CompTIA Network+ (N10-009) flashcards

Different classifications of fiber optic cables distinguished by core diameter, light source, bandwidth, and maximum distance capabilities for various Ethernet speeds.

• Multimode (OM) uses LEDs or VCSELs, multiple light paths, shorter distances.
• Single-mode (OS) uses lasers, single light path, longer distances.
• OM3/OM4 are 'laser-optimized' multimode for higher speeds (10GbE+) over longer multimode distances.

Memory trick: Think of fiber types like car lanes: Multimode has many lanes (light paths) but gets congested faster. Single-mode has one super-fast lane for long hauls.

A logical grouping of network devices that allows them to communicate as if they were on the same physical segment, regardless of their actual physical location, creating separate broadcast domains.

• Divides a single physical switch into multiple logical switches.
• Reduces broadcast traffic and improves security.
• Requires a Layer 3 device (router or Layer 3 switch) to route traffic between different VLANs.

Memory trick: Think of VLANs as virtual rooms in a house, each with its own conversations.

A highly directional antenna used for long-distance, point-to-point or point-to-multipoint wireless communication, characterized by a series of parallel elements (director, driven element, reflector) on a boom.

• Provides high gain and a narrow beamwidth.
• Effective for overcoming distance and interference in focused directions.
• Requires careful alignment for optimal performance.

Memory trick: Think of a Yagi as a spotlight for your Wi-Fi signal, aiming it exactly where you need it.

Interference that occurs when multiple wireless devices or access points transmit on the same frequency channel within the same geographical area, leading to performance degradation due to increased collisions and retransmissions.

• Common in dense Wi-Fi deployments without proper channel planning.
• Causes include overlapping AP coverage using identical channels.
• Mitigated by careful channel planning, power adjustments, and proper AP placement.

Memory trick: Think of radio channels like lanes on a highway; too many cars in one lane causes traffic jams.

A disaster recovery site that is a fully operational, continuously updated replica of the primary data center, designed to allow for immediate or near-immediate failover with minimal data loss and downtime.

• Lowest RTO (Recovery Time Objective).
• Lowest RPO (Recovery Point Objective).
• Most expensive to maintain due to full redundancy and synchronization.

Memory trick: DR sites go from Hot's speed to Cold's savings.

A condition where a network interface or port repeatedly changes state from up to down and back up again.

• Often indicates a physical layer problem (cable, connector, NIC, port).
• Can be caused by loose connections, faulty hardware, or power issues.
• Causes network instability and intermittent connectivity.

Memory trick: Link keeps leaping, likely loose.

A cabling fault where two wires from different twisted pairs are swapped at both ends of a cable, compromising the pair's twisting and increasing crosstalk.

• Occurs when a wire from one pair is crimped into the position of a wire from another pair.
• Does not always result in a complete circuit break, but degrades signal quality.
• Leads to increased crosstalk, higher error rates, and reduced network performance.

Memory trick: Cables can be broken, crossed, or shorted; each has its own pain.

A network of compromised computers (bots) controlled by a single attacker (bot-herder) via a command-and-control (C2) server, used for malicious activities.

• Infected machines (bots) communicate with a C2 server for instructions.
• Often uses encrypted and irregular communication patterns to avoid detection.
• Can be used for DDoS attacks, spamming, data theft, and more.

Memory trick: Malware talks in different ways; C2 is the bot's secret language.

A method for IPv6 address assignment where devices automatically configure their IP addresses using router advertisements (SLAAC) and then obtain additional network configuration information, such as DNS server addresses, from a DHCPv6 server in stateless mode.

• SLAAC handles address generation from router advertisements.
• Stateless DHCPv6 provides supplementary information like DNS.
• No central server manages IP address leases for stateless DHCPv6.

Memory trick: IPv6's address options: Auto-assign, Serve-all, or Hand-set.

A standard protocol used for sending system log or event messages from a network device to a centralized logging server. It allows for the collection and analysis of logs from various sources.

• Standard for collecting diverse log messages.
• Uses UDP port 514 by default.
• Messages include facility and severity levels for categorization.

Memory trick: Logging needs a 'Sys'tematic 'Log' collector.

Occurs when IP packets from a source to a destination take a different path than return packets from the destination to the source.

• Can cause issues with stateful firewalls, load balancers, and network monitoring tools.
• Often results in dropped packets or connection timeouts.
• Troubleshooted using traceroute from both ends and examining routing tables.

Memory trick: Routes Diverge, Stateful Firewalls Frown.

A logical Layer 3 interface on a Layer 3 switch that is associated with a VLAN. It allows the switch to perform Layer 3 routing functions for traffic originating from or destined to that VLAN.

• Acts as the default gateway for devices within its associated VLAN.
• Requires an IP address and subnet mask.
• Enables inter-VLAN routing without needing an external router for internal VLAN traffic.

Memory trick: Think of an SVI as a 'virtual router port' for each VLAN, allowing them to talk.

The orientation of the electric field of an electromagnetic wave, usually defined as vertical, horizontal, or circular.

• For optimal signal reception, transmitting and receiving antennas should have matching polarization.
• Mismatch can lead to significant signal loss (up to 20-30 dB).
• Important for point-to-point and point-to-multipoint wireless links.

Memory trick: Antennas must align to shine.

A software tool used to identify security weaknesses in systems, applications, and networks by comparing configurations and software versions against a database of known vulnerabilities.

• Automates the process of identifying security flaws.
• Checks for misconfigurations, missing patches, and weak security settings.
• Provides reports on identified vulnerabilities and often suggests remediation steps.

Memory trick: Tools for security: Scan for weaknesses, Analyze traffic, Guard ports.

An IEEE standard for port-based Network Access Control (NAC) that provides an authentication mechanism to devices wishing to attach to a LAN or WLAN.

• Requires devices to authenticate before gaining network access.
• Uses an authenticator (switch/AP), supplicant (client), and authentication server (RADIUS).
• Can enforce policies based on user, device, or group.

Memory trick: Access control: Who gets in, and what they can do.

The third layer of the OSI model, responsible for logical addressing, routing packets between different networks, and determining the best path for data.

• Uses IP addresses for logical addressing.
• Routers operate at this layer.
• Responsible for fragmentation and reassembly of packets.

Memory trick: Please Do Not Touch Steve's Pet Alligator. (Physical, Data Link, Network, Transport, Session, Presentation, Application)