CompTIA Exam Prep - ITF+, A+, Network+, Security+, CySA+

 Legal Hold A legal hold, or litigation hold, is a process used to preserve all forms of relevant information when litigation or an investigation is anticipated. It ensures that potentially important data is not altered, deleted, or destroyed, which could otherwise lead to legal consequences. Here's a detailed explanation: 1. What is a Legal Hold? A legal hold is a directive issued by an organization to its employees or custodians (individuals responsible for specific data) to retain and preserve information that may be relevant to a legal case. This includes both electronically stored information (ESI) and physical documents. Legal holds are a critical part of the eDiscovery process, which involves identifying, collecting, and producing evidence in legal proceedings. 2. When is a Legal Hold Triggered? A legal hold is typically initiated when: Litigation is reasonably anticipated. A formal complaint or lawsuit is filed. An internal investigation or regulatory inquiry begins. The or...

 Dark Web The dark web is a hidden part of the internet not indexed by standard search engines like Google or Bing. It exists within the deep web, which includes all online content not accessible through traditional search engines, such as private databases, subscription services, and password-protected sites. However, the dark web is distinct because it requires specialized software, configurations, or authorization to access, and it is designed to provide anonymity to its users. 1. How the Dark Web Works The dark web operates on overlay networks , which are built on top of the regular internet but require specific tools to access. The most common tool is the Tor (The Onion Router) browser , which uses layered encryption to anonymize users' identities and locations. Other networks include I2P (Invisible Internet Project) and Freenet . When using these tools, data is routed through multiple servers (or nodes), each adding a layer of encryption. This process makes it nearly impossi...

 SASE (Secure Access Service Edge) Secure Access Service Edge (SASE) is a modern framework that combines networking and security services into a single, cloud-delivered solution. It was first introduced by Gartner in 2019 to address the challenges of traditional network and security architectures, especially in the era of remote work and cloud-based applications. Here's a detailed breakdown: 1. What is SASE? SASE (pronounced "sassy") integrates networking capabilities like SD-WAN (Software-Defined Wide Area Network) with security functions s uch as Zero Trust Network Access (ZTNA), Secure Web Gateway (SWG), Cloud Access Security Broker (CASB), and Firewall-as-a-Service (FWaaS). This convergence allows organizations to provide secure and seamless access to users, applications, and data, regardless of location. 2. How SASE Works SASE shifts traditional security and networking functions from on-premises data centers to the cloud. Here's how it operates: Cloud-Native Arc...

 Race Condition A race condition is a situation in computing where the behavior of a program or system depends on the timing or sequence of uncontrollable events. It occurs when multiple threads or processes attempt to access and manipulate shared resources simultaneously, leading to unpredictable outcomes. Here's a detailed explanation: 1. What is a Race Condition? A race condition occurs in concurrent programming when two or more threads or processes "race" to access or modify shared data. The outcome depends on the order in which the operations are executed, which is often non-deterministic due to thread scheduling. This can result in inconsistent or incorrect data processing. 2. How Race Conditions Occur Race conditions typically occur in multi-threaded or multi-process environments. For example: Two threads attempt to update the same variable simultaneously. A thread reads a value while another modifies it, leading to unexpected results. A common scenario is the c...

 Watering Hole Attack A watering hole attack is a cybersecurity threat where attackers target a website or online platform frequently visited by a specific group of users, such as employees of a particular company or community members. The goal is to infect these websites with malicious code so that anyone who visits them unknowingly downloads malware or is exposed to exploitation. The term "watering hole" comes from the analogy of predators lurking near a water source, waiting to ambush their prey. How It Works: Profiling Targets:  Attackers first gather intelligence on their intended victims. They analyze their behavior, browsing habits, and frequently visited sites by observing social media activity, phishing, or monitoring web traffic. Compromising a Website:  Once attackers identify a popular and trusted website, they look for vulnerabilities. Common weaknesses include outdated software, plugins, or poor security configurations. Injecting Malicious Code:  After...

 theHarvester TheHarvester is an open-source cybersecurity tool primarily used for information gathering during the reconnaissance phase of penetration testing, where it efficiently collects publicly available data like email addresses, subdomains, and IP addresses about a target organization by searching through various online sources like search engines and social media platforms, allowing security professionals to identify potential vulnerabilities and areas for further investigation; it's often included in penetration testing distributions like Kali Linux due to its ease of use and effectiveness in the initial stages of a security assessment. Function: Collects publicly available information about a target organization, including email addresses, subdomains, and IP addresses Data sources: Searches through public sources like search engines (Google, Bing), social media platforms (LinkedIn), and online databases Strengths: Particularly effective at gathering email add...

