Certified - CompTIA Network +

Welcome to this glossary edition of the A Plus PrepCast. In this episode, we will explore essential acronyms beginning with the letters A through D that are commonly tested on the Network Plus certification exam. By mastering the meaning and context of each term, you will strengthen your ability to recognize and apply these concepts throughout your studies and the exam itself.
A A A stands for Authentication, Authorization, and Accounting. These three processes work together to manage secure access to systems and track user activity. Authentication verifies a user's identity, Authorization defines what resources that user can access, and Accounting logs what actions the user performs. This trio is essential to network security and is often implemented in remote access and enterprise systems.
A C L refers to an Access Control List, which is used to control the flow of network traffic. A C Ls apply rules based on criteria such as I P address, port number, or protocol type. These rules can allow or deny traffic and are often configured on routers and firewalls. A C Ls are key to enforcing access policies and isolating traffic between different segments of a network.
A E S means Advanced Encryption Standard, a symmetric encryption method