CompTIA IT Fundamentals (ITF+) FC0U61

Decimal

Base 10.

0-9.

How humans usually count/read.

Example: 1 or 32 or 56.

Binary

Base 2.

0 or 1.

How computers count/read.

Examples: 0 or 10 or 1001.

Hexadecimal

Base 16.

0-9 and A-F.

Used in memory addresses, color codes, and MAC addresses.

Examples: 26 or 2A or 49F or BB.

What are the 3 types of Numbering Systems?

Decimal.

Binary.

Hexadecimal.

What are the 2 well known Data Representation Systems?

ASCII and Unicode

ASCII

Is a data representation system called ASCII short for American Standard Code for Information Interchange.

128 Characters.

7 bit or 8 bit for extended encoding.

Unicode

Is a data representation system that includes ASCII.

Standard that represents letters of English, Arabic, Greek (and many more languages), mathematical symbols, historical scripts.

Boolean

A single value of either TRUE or FALSE

Basics of Computing and Processing.

input.

processing.

output.

storage.

Value of Data and Processing

Data and Processing are necessary for Digital products and Data-driven business decisions.

Digital products

e-books, downloadable music, internet radio, internet television and streaming etc...

Data-driven business decisions

Using facts, metrics and data to guide strategic business decisions that align with your goals, and initiatives.

Data capture and collection.

Data correlation.

Meaningful reporting.

intellectual property

Trademarks, Copyrights and Patents.

Trademark

Protects names, short slogans, or logos. Generally valid for 10 years and can be renewed every 10 years.

Copyright

Protects original works, such as art, literature or other created works. Generally valid for the years of the life of the author plus 80-100 years.

Patent

Protects new inventions, process and compositions of matter(such as medicines). Generally valid for 20 years.

Storage units

Bit(b).

Byte(B).

KB.

MB.

GB.

TB.

PB.

Bit

A contraction of "Binary Digit". A bit is the single unit of information in a computer, typically represented as a 0 or 1.

Byte

8 bits in every Byte

Kilobyte(KB)

1000 Bytes

Megabyte(MB)

1000 Kilobytes

Gigabyte(GB)

1000 Megabytes

Terabyte (TB)

1000 Gigabyte

Petabyte(PB)

1000 Terabytes

Throughput unit

How fast data travels.

bps

Bit per second.

Kbps

Kilobits per second.

Mbps

Megabits per second.

Gbps

Gigabits per second.

Tbps

Terabits per second.

Processing Speed

Frequency of electrical cycles per second. Measured in Hertz.

Mega Hertz (MHz)

Is a million electrical cycles per second.

Giga Hertz (GHz)

Is a billion electrical cycles per second or a thousand Mega Hertz.

Troubleshooting Methodology

1. Identify the problem.

2. Research knowledge base/ Internet if applicable.

3. Establish a theory of probable cause.

4. Test the theory to determine the cause.

5. Establish a plan of action to resolve the problem and identify potential effects.

6. Implement the solution or escalate as necessary.

7. Verify full system functionality and, if applicable, implement preventive measures.

9. Document findings/lessons learned, actions, and outcomes.

Troubleshooting methodology: 1. identify the problem.

Gather information.

Duplicate the problem, if possible.

Question users.

Identify symptoms.

Determine if anything has changed.

Approach multiple problems individually.

Troubleshooting methodology: 3 Establish a theory of probable cause.

Question the obvious.

Consider multiple approaches - Divide and conquer.

Troubleshooting methodology: 4 Test the theory to determine the cause.

Once the theory is confirmed(confirmed root cause), determine the next steps to resolve the problem.

If the theory is not confirmed establish a new theory or escalate.

Basic Networks

Wired(more predictable and reliable) and Wireless.

Basic wired network examples

Telephone connector (RJ-11) physically smaller than an Ethernet connector still widely used for DSL(Digital Subscriber Line) internet especially in rural areas .

Ethernet connector (RJ-45) usually used in data networking.

Basic wireless network examples

Bluetooth used for headphones, mouse which works 30ft or 9m away and widely used.

NFC(near field communication) used in mobile payments or payment with credit cards, needs to be within 10cm.

Peripheral devices

USB (Universal Serial Bus)

FireWire, Thunderbolt

Bluetooth

RF(Radio Frequency)

Graphic devices

VGA (Video Graphics Array)

HDMI (High Definition Media Interface)

DVI (Digital Visual Interface)

DP (Display Port)

MDP (Mini Display Port)

Other Devices

Printer (USB, [old] Parallel port)

Scanner - scans documents to create digital copy (USB)

keyboard (USB, Bluetooth, Infrared ,[old]PS2 connector)

Mouse (USB .[old]PS2 connector)

Camera (USB)

External hard drive (USB)

Speakers (USB, Speaker audio cable)

Display (HDMI,DVI,VGA,MDP,DP)

Installation Types

Plug-and-play vs Driver(software that tells the computer how to use the device corrrectly) installation and their required steps.