 Pretexting Pretexting is a form of social engineering where attackers create a fabricated story or scenario to trick a victim into divulging sensitive information by building trust through a convincing, personalized narrative, often impersonating someone familiar to the victim, like a coworker or government official, to gain access to confidential data, which is considered illegal for financial institutions under the Gramm-Leach-Bliley Act (GLBA) when used to collect personal financial details. Deceptive scenario: Attackers craft a believable, tailored story to manipulate the victim into providing information they wouldn't usually share. Trust building: Unlike phishing, which relies on fear and urgency, pretexting aims to establish a false sense of trust with the victim. Targeted approach: Pretexting attacks often focus on specific individuals or organizations, gathering background information to craft a convincing narrative. Impersonation tactics: Attackers may im...

 GRE (Generic Routing Encapsulation) Generic Routing Encapsulation (GRE) is a protocol that allows data packets to be transported over a network by wrapping one packet inside another: How it works GRE encapsulates a payload packet inside a GRE packet, which is then encapsulated in a transport protocol like IP. The packet is then redirected to an intermediary host, where it is de-encapsulated and routed to its final destination. Benefits GRE can simplify connections between separate networks and enable the use of protocols that are not normally supported by a network. Limitations GRE tunnels are stateless, meaning the tunnel's endpoint has no information about the far end. GRE also adds two headers to the packet, which could violate maximum transmission unit (MTU) rules. Use cases GRE tunnels are ideal for forwarding internet-bound traffic from a corporate network to a service. GRE is similar to a VPN, but without encryption. It can be used to bypass open filtering...

 Smishing (SMS / Text Message) A smishing attack is a cyber attack that uses text messages to trick people into taking actions that are harmful to them, such as sharing personal information or downloading malware. The term "smishing" is a combination of the words "SMS" (short message service) and "phishing". Here are some examples of smishing attacks: Fraud alerts A text message that appears to be from a bank or other financial institution asking for personal information or to verify a transaction Package delivery A text message that claims a package was missed or delivered incorrectly, and includes a link to a fake survey Prize or lottery A text message that claims the victim has won a prize, and asks them to provide personal information or click a link to claim it Tech support A text message that warns the victim of a problem with their device or account, and asks them to contact a tech support number Smishing attacks can be difficult...

 Vishing "Vishing" is a term used for "voice phishing," a type of cybercrime in which attackers use phone calls to trick victims into revealing sensitive personal information, like credit card numbers or login details, by pretending to be a legitimate company or authority figure over the phone; essentially, it's phishing conducted through voice calls instead of email. Method: Attackers often use caller ID spoofing to make it appear that they are calling from a trusted source, such as a bank or credit card company. Goal: To obtain sensitive information from the victim by using deceptive tactics and social engineering. Example scenario: A scammer might call, claiming to be from a bank's fraud department, and ask the victim for credit card details to "verify" a suspicious activity.

 Ifconfig (Linux) ifconfig (short for interface configuration) is a command-line utility used in Unix-like operating systems, including Linux, macOS, and BSD, to configure, control, and query network interface parameters. Here are some key points about ifconfig: Functionality: It allows users to set IP addresses, subnet masks, and enable or disable network interfaces. It can also be used to view the current configuration of network interfaces. Usage: Common commands include ifconfig to display all active interfaces, ifconfig [interface] up to enable an interface, and ifconfig [interface] down to disable an interface. Deprecation: In many modern Linux distributions, ifconfig has been deprecated in favor of the ip command from the iproute2 package, which offers more features and better support for modern networking needs.

 Incremental vs. Differential Backups The main difference between incremental and differential backups lies in what data they back up and how they handle changes: Incremental Backup What it Backs Up: only the data that has changed since the last backup (whether full or incremental). Backup Speed: Generally faster because it only backs up the most recent changes. Storage Space: Requires less storage space since each backup contains only the changes made since the last backup. The restore process is slower and more complex. It requires the last full backup and all subsequent incremental backups to restore the data. Differential Backup What it Backs Up: All the data has changed since the last full backup. Backup Speed: Slower than incremental backups because it backs up more data each time. Storage Space: Requires more storage space over time as each differential backup grows larger until the next full backup. Restore Process: This process is faster and simpler, as...

