CompTIA ITF+

A Local Area Network (LAN) is a group of computers or other network devices in the same location that can communicate with one another

A WAN is a Wide Area Network connecting two or more LANs over a larger geographical area using a device called a router.

Remotely accessed computer systems (RACS) are servers which give one access to online apps (e.g. Office Online). They enhance local capabilities.

Input/output devices are devices capable of sending data (output) to a computer and receiving data from a computer (input).

64-bit vs 32-bit

Passive cooling utilizes natural conduction, convection, and radiation to cool a component. The most common type uses a heat sink which is a block of heat-conductive metal such as aluminum affixed to a chip with some heat-conductive thermal paste. The heat sink has spikes or baffles that increase its surface area. Heat wicks away from the chip into the heat sink and dissipates into the air.

They help heat dissipate into air.

Random access memory holds all active programming on a computer including the OS and running applications and data. RAM only temporarily stores data. When you turn off the computer, all the data stored in RAM disappears.

The most common RAM size you can find in everyday laptop PCs nowadays is 8GB. Some lower-end models come with 4GB and in some cases only 2GB. Higher-end mainstream laptop models oftentimes feature 12GB and 16GB. You can find high-performance gaming laptops and mobile workstations with 24 or even 32 Gigabytes, too.

Alternating Current (AC)

A power supply unit (PSU) is a component found in desktop computers that handles the conversion from AC to DC.

Universal Serial Bus (USB)

For connecting external hard drives (not currently used much)

Pink for microphone, green for speakers, and black for other devices

USB Type B

USB 3.0

USB Mini B

USB Micro B

Firewire 400

The difference is in both the quality of the signal that they carry and the type of signals. VGA was standard for a long. DVI was an improvement. However, both only carry video signals. HDMI (high-definition multimedia interface), on the other hand, carries high-definition audio and video.

5 Gbps

A hard drive is a device for long term storage. When you power off the PC, the data on the hard drive stays put. It's available when you turn the PC back on. It'll be there until you delete it, or if you're unlucky, until the drive dies.

8 bits

1) It provides a user interface. 2) It provides coordination among hardware components. 3) It monitors health and functionality. 4) And it provides a way to store and retrieve data.

The Dock

72 degrees Fahrenheit or about 22 degrees Celsius with 50%

1) Start with hardware connectivity – connect power, monitor, keyboard and mouse 2) connect to the network 3) localization and user account setup connect to the network 4) update OS and security 5) uninstall programs and features to personalize

Uninterruptible power supply provides surge protection but also protects the computer from brownouts and blackouts.

An executable file

Via Control Panel or through uninstall routines

.zip, .rar, .tar

1) wired, 2) plugged the device into the wall Jack, 3) Wireless, that's Wi-Fi

The data transfer rate

1) Install printer drivers and assure good connectivity. 2) Devices and Printers | Printer Properties | Print a test page 3) Printer properties | Sharing | Share this printer

Spyware gathers information about system usage, as the name would suggest. Spyware generally installs as part of some otherwise benign program or media. Some spyware collects information about websites you visit or things you purchase. The more vicious kind like cloggers literally report the keystrokes you make.

Protecting against malware starts with keeping the operating system up to date. Both Windows and Mac OS do this automatically as long as the machine is connected to the Internet. The exam might ask about antivirus programs, treat these older applications like modern anti malware software, keep both the applications and definition files updated.

Long mix of cases, numbers and symbols

Adjust the energy usage with the power option applet in the Control Panel, adjust the screen brightness, set aggressive sleep options for moving parts like hard drives

Compressed air

Glass cleaner

Power and connectivity

Web search

A relational database interlink multiple tables

A primary key

A CSV file

Assembly language

Raw facts that are systems and processes generate and collect on a regular basis

Copyrights, trademarks, and patents

Copyright protection is automatically granted to the creator of a work once they create it

The owners of trademarks must register their marks with the government to achieve full protection in the US.