IP based peripherals.(are configured by connecting them to a network and assigning them an IP address)

Web-based configuration steps( involves accessing a device's settings through a web browser using its IP address. )

When doing Driver Based Installation

Should get driver from the manufacturer with the latest version.

IP based peripherals

Device that needed to be connected through the web interface.

CPU’s

ARM: no Intel or AMD processor, used for smaller devices(Mobile Phones, Tablet, Car, Webcam, Camera etc…).

32-bit: can only hold up to 4G of RAM(Laptop ,Workstation ,Server)

64-bit: can support a lot of RAM compared to a 32-bit processor, which is all modern processors(Laptop ,Workstation ,Server). need to ensure software is compatible with the processor to make full use of all the processing power of the machine.

GPU and Cooling

GPUs(or video card, graphics card, graphics adapter) are kept cool by 2 methods

[Air cooling]

• Open-Air Coolers: The most common type, featuring multiple fans on the GPU to directly cool the heatsink and disperse warm air into the case. 

• Blower Coolers: These are enclosed in a plastic housing and use a small centrifugal fan to draw cool air, pass it over the heatsink, and then exhaust the hot air directly out of the rear of the GPU and the computer case. 

[Liquid cooling]

Water or another liquid coolant absorbs heat from the GPU via a water block. The heated liquid is then pumped through tubes to a radiator, where fans blow air across the radiator's fins to dissipate the heat into the surrounding environment. 

Internal Computing Components

Motherboard contains the following components:

PSU:(Power supply unit) are connected to the motherboard, hard drives and fans.

Heatsink(usually with a fan over it) and the CPU lies underneath the Heatsink.

RAM stick which is used to store programs.

BIOS is a chip on the motherboard that stores computer settings(time and date, boot order, configuration on the processor etc…), it stored with a little battery(so if you change the settings but the computer keeps reverting settings to a previous date its time to change the battery, a healthy battery can last 10+ years).

The Motherboard is a big board that is inter-connect with all sort of components and also has a variety of expansion slots aka PCIe(PCI express).

All motherboard components won’t change they across time in one form or another they will always carry RAM, CPU, some kind of CMOS(chip that houses the BIOS) with its own BIOS(software), some kind of expansion slots, connectors for hard drives etc… Computer stores in a hard drive, hard drives are connected to the motherboard via SATA ports/connectors or solid state connectors. When you want to access a program it accesses data from the hard drive and runs it through the RAM chip which holds the data of programs you want to run then the RAM will send the program data to the processor where it is then processed to be used for a variety of uses from displaying an image by letting the processed data flow out through the display port which is connected to a display, or if a video card is present the processor will send some of the data to the video card which is then passed on to the display via the display port.

The reason for a RAM is because though the hard drive can hold a lot of data it is slow when trying to retrieve data from the hard drive, that is where RAM comes in where the data is preloaded for fast access to the program the user wants to run.

A chipset is like a “traffic controller“ that coordinates the flow of data between CPU, memory, storage and other peripheral devices.

Storage devices

Volatile Memory aka VM (such as RAM) means when the computer is off all data will be lost. Non-Volatile aka NVM is when the computer is turned off the data is still saved in the storage device such as ROM(read only memory) the physical hardware chip and the BIOS(Basic Input/Output System) which is the firmware(software) that contains the computer's initial startup instructions.

Hard Drive aka HDD(Hard Disk Drive) which is relatively cheap but is also slow compared to a Solid State Drive SSD which very fast because it has no moving parts unlike an HDD which has a spinning disk. for connections both HDD and SSD most commonly use SATA Cables or SATA Connectors for internal connections (connecting to the motherboard), which uses a single cable for both power and data, and USB for external connections. SSDs have two styles of form factors(the physical size, shape, and layout of a hardware device or component)

there is a SATA form factor and there is a NVMe(Non-Volatile Memory Express) which is the fastest option because it is connected directly to the CPU but needs a NVMe connector on the motherboard.

USB thumb drives aka USB flash drive or pen drive, is a small, portable storage device that uses flash memory to store data and connects to computers and other devices via a USB port.

NIC

NIC(Network Interface Card) allows the device to connect to a network be it wired(Ethernet) or wireless(WI-FI). Motherboards with a built in NIC it is called a ‘on board NIC card‘.

Laptops generally come with a wireless NIC card built in to the motherboard but most desktop don’t instead they have an ‘add on card‘ which needs a specialized slot for it to be built-in to the motherboard, alternatively a desktop can utilize a USB wireless NIC card.

Internet Connections

56k dialup internet:

requires a modem and uses the telephone system 1990s back in the really slow and is no longer used anymore.

Fiber Optic:

Uses cables made of thin glass or plastic to transmit data as light signals. Very fast within the hundreds megabits to gigabits. Has by far the fastest internet connection.

Cable: Uses cable TV.

Relatively faster then DSL . Relatively amongst cable providers.

DSL(Digital Subscriber Line) aka Broadband:

Uses the Telephone line. not as slow as dialup internet. It is within the megabit range.

Wireless:

• Radio aka Radio Frequency: Requires an antenna and both provider and client antenna must be facing each other.