 Regionally Diverse Backups Regionally diverse backups, also known as geo-redundant backups, are used to protect data and ensure business continuity in the event of a disaster: Disaster recovery By storing data in multiple regions, backups can be used to recover from a disaster and reduce downtime. Compliance Backups can be stored in different geographical locations to meet compliance requirements. Data migration Regionally diverse backups can migrate data from one region to another. Resiliency Backups in multiple regions can help ensure that workloads can continue to run even if one region experiences an outage. Some examples of regionally diverse backups include: AWS Backup: Allows customers to copy backups across multiple services to different regions.

 NFC (Near Field Communication) NFC stands for Near Field Communication, a short-range wireless technology that allows devices to exchange information when they are a few centimeters apart. NFC is used in a variety of ways, including: Contactless payments: NFC-enabled credit cards or mobile wallets can wirelessly communicate with a payment terminal to send encrypted payment information. Data exchange: NFC can be used to share small amounts of data, such as photos, music, or videos, between two devices. Connecting to devices: NFC can be used to connect to wireless devices, such as connecting a toy to a video game. Tracking inventory: NFC can be used to track inventory by scanning products. Accessing coupons: NFC can be used to access coupons by scanning in-store signs. NFC is more power-efficient than Bluetooth and is best suited for applications where devices need to be in close proximity. To check if your device has NFC capabilities, you can look at the backplate of ...

 APT (Advanced Package Tool) APT, or Advanced Package Tool, is a package management system used in Debian-based Linux distributions like Ubuntu, Debian, and Linux Mint. It simplifies the process of installing, updating, and removing software packages. Here are some key points about APT: F unctionality: APT is a front-end to the lower-level dpkg package manager, handling .deb packages. It can automatically resolve dependencies, ensuring that all required packages are installed. Repositories: APT uses repositories, which are directories that store collections of software packages. These repositories can be local or remote and are accessed over a network. Commands: Common APT commands include apt update (to update the package list), apt upgrade (to upgrade all installed packages), apt install (to install new packages), and apt remove (to remove packages). APT is a powerful tool that makes managing software on Linux systems straightforward and efficient.

 yum (Yellowdog Updater, Modified) YUM, or Yellowdog Updater, Modified, is a free, open-source tool that manages software packages for Linux systems: What it does YUM can install, update, remove, and query RPM software packages from official and third-party repositories. It can also automatically resolve dependencies during installation. How it works YUM is a front-end for the RPM package manager. It stores packages in software repositories or repos. Repos can be local or remote, and users can access them over a network connection. How to use it YUM has a command-line interface, but other tools provide graphical user interfaces. For example, to update all packages in the system, you can run the command yum update. To update only security-related packages, you can run the command yum update --security. History YUM was originally a rewrite of Yellowdog UPdater (YUP), a software updater for Yellow Dog Linux. A newer version of YUM called Dandified YUM (DNF) has replace...

 Adware Adware is malware that displays advertisements on a computer or device without the user's knowledge or consent. Adware can also collect information about a user's browsing habits and online behavior to target them with customized ads. Adware can be installed unknowingly when a user is trying to install legitimate applications with which adware is bundled. It can also be downloaded through mobile apps or by downloading freeware like toolbars, HD wallpapers, or widgets. Some signs of adware include: Advertisements appearing in places they shouldn't be The web browser's homepage changing without permission Web pages not displaying properly Website links redirecting to different sites The web browser slowing down New toolbars, extensions, or plugins appearing in the browser To prevent adware, you can use antivirus software or regularly update your device. Antivirus software can detect malware before it infects the rest of your device.

Microsoft Remote Assistance Microsoft Remote Assistance (MSRA) is a feature in Windows that allows a user to get help from another user over a network or the internet. It lets a trusted person control a user's PC and fix problems remotely. Remote Assistance is useful for remote employees who need help with their devices or setting up new ones. Helpdesks can also use it to remotely control a user's desktop and diagnose and repair problems. To use Remote Assistance, you can: Open the Start menu Select All Apps Find Quick Assist under the letter Q Select Help Someone to create a security code Share the security code with the person you're helping via chat or on the phone The person who wants help enters the code The person who wants help will be asked if they want to share their screen Select Allow to allow the person helping to see the other person's screen You can also use Remote Help with Microsoft Intune, a cloud-based solution for secure help des...

