ITCA flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

OSI Layer 3

The Network layer, responsible for logical addressing (IP addresses) and routing packets between different networks. Routers operate primarily at this layer using routing tables to forward traffic.

TCP vs UDP

TCP is connection-oriented with handshakes, sequencing, and retransmission for reliability. UDP is connectionless with no guarantees, used for streaming, DNS queries, and VoIP where speed matters more than delivery certainty.

DHCP function

Dynamic Host Configuration Protocol automatically assigns IP addresses, subnet masks, default gateways, and DNS servers to clients. It uses the DORA process: Discover, Offer, Request, Acknowledge.

DNS purpose

Domain Name System translates human-readable hostnames such as www.example.com into IP addresses. It typically uses port 53 and relies on hierarchical root, TLD, and authoritative servers.

APIPA address

An automatic private IP address in the 169.254.0.0/16 range that a Windows host self-assigns when no DHCP server is reachable. Its presence usually signals a DHCP or connectivity failure.

Subnet mask /24

A 24-bit mask written 255.255.255.0, leaving 8 host bits. It yields 256 total addresses and 254 usable host addresses after reserving the network and broadcast addresses.

Default gateway

The IP address of the router interface that a host sends traffic to when the destination is outside its local subnet. Without a correct gateway, only local network communication succeeds.

MAC address

A 48-bit hardware address burned into a network interface card, written as six hexadecimal pairs. Switches use MAC addresses at Layer 2 to forward frames within a local network segment.

SSD vs HDD

Solid-state drives use flash memory with no moving parts, offering faster access, lower power draw, and better shock resistance. Hard disk drives use spinning platters and are cheaper per gigabyte for bulk storage.

RAM characteristics

Random access memory is volatile working storage that loses its contents when power is removed. More RAM allows more applications and data to be held in fast memory simultaneously.

BIOS and UEFI

Firmware that initializes hardware at boot and locates the operating system. UEFI is the modern replacement for legacy BIOS, supporting larger drives, faster startup, and Secure Boot.

Motherboard components

The main circuit board hosting the CPU socket, RAM slots, expansion slots, chipset, and connectors for storage and peripherals. It provides the pathways that let all components communicate.

Peripheral connection types

USB is a general-purpose hot-swappable bus for most peripherals. HDMI and DisplayPort carry video and audio, while Thunderbolt combines high-speed data, video, and power over one connector.

Power supply unit

Converts AC wall power to regulated DC voltages the computer components require. Its wattage rating must exceed total system draw, and higher efficiency ratings reduce wasted heat.

Virtualization basics

A hypervisor runs multiple isolated virtual machines on one physical host. Type 1 runs directly on hardware, Type 2 runs on a host operating system, and each VM has its own virtual hardware.

Cloud service models

IaaS delivers virtualized infrastructure, PaaS delivers a managed development platform, and SaaS delivers complete applications over the internet. Responsibility for management shifts from customer to provider across these models.

Operating system role

The OS manages hardware resources, schedules processes, manages memory and file systems, and provides a user interface. Examples include Windows, macOS, and Linux distributions.

File system types

NTFS is the Windows default with permissions and journaling; FAT32 has a 4 GB file limit; exFAT suits large removable media; ext4 is common on Linux; APFS is used by macOS.

Patch management

The process of identifying, testing, and deploying software updates that fix bugs and close security vulnerabilities. Regular patching reduces exposure to known exploits.

CIA triad

Confidentiality protects data from unauthorized disclosure, integrity ensures data is unaltered and trustworthy, and availability ensures systems and data are accessible when needed.

Authentication vs authorization

Authentication proves who a user is through credentials such as passwords or tokens. Authorization determines what that authenticated user is permitted to access or perform.

Phishing characteristics

Deceptive messages impersonating trusted entities to trick recipients into revealing credentials or clicking malicious links. Warning signs include urgency, mismatched sender addresses, and unexpected attachments.

Malware categories

Viruses attach to files, worms spread across networks without user action, trojans disguise as legitimate software, and ransomware encrypts data for extortion. Each requires different countermeasures.

Firewall function

Filters network traffic based on rules that permit or deny packets by address, port, and protocol. It can be host-based software or a dedicated network appliance at the perimeter.

Encryption at rest

Protects stored data by converting it to unreadable ciphertext unless the correct key is supplied. Full-disk encryption and database encryption are common implementations.

Multi-factor authentication

Requires two or more independent verification factors from categories such as something you know, something you have, and something you are. It reduces risk from stolen passwords.

Backup 3-2-1 rule

Keep at least three copies of data, on two different media types, with one copy stored offsite. This protects against hardware failure, site disasters, and ransomware alike.

Incremental vs differential backup

Incremental backups capture changes since the last backup of any kind and are fast to create but slow to restore. Differential backups capture changes since the last full backup.

Troubleshooting methodology

Identify the problem, establish a theory, test it, form a plan of action, implement the fix, verify full functionality, and document findings. Following the sequence prevents skipped verification steps.

Help desk ticketing

A system that records incidents with priority, category, and status so requests are tracked, escalated, and resolved consistently. It also supplies metrics such as resolution time.

Change management

A controlled process for requesting, reviewing, approving, and documenting changes to IT systems. It reduces outages by ensuring rollback plans and stakeholder awareness exist before implementation.

Remote access tools

Technologies such as VPNs and remote desktop protocols that let users reach internal resources securely from outside. VPNs encrypt tunnels, while RDP typically uses port 3389.