at once.

-Feature that allows NIC to receive a "magic pocket" from the network to power up the computer remotely.

-Allows NIC to detect the best possible connection speed and mode with the network.

-Controller: "Mini CPU" directly decides the performance of network adapter.
-Boot ROM Socket: Enables boot ROM capability.
-NIC Port for Cable/Transceiver: Usually connects with ethernet cable or transceiver directly, which generates and receives electronic signals that are put on the network/fiber cable.
-Bus Interface: Serves for the connection between the NIC and computer/server via plugged into their expansion slot.
-LED Indicators: Helps users I.D. the working status of a network card whether the network is connected and data transmitted.
-Profile Bracket: Either full-height 12cm bracket or low-profile 8cm bracket, helps users fix the NIC in the expansion slot of a computer/server.

-Giant network of connected things and people that collects and shares data of how the devices are used and the environment around them.
-First example: Internet connected vending machines in the 80s-90s.
-Gathers data, processes and analyzes data, and returns instructions to the device.

-Short-range, low-power, low-cost.
-Bluetooth Low-Energy Protocol (BLE)
-Not designed for transferring large files.

-Standard: 802.11, allows transfer of hundreds of megabits in one second.
-Uses radio waves such as 2.4 or 5GHz. Both frequencies have a number of channels through which wireless devices can work to prevent overflow.
-Fast data transfer speeds for large amounts of data.

-Usually operates at 2.4GHz
-Low power consumption, low throughputs, 100m range.
-Resistant to communication errors and unauthorized reading.

-Simple, lightweight, short-range, low-power consumption, & low-cost.
-Designed for unreliable communication networks.

-For HTTP-based IoT systems.
-Relies on User Datagram Protocol (UDP) for establishing communication between endpoints. Able to transmit data to multiple hosts while retaining communication speed and low-bandwidth usage.

-GSM, 3G, 4G, & 5G.
-Send or transfer high amounts of data.
-High cost and high power consumption.
-Used in street lights, parking meters, hospitals, and industrial apps.

-Extraordinary speed, bandwidth, power efficiency.
-Launched in 42 countries.
-Billions of connected devices.
-Self-driving vehicles, smart grids for renewable energy, AI-enabled robots.

-Lack ability to be patched.
-Giant botnets.
-DDoS attacks.
-90% of consumers lack confidence.
-98% of all IoT device traffic is not encrypted.

1. Update: Keep all systems updated.
2. Lock Down Access: MFA, Risk-Based authentication, least privelege, & other best practices.
3. Don't Go It Alone: Enterprises can benefit by looking to external partners for help.
4. Deepen Your Defenses: No longer enough to secure perimeter or endpoint devices. Multiple defensive systems required like isolating IoT devices on a separate part of a network.

-Conventional computer and television screens have used this for decades.

-Flat, thin display device that mostly replaced CRT.
-Higher picture quality & handles higher resolutions.

-Type of LCD that controls image production.
-Uses transistors to adjust brightness of RGB subpixels.

-Differentiates from LCD with backlighting.

-Widely utilized in rear-projection television and front projectors for businesses and classrooms.

-Comparable to LCD and LED, flat, thin, sometimes wall-mounted.

-Converts electrical signals to soundwaves.
-Consists of coil, magnet and diaphragm parts.
-In-ear headphones use 8-15mm drivers, larger over-ear cups use 40mm drivers.
-Bass & treble become more clear with larger drivers.

-Electrodynamic.
-Magnetostatic.
-Electrostatic.
-Electromagnetic.

-Synchronizes location, speed, and time data for travel through satellites, a receiver, and algorithms.
-Three satellites required, a fourth satellite often used to verify information from the other satellites.
-Fourth satellite allows to calculate altitude of device.
-Made of three segments to provide location information: Satellites, Ground Control, and User Equipment.

-Used by GPS to determine position by measuring distances to three or more satellites.
-Measures time it takes for the signal from each satellite to reach the receiver (time delay), receiver can calculate distance to each satellite to determine exact location.

-Measures angles between receiver and two or more points (satellites, towers or landmarks).

-Cores are made of glass (sometimes plastic) where the light signal is set.
-Acrylic coating is applied to the cores in various colors and are placed in loose and tight tubes reinforced with glass, fiber, and kevlar along with a protective sheath.
-Use light signals instead of electrical to send data.
-Optical fiber elements typically coated with plastic layers & contained in a protective tube.
-Indoor and outdoor uses as well as underground and overhead.