An inventor must demonstrate that their idea meets three criteria. First, it must be novel, meaning it's a new idea that nobody has thought of in the past. Second, it must be useful, meaning that it provides some benefit and then it's actually possible to use the invention. And third, it must be non-obvious, meaning that there was some inventive work involved.

When we store data on a magnetic hard drive, the computer divides that drive up into billions of tiny little spaces, each designed to store a single bit. If the value of the bit is one, the computer places a magnetic charge in the location used by that bit. If the value of the bit is zero, the computer leaves no magnetic charge in that location. When data is stored on a solid state, hard drive or in memory, the process works the same way, but it uses electric charges instead of magnetic charges. If the value of a bit in memory is one, there was a small electrical charge in that memory location.

Throughput which is the speed by which a network can transfer data in bits per second

Radio waves to transmit radio signal pulses

Capacity and bandwidth

CPUs have internal clocks that time, how quickly they can perform a single mathematical operation. Their internal clocks tick billions of times per second. We measure the speed of a CPU based on how fast that clock ticks, and we count those ticks using a unit called Hertz, where each hertz is a single tick.

Each digit can store 16 possible values, ranging from zero to 15. the values zero through nine to represent the numbers zero through nine, but then using the values A through F to represent 10 through 15.

an international encoding standard for use with different languages and scripts, by which each letter, digit, or symbol is assigned a unique numeric value that applies across different platforms and programs.

1) Integers are values that do not have decimal or fractional parts. 2) Floating point numbers or floats are numbers that do have decimal places associated with them. The precision of a floating-point number indicates how many decimal places may be used with that number.

Character strings consist of one or more characters strung together, such as in a word sentence or paragraph, and these character strings consume one byte per character.

Servers are powerful computers that carry out a dedicated function. Companies might use servers to share files internally, host a website, run a database or perform many other functions.

Industrial control systems, or ICS systems are the devices and systems that control industrial production and operations. These include systems that monitor electrical, gas, water and other utility infrastructure and production operations, as well as the systems that control sewage processing and control irrigation and other industrial processes.

The M1 processor

A 64-bit processor can manage 17 billion gigabytes of memory, which is far more memory than any computer will be using any time soon

When a computer starts up, it uses a very small operating system, called the unified extensible firmware interface or UEFI, that's stored on the motherboard to get the system up and running and load the full operating system from the hard drive. This task was once performed by the basic input output system called BIOS.

A network Interface Card is typically directly on the motherboard; they provide the ability to connect to both wired and wireless networks.

Plug and play

HDMI; able to carry both audio and video on the same wire and support high resolution video up to 5K an beyond

Displayport; offers high-resolution up to 5K and beyond

Volatile storage (temporary i.e., RAM) and non-volatile (permanent i.e., HDD)

The RJ-11 is smaller and only has six pins.

Near field communication or NFC technology allows extremely short-range wireless connections for two devices to communicate using NFC. They need to be no more than a couple of inches apart.

Cable internet connections use a modem to convert the digital signals of a computer network to the analog signals that travel on copper wires.

20 gigbits per second

They may use fixed wireless services. These services are point to point services that use radio frequency or RF communications. They could also use satellite internet connections.

IP is responsible for routing information over the network. IP is used both on the internet and on your local area. Network IP assigns each computer on the network its own address called an IP address. IP addresses uniquely identify computers on a network, and they are the way the computers identify each other. The internet protocol breaks up data sent into small pieces called packets, each packet is a few kilobytes of data. (The reason we break data up into packets like this is to make our networks more reliable. If we break that file up into thousands of smaller packets and one of those packets fails, we only need to transmit that one single small packet. Larger packets would also clog up our networks.) We can just send a large file and IP will handle breaking it up into packets and then putting those packets back together again on the other side.

Internet Protocol Addresses or IP Addresses

Those numbers may range between zero and two hundred and five-fifty because each number is represented by one byte, or eight binary bits (11111111)

First, you can assign an IP address statically. This means that you go into the system settings and manually specify its IP address. You'll be responsible for ensuring that you choose a unique address that fits within the allowable range for your network. Second, you can use the Dynamic Host Configuration Protocol, or DHCP allows you to configure a pool of IP addresses and then DHCP will automatically assign those addresses to systems as they join the network. Typically, servers are configured with static IP addresses, and end user devices are configured with dynamically changing IP addresses.