Band Steering, Explained Band Steering for Network+: One SSID, Two Bands, One Nudge NETWORK+ FIELD NOTES · Wireless Networking Concepts · N10-009 Wireless questions on the Network+ exam love to reward precision. Two technologies can sound like they solve the same problem — too many devices, not enough bandwidth — and only one of them is the answer the question actually wants. Band steering is one of the most common technologies caught up in that confusion, mostly because its name describes exactly what it does and yet it still gets swapped for three or four look-alike wireless features. Once you can place band steering correctly against its neighbors — MU-MIMO, channel bonding, load balancing — the rest of the wireless objectives start sorting themselves the same way. The wireless optimization lineup, quickly Four technologies, one distinguishing question: what is it actually rebalancing? Technology What it rebalances Acts on Band steering Which radio band a client connec...

SFTP vs SCP  SCP (Secure Copy Protocol) and SFTP (Secure File Transfer Protocol) are both protocols that use SSH (Secure Shell) to secure data and authenticate users. However, they differ in functionality and use cases: SCP - Port 22 TCP SCP is primarily used to copy files between hosts and is faster and better suited for high-latency networks. However, it has limited functionality and can't create directories, list directories, or delete files. It is also less flexible than SFTP and will override existing files by default. SFTP - Port 22 TCP A full-featured file transfer protocol that allows users to manage files remotely. SFTP can search directories, organize files, and resume interrupted transfers. SFTP is considered a more secure successor to SCP and is becoming more common in place of SCP. Here are some more details about SCP and SFTP: Support : SFTP is supported more widely than SCP. Default behavior: Some IDEs, like JetBrains, use SFTP as the default for file tra...

 Geofencing Geofencing is a cybersecurity tool that uses GPS, Wi-Fi, RFID, or cellular data to create a virtual boundary around a physical location. It can track a device's location and trigger actions when it enters or exits the geofenced area. Geofencing (virtual boundary) can be used for a variety of purposes, including: Security Geofencing can be integrated with an organization's security infrastructure to enhance security protocols. It monitors sensitive zones, enforces compliance policies, or tracks (GPS tracking) stolen devices. Device management Geofencing (location-based services) can alert a dispatcher when a truck driver deviates from their route. When mobile devices enter company property, their cameras and microphones will be disabled. This will prevent the device from taking pictures of proprietary data or equipment and recording conversations. Audience engagement Event organizers can use geofencing to engage with the audience before or during an eve...

 Geolocation Geolocation is the process of identifying the location of a device, person, or object using technology. It can determine a device's or an individual's latitude and longitude. Geolocation can be used for many purposes, including: Mapping and navigation Geolocation data is used in mapping and navigation applications. Targeted advertising Geolocation data can target ads to users based on their location. Personalized content Geolocation data can provide personalized content to users based on their location. Payment card theft detection Financial institutions can use geolocation to detect potential payment card fraud by matching a customer's phone location with the area where their payment card is being used. Insurance claims processing Insurance claims adjusting apps can use geolocation to substantiate a policyholder's location. Asset tracking Businesses can use geolocation to manage their assets more efficiently by knowing their locat...

 GPS Tagging  GPS tagging, or geotagging, adds geographic information to digital media, such as photos, videos, or websites. This information can include latitude and longitude coordinates, place names, and other positional data. GPS tagging can be helpful for a variety of purposes, including: Sharing photos: Sharing the location where a photo was taken Keeping track of shooting spots: Keeping track of favorite shooting spots Creating location-based media : Combining geotagged media with an application like Google Maps to create location-based news and media feeds GPS tagging can also be used for other purposes, such as: Monitoring offenders Using GPS tags to monitor the location of offenders on release from prison, such as those serving time for domestic abuse or knife crime. Monitoring animals Using GPS tags to monitor the location of animals, such as cattle, to help with pasture feed intake, biosecurity, and theft detection

 Wireless Site Survey A wireless site survey is crucial in planning and designing a wireless network. It involves thoroughly evaluating a location to determine the optimal placement and configuration of wireless network components, such as access points. Here are the key aspects: Purpose Coverage: Ensure the wireless network provides adequate coverage throughout the desired area. Capacity: Assess the network’s ability to handle the expected number of devices and data traffic. Performance: Optimize the network for the best possible performance, including data rates and quality of service (QoS). Interference: Identify and mitigate sources of interference that could affect the network’s reliability. Types of Wireless Site Surveys 1. Passive Survey: Method: Collects data by listening to existing wireless traffic without connecting to the network. Use Case: Ideal for understanding the current wireless environment and identifying sources of interference. 2. Active Sur...

