A switch is a network device that connects multiple devices on a local area network (LAN) and forwards data packets between them. A switch can be identified by its icon, which is a rectangle with four curved lines on each side. In the attached network diagram, device D is the switch, as it matches the icon and connects three computers to device A, which is another network device. Reference:
[What is a Network Switch and How Does it Work?]
[Network Diagram Symbols and Icons | Lucidchart]

SOAR tools ingest aggregated alerts from detection sources (such as SIEMs, network security tools, and mailboxes) before executing automatable, process-driven playbooks to enrich and respond to these alerts.
https://www.paloaltonetworks.com/cortex/security-operations-automation

An AAAA record is a type of DNS record that maps a domain name or a subdomain to an IPv6 address. IPv6 is the latest version of the Internet Protocol (IP) that uses 128-bit addresses to identify devices on the internet. An AAAA record is similar to an A record, which maps a domain name or a subdomain to an IPv4 address, but with a different format and length. An example of an AAAA record is:
example-website.com. IN AAAA 2001:db8::1234
In the example above, the record is made up of the following elements:
example-website.com.: The domain name or the subdomain that is mapped to an IPv6 address.
IN: The class of the record, which indicates that it is on the internet.
AAAA: The type of the record, which indicates that it is an IPv6 address record.
2001:db8::1234: The IPv6 address that is mapped to the domain name or the subdomain. The address is written in hexadecimal notation, with colons separating each 16-bit segment. Double colons (::) can be used to compress consecutive zero segments.
:
Palo Alto Networks Certified Cybersecurity Entry-level Technician (PCCET) - Palo Alto Networks DNS AAAA record | Cloudflare What's an AAAA record? - DNSimple Help List of DNS record types - Wikipedia

A rootkit is a type of malware that enables cyber criminals to gain access to and infiltrate data from machines without being detected. It covers software toolboxes designed to infect computers, give the attacker remote control, and remain hidden for a long period of time1 One of the most prominent characteristics of a rootkit is that it cannot be detected by antivirus because of its masking techniques. A rootkit may be able to subvert the software that is intended to find it, such as by hooking system calls, modifying kernel objects, or tampering with the registry2 Another prominent characteristic of a rootkit is that it takes control of the operating system. A rootkit may install itself in the kernel or the firmware of the device, giving it the highest level of privilege and access. A rootkit may also replace the bootloader or the BIOS of the machine, making it difficult to remove. A rootkit can use its control over the operating system to launch other malware, such as ransomware, bots, keyloggers, or trojans34 Reference:
1: What Is a Rootkit? How to Defend and Stop Them? | Fortinet
2: Rootkit - Wikipedia
3: What Is a Rootkit? - Microsoft 365
4: What is Rootkit? Attack Definition & Examples - CrowdStrike

A host-based architecture uses virtual machines (VMs) to run workloads on a shared host, commonly found in public cloud environments. Each VM operates independently with its own OS, making this model suitable for traditional and isolated application deployments.