Hexadecimal notation

- First, no octet and an IP address should ever be larger than two hundred and fifty-five.
- Second, IP addresses, starting with the number one hundred and twenty-seven are reserved for use as loopback addresses. The most common loopback address is 127.0.0.1, and when it's used in communications, it's the equivalent of telling a system to talk to itself.
- The third rule is that the first number in an IP address should also never be higher than two hundred and twenty-three.
*Addresses with first numbers between 224 and 239 are called multicast addresses. They're used for sending messages to many systems at the same time, and they should never be assigned to an individual system.
*Addresses beginning with values between 240 and 255 are reserved for experimental use and again should not be found on individual systems.

- Every time you connect to a network, that network provide your computer with the IP address of a local DNS server that your computer can use to look up IP addresses for domain names.
- Then, whenever you type in the domain name of a web site into your browser, your computer sends a request to the local DNS server, asking it for the IP address associated with that name.
- If the server knows the answer to your question, it responds to the request with the IP address and then your web browser can go ahead and connect to the web site using that website's IP address.
- If you're a local DNS server doesn't know the answer to your question, it contacts other DNS servers to determine the correct answer and then it responds to you.

A router

The most common example of a firewall is a border firewall. These border firewalls sit between an organization's internal network and the internet. Any internet connections that aren't covered by a firewall rule are automatically blocked.

Wi-Fi is a set of standards governed by the Institute of Electrical and Electronics Engineers (IEEE), and it describes the technical details of how wireless devices can communicate with each other and with wireless access points.

Wireless access points or WAPs are used to connect wireless devices within home or business networks.

They are radio transmissions. And as such, they can be picked up by anyone with a suitable antenna and receiver.

When office conditions weaken radio signals, we call that situation attenuation. Attenuation limits the range of wireless networks.

In some cases, network administrators may wish to point a wireless signal in a specific direction, such as when they're creating a point-to-point network between buildings. This greatly increases the range of the network by focusing power in a single direction.

Conduct a site survey using specialized hardware and software to measure signal strength and provide optimal wireless signal coverage. These surveys often produce a heat map that graphically illustrates areas of strong coverage and those that require improvement. They may also identify areas where electromagnetic interference is causing disruptions to your wireless network. You can often improve your wireless coverage by adjusting the channels that you use in your building to avoid overlap with the channels used by other nearby businesses. Network engineers have the ability to manipulate the power levels transmitted by each access point to tweak coverage and prevent interference.

Pre-shared keys are the simplest kind of wireless authentication and are commonly used on home Wi-Fi networks. In the pre shared key approach, the network uses an encryption key to control access.

Captive portals provide authentication on unencrypted wireless networks. When a user connects to a network using a captive portal, they are redirected to a web page that requires them to authenticate before gaining access to the network.

Wi-Fi Protected Access or WPA is a Wi-Fi security protocol that replaced WEP in 2003. The first version, just called WPA, used the Temporal Key Integrity Protocol, or TKIP, to add security that WEP didn't have. TKIP changes the encryption key for each packet, preventing an attacker from discovering the key, even after monitoring the network for a long period of time.

Wi-Fi Protected Access 3, or WPA 3 is a Wi-Fi security protocol. As of 2020, new wireless devices are required to support the WPA three standard. WPA three also supports the CCMP protocol, but it adds a new technology called simultaneous authentication of equals, or SASE. SASE is a secure key exchange protocol that provides a more secure initial setup of encrypted wireless communications.

Hypertext Transfer Protocol or HTTP.

The Hypertext Transfer Protocol Secure, or HTTPS, adds encryption to web connections to prevent eavesdroppers from seeing what you're doing on a web site.

The Post Office Protocol 3 is an Internet protocol used by email clients to receive emails. It takes new messages that are waiting for you on the server and downloads them to your computer. Once they're downloaded, they're deleted from the server and you won't be able to download them again. Your email lives only on your computer.