 Wireless Heat Map A wireless heat map is a visual tool used to represent a wireless network's signal strength and coverage within a specific area. Here are the key aspects: What It Shows Signal Strength: Heat maps use color gradients to show areas with strong and weak signals. Typically, warmer colors (red and orange) indicate stronger signals, while more excellent colors (blue and green) indicate weaker signals. Coverage: They help visualize the coverage area of wireless access points, showing where the signal is strong and where it might be weak or non-existent. Interference and Noise: Some heat maps also display areas with high interference or noise, which can affect the quality of the wireless connection. How It's Used Network Planning: Helps strategically place access points to ensure optimal coverage and performance. Troubleshooting: Identifies dead zones and areas with poor signal strength, helping to diagnose and fix connectivity issues. Optimization: Opti...

 RSSI RSSI stands for Received Signal Strength Indicator. It measures the wireless signal strength and Wi-Fi signal quality and indicates how well a device can receive a signal from a router or access point. RSSI is useful for determining whether a device has enough signal to maintain an excellent wireless connection. It's usually not visible to the receiving device's user, but IEEE 802.11 devices often make the measurement available. Factors that can affect RSSI include: Obstructions between the router and the device, such as walls or doors Signal interference from other electronic devices Distance between the router and the device Multiple devices streaming to the router An outdated router RSSI is not the same as transmitting power from a router or access point because it pulls power from the client device's Wi-Fi card.

 Cable Tester vs Cable Certifier The terms “cable certifier” and “cable tester” often get used interchangeably, but they refer to different tools with distinct purposes in network cabling. Cable Tester A cable tester is a general term that includes various tools used to check the basic functionality of network cables. These tools can be divided into two main categories: Verification Testers: Purpose: Check basic connectivity and wiring. Functions: Verify if the cable is connected correctly, check for continuity, and identify wiring issues like crossed wires. Use Case: Ideal for quick troubleshooting and ensuring that cables are correctly connected. Qualification Testers: Purpose: Determine if the cable can support specific network speeds and technologies. Functions: Test if the cable can handle data rates like 100BASE-TX, Gigabit Ethernet, or VoIP. Use Case: Useful for assessing whether existing cabling can support new network requirements. Cable Certifier ...

 Toner and Probe A toner and probe are handheld devices that trace and identify electrical systems, telecommunications, and networking cables. The two devices are: Tone generator A portable device that emits a signal or audible tone onto a specific wire or cable Probe A portable device that detects the signal or tone produced by the tone generator A toner and probe is used to: Trace the cable from the wall plate to the port on the patch panel. Trace and identify wires or cables in a bundle or group without damaging cable insulation A toner and probe effectively trace electrical cables hidden in building walls, floors, and ceilings. The tester sends an electrical pulse that bounces back when it reaches a cable. The device then picks up these pulses and displays them on its screen. Applications Telecommunications: Identifying and tracing individual wires within a cable. Networking: Tracing Ethernet cables in a LAN setup. Cable TV and Audio Systems: Identifying ...

 Syslog Logging Levels Syslog logging levels, also known as severity levels, indicate the importance or urgency of log messages. They range from 0 to 7, with 0 being the most severe and 7 being the most minor severe: 0: Emergency, the system is unusable 1: Alert, action must be taken immediately 2: Critical, critical conditions 3: Error (error): error conditions 4: Warning (warn): warning conditions 5: Notice (notice): normal but significant conditions 6: Informational (info): informational messages 7: Debug (debug): messages helpful for debugging Log levels help prioritize responses and actions. For example, alert and emergency messages are used when something wrong occurs, while critical, error, and warning messages are used for important events. Syslog is a centralized logging system that collects messages from various devices and applications. It's used for monitoring, troubleshooting, and security analysis. Regular logging is set to 0 through 4 and is for...

 Syslog Server A syslog server is a device or software that receives, stores, and manages log messages from other devices on a network. Syslog servers are also known as syslog collectors or receivers. Syslog servers are helpful for: Centralized log management: Syslog servers allow administrators to manage logs from multiple devices in one place, making it easier to search, filter, and view log messages. Identifying network issues: Syslog servers can help determine the root cause. Regulatory compliance: Syslog servers can help demonstrate compliance with regulatory frameworks that require log retention. Syslog servers typically include the following components: Syslog listener: Gathers event data and allows the collector to start receiving messages Database: Stores log messages for long-term retention and analysis Tools and interfaces: Provides tools for log analysis, filtering, and reporting Syslog servers can be physical servers, virtual machines, or software. ...