• Satelite: Becoming popular despite being around for a while. Used in really rural areas. It works just as long as the antenna can see the sky. used to be slow but has gotten faster over the years.

• Cellular aka Cellular Wi-Fi: Come in 5G(within the gigabit range), 4G(within the megabit range) and 3G(within the megabit range) networks.

Network Storage

Local network storage types:

• NAS: NAS aka (Network Attached Storage) is a dedicated storage device(like a specialize computer )connected to a network that allows multiple users to store, access, and share files and data from a central location.

• File Server : Is a general purpose computer configured by software(like Linux or Windows) to perform file serving tasks, its used by businesses, because it offers greater customizability, scalability and powerful hardware for handling heavier workload than a NAS and running additional applications beyond just file storage.

Cloud Storage Service: Just means storing data on someone else’s network which are usually one of these three cloud providers (Amazon AWS, Google Cloud and Microsoft Azure Cloud) to name but a few.

Common Computing Devices

Mobile phones - Nowadays are handheld computers, general purpose computers with the ability to make a call.

Tablets - Giant mobile phones.

Laptops - Like desktop computers except smaller, portable, has a built-in screen and a bunch of connectors. probably not going to be as fast as a desktop unless its expensive.

Workstations -  Is a Desktop Computer generally with a specialized operating system.

Servers - Serves the data and processes the data to workstations in the network.

Gaming consoles - Are generally as powerful as the most powerful desktops available, high end computer at a pretty cheap price, they have powerful GPUs in them and have to display and process graphics very fast.

IoT Devices

IoT aka the Internet of Things. IoT devices is basically anything that can connect to the internet.

Home appliances

Home automation devices

• Thermostats

• Security systems

• Modern Cars

• IP cameras

• Streaming media devices

• Medical devices

Its great by allowing more connectivity and ease of use in life but with this comes a variety of complex technology(because of Wi-Fi or Bluetooth). But also brings a lot of security problems, cause if all devices can be accessed via internet it also means hackers can access said devices.

LAN vs WAN

LAN(Local Area Network) generally a network that is limited within a single building.

WAN(Wide Area Network) Spans the entire globe. such as the internet. Has basically no boundaries.

Basics of Packet Transmission

When data traverses over a network they are called Packets.

TCP(Transmission Control Protocol)/IP(Internet Protocol) are the rules used to communicate between computers around the world.

TCP/IP are known as a protocol stack.

IP is responsible for routing packets across the internet or network, which is also responsible for giving an IP address a logical address assigned to all host on the network.

TCP  makes sure when data is received by the machine it follows the standard and is able to read and detect errors which also helps find ways to fix it.

URL to IP addresses

Almost every single web server on the internet or a network has an IP address.

DNS(Domain Name System) - its a system that is used to translate a domain name (just the website itself rather than a specific page on the website) to an IP address.

URL(Uniform Resource Locator)-to-IP translation - Which means the user doesn’t need to know the IP address of the server that hosts the Website but instead just needs to know the URL of the website which not only will they get the IP address to server hosting the website but also can give detailed instructions such as what page on that particular website the user wants to access. URL-to-IP translation is done by giving the URL to the DNS which in turn gives back the IP address to the website.

Web and Mail Protocols

TCP/IP is not just two protocols it is a suite of protocols. the following are the basic protocols in the suite.

HTTP/S - (Hyper Text Transfer Protocol) 

used to transfer webpages from the web server to a computer, the HTTPS(the S stands for secure)variant is an encrypted version, where as the HTTP is none encrypted(that is vulnerable to hackers) which is the default webpage. this protocol is used to browse the internet.

The following protocols is used to receive emails:

POP3 (Post Office Protocol) - really old and just pulls everything from the web server.

IMAP (Internet Message Access Protocol) - is almost always used when setting up emails, since it allows synchronization which is good for keeping track of email across different devices.

a computer must be configured to use either POP3 or IMAP

SMTP (Simple Mail Transfer Protocol) - is the only protocol used when sending email.

Network Devices

Modem - Stands for modulator-demodulator. originally meant to convert digital to analogue and vice versa. But nowadays it means a device that enables devices to connect to the internet.

Router - Its used across the internet to connect to different networks. It manages and directs traffic of data packets and sends them to the right device. It creates a private local network such as a home Wi-Fi where devices can communicate and share resources. It also assigns unique IP addresses to each device on the private network, enabling them to identify and communicate effectively. In most home setups, the router also acts as a Wi-Fi access point, providing a wireless connection for your devices. It connects to dissimilar networks(WAN )

Switch - In a network it acts as the backbone of a local area network (LAN), connecting devices such as computers, printers, and servers. It learns the unique MAC addresses of the devices connected to its ports and builds a table to track them. When a device sends data, the switch uses the MAC address in the data packet to send it directly to the correct destination port. This process prevents unnecessary traffic, providing dedicated bandwidth and improving security compared to older hub devices, which would send data to every port. It allows computers to connect within the same network.

Access point - a wireless Access point is basically a switch, it computers to connect and communicate wirelessly.

Firewall - Used to protect the network from people trying to break in to the network.