Simple computer that has been optimized for establishing a remote connection with a server-based computing environment. Ex. Chrome books, which run Chrome OS

Windows and the many distributions of Linux

The file system is the technology that describes how the data is stored

That just means that we can put folders inside of other folders to help us organize our files.

We can set permissions on files to allow different users and groups of users the ability to read, write, delete and modify files.

Encryption is a technology that makes it impossible for someone to read a file unless they have the necessary decryption key.

The NTFS file system used by Microsoft is the most popular file system for the Windows operating system. NTFS provides compression, encryption and journaling.

The FAT32 file system is an older file system that used to be the standard for Windows systems (no encryption, compression or journaling, limit of 4GB file).

- the Mac OS extended file system, called HFS, was a simplistic file system created in the 1990s (no encryption, compression or journaling, limit of 2GB file).
- HFS Plus newer HFS Plus now supports encryption, compression and journaling. It also supports file sizes up to 60 and exabytes.
- The newer Apple file system, APFS was released in 2017, and it's a higher performance file system designed to work very well on solid state drives. APFS removed journaling to increase performance and replaced it with other crash protection technology. APFS supports encryption, but it doesn't provide native compression capabilities.

Executables in Linux don't require any specific extensions for those files to execute. Instead, Linux operating systems allow users to set an attribute on a file that indicates that the file is executable.

Drivers are software components that tell the operating system how to interact with a particular piece of hardware. Your operating system comes pre-installed with hundreds or thousands of commonly used drivers. These drivers allow you to set up many pieces of hardware with plug and play technology, where the hardware can easily start working without much, if any, configuration on your part.

Virtualization platforms involve the use of a host machine that actually has physical hardware. That hardware then hosts several or many virtual guest machines that run operating systems of their own. The host machine runs special software known as a hypervisor to manage those guest virtual machines. The hypervisor basically tricks each guest into thinking that it's running on its own hardware, when in reality, it's running on the shared hardware of the host machine. The operating system on each guest has no idea that it's virtualized. So software on the guest machine can function in the same way as it would on a physical server. This shared hardware platform makes it easy to shift memory storage and processing power to wherever it's needed at the time. Examples of virtualization platforms include VMware and Microsoft Hyper-V.

Productivity- Productivity software is the common software that we all use to get our work done on a daily basis.
Collaboration software- collaboration software is the software that allows us to interact with our teammates, customers and business partners on a regular basis. Business software- The third software category business software is the software that we used to run and manage our businesses.

Manually clear the cache. Deactive client-side scripting. Disable browser add-ons or extensions. If the user is on a network that requires the use of a proxy server, the proxy server settings will have to be configured. If someone travels to a network where the proxy server is not available, the proxy setting will have to be disabled.

Locally installed applications are 1-tiers applications. Client/server applications are 2-tier applications. Databased-driven applications are 3 tier. These models describe how many different servers are involved in presenting an application to end users. • The general term n-tier architecture describes this approach and can be any value that we require because we can have as many layers of servers as we need to get the job done.

Software purchased from a vendor. The vendor owns the software and charges for its use.

When you use interpreted code, the computer reads the actual instructions written by the developer as it executes the code. The computer does this using software called an interpreter that's designed to understand a specific language.

When executing compiled code, the programmer runs a tool called a compiler on their program to produce an executable file. This executable file contains instructions in machine language that carry out the programmer’s instructions. When a user wants to run the program, they launch the executable file rather than the programmers original source code. Examples of compiled languages include C and C++, Java, Go, Julia and Fortran.

A language that allows programmers to write code that works directly with the hardware bypassing the use of a compiled or interpreted language.

You can think of a database as a central repository for data that allows you to store your information and organize tables so that many people can access it at the same time.

Queries are simply questions that users ask of the database. They're written in a special programming language called the structured query language (SQL).

Each column in a table is called a field, and each field contains information about a single characteristic of the subject.

A key is our special purpose database field that plays an important role in the relational model. They help to organize the information in tables and to define the relationships between those tables.

A foreign key defines the relationships between tables. The primary key in a table when in another table is called a foreign key.

CREATE creates a new table. ALTER modifies a table. DROP deletes a table.

SELECT retrieves data. INSERT adds data. UPDATE changes data. DELETE removes data.

Confidentiality of information, the integrity of information and the availability of information

Snooping, dumpster diving, eavesdropping, wiretapping and social engineering.

Integrity means that we don't allow any unauthorized changes to information

The unauthorized modification of information occurs when an attacker gains access to a system and makes changes that violate a security policy. Organizations should consider the permissions that each employee needs to perform their jobs and then limit employees to the smallest set of permissions possible (principle of least privilege)

A man in the middle or MITM attack, the attacker intercepts network traffic as a user is logging into a system and then pretends to be that user. The attacker might be able to steal user's password and then use it later to log into the system themselves. The best way to address a man-in-the-middle attack is the use of encryption to protect communications.

Availability controls ensure that information and systems remain available to authorized users when they need them. These controls protect against disruptions to normal system operation or data availability.

Denial of service or DoS Attacks occur when a malicious individual bombards the system with an overwhelming amount of traffic. The idea is to simply send so many requests to a server that the server is unable to answer any requests that come from legitimate users. We can protect our systems against these denial of service attacks by using firewalls that block illegitimate requests and by partnering with our internet service providers to block those attacks before they even reach our networks.

Servers, hard drives, network gear and other equipment all fail occasionally, and those failures can disrupt our access to information, making it an availability problem. We could protect against hardware failures by building systems that have built in redundancy so that if one component fails, another is ready to pick up the slack.

Host firewalls block unwanted inbound connections from elsewhere on the network. The firewalls do this by restricting the systems and ports that may communicate with our devices.

Validate that the software came from a legitimate source.

If you download software from any source other than the original equipment manufacturer, the OEM, then it's possible that a third party modified that software and created a security vulnerability. The more software packages you have installed on the system, the greater the possibility that the system will have some serious security flaws.

No, your employer owns that equipment and is normally legally entitled to monitor your use of their systems.

Security policies are the bedrock documents that provide the foundation for an organization's information security program. Compliance with policies is mandatory, and policies are often approved the very highest levels of the organization

Guidelines are where security professionals provide advice to the rest of the organization, including best practices for information security.

1) Identification 2) Authentication 3) Authorization

Password expiration and password history to avoid reusing the same password

1) something you know 2) something you are and 3) something you have

In multifactor authentication, the techniques must be different factors (something you know, something you are, and something you have)

First, least privilege minimizes the potential damage from an insider attack. Second least privilege limits the ability of an external attacker to quickly gain privileged access when compromising an employee's account unless they happen to compromise a system administrators account.

The operating system itself restricts the permissions that may be granted to users and processors on system resources. Users themselves can't modify any permissions. Mac is normally implemented as a rule based access control system, where users and resources have labels and the operating system makes access control decisions by comparing those labels.

Role based access control (RBAC) system simplifies some of the work of managing authorizations. Instead of trying to manage all of the permissions for every individual user, administrators create job-based roles and then assign permissions to those roles. Then they can assign users to the roles based on their jobs. Similarly, when a group of users needs a new permission, the administrator doesn't need to apply that permission to each individual user. Instead, they can apply the permission to the role, and all the users with that role will then receive the permission automatically.

Privileged account management

Service accounts are a special type of account used internally by a system to run a process or perform other actions.

Data at rest and date in transit

Digital signatures use encryption technology to provide non-repudiation for electronic documents. You might use biometric security controls, such as a fingerprint or facial recognition to prove that someone was in a facility or performed an action. You might also use video surveillance for that same purpose.

Redundancy and replication

Redundant arrays of inexpensive disks (RAID), technology places multiple hard drives in a single server and then stores copies of data in multiple locations on those drives. This protects the system so that no data is lost, even if one of the hard drives fails.