 SNMP Community String An SNMP community string is a password that allows devices to communicate with each other and access a device's statistics: Purpose: A security password that controls access to a device's statistics How it works: A user sends the community string along with a GET request to access a device's statistics Types: There are three types of community strings: read-only, read-write, and trap Use: SNMP community strings are used by devices that support SNMPv1 and SNMPv2c Default: Most devices have a default community string, often set to "public." Importance: It's essential to change the default community string to maintain device and network security SNMPv3 provides network security. All three provide device communication. During device setup, network managers typically change the default community string to a customized value. If the user has read/write/all access authority, the community string can be set using CLI or modified th...

 SNMP Simple Network Management Protocol (SNMP) is a standard protocol for managing and monitoring network devices. Here are the critical aspects of SNMP: Functionality: SNMP allows network administrators to collect information about the status and performance of network devices such as routers, switches, servers, and printers. It also enables remote configuration and control of these devices. Architecture: SNMP operates on a client-server model. The servers, called managers, collect and process information from the clients, known as agents, which are the network devices. Management Information Base (MIB): SNMP uses a hierarchical database called MIB to organize and store information about the network devices. Each device has a unique identifier within the MIB. Versions: There are three main versions: SNMPv1, SNMPv2c, and SNMPv3. Each version offers different features and security enhancements, with SNMPv3 being the only version providing security. SNMP is essential for ...

 VXLAN Virtual Extensible LAN (VXLAN) is a network virtualization technology that addresses the limitations of traditional VLANs (Virtual Local Area Networks). Here are the critical points about VXLAN: Encapsulation: VXLAN encapsulates Layer 2 Ethernet frames within Layer 4 UDP datagrams, allowing Layer 2 networks to be extended over a Layer 3 infrastructure. Scalability: Unlike traditional VLANs, which are limited to 4094 VLANs due to the 12-bit VLAN ID, VXLAN uses a 24-bit VXLAN Network Identifier (VNI). This allows for up to 16 million unique identifiers, significantly increasing scalability. Overlay Networks: VXLAN creates overlay networks on top of physical networks. This separation allows for greater flexibility and efficiency in managing network resources. VXLAN Tunnel Endpoints (VTEPs): These devices encapsulate and de-encapsulate VXLAN packets. VTEPs can be implemented in software (e.g., virtual switches) and hardware (e.g., routers and switches). VXLAN is partic...

 SDN Software-defined networking (SDN) is a network management architecture that uses software to control a network's infrastructure and traffic. SDN differs from traditional networks, which use dedicated hardware devices to control network traffic. SDN's key features include: Centralized management SDN uses a centralized platform to manage the network, making it more flexible and easier to manage. Separation of control and data planes SDN separates the control plane, implemented in software, from the data plane, implemented in network devices. Virtualization SDN can create and control virtual networks or control traditional hardware. Interoperability The SDN software can work with any router or switch, regardless of the vendor. SDN has several benefits, including: Application environments as code: SDN can deliver application environments as code, which can reduce network management time. Real-time adaptation: SDN is well suited to emerging technologies l...

 WHOIS WHOIS is a public database that contains information about domain names, IP addresses, and other internet resources: What it contains WHOIS records include the name and contact information of the domain owner, the registrar, the registration and expiration dates, and more What it's used for WHOIS is used to verify domain names, resolve technical issues, and investigate cybercrime How it works WHOIS is a query and response protocol that stores and delivers information in a human-readable format Who regulates it The International Corporation for Assigned Names and Numbers (ICANN) regulates the WHOIS database. Who maintains it Different domain registrars and registries manage the WHOIS database for specific TLDs, such as .com and .net WHOIS is a vital tool for maintaining the integrity of the domain name registration process. However, there are some limitations to WHOIS lookup: Some TLDs, like country-code level domains (.us, .ca, .uk, and .eu), don'...

 DMARC Domain-based Message Authentication, Reporting, and Conformance (DMARC) is an email security protocol that helps protect users from forged emails and email spoofing: How it works DMARC builds on the Domain Name System (DNS), DomainKeys Identified Mail (DKIM), and Sender Policy Framework (SPF) protocols to verify email senders. DMARC policies tell receiving email servers what to do with messages that don't pass these authentication checks. What it does DMARC helps prevent email spoofing, which occurs when attackers use an organization's domain to impersonate its employees. DMARC can also help protect a brand's reputation by blocking spoofed messages. How to set it up Administrators set up DMARC after SPF and DKIM. DMARC records are published as text (TXT) resource records (RR) in the sending organization's DNS database. How to use it DMARC policies can specify what to do with messages that fail authentication, such as moving them to the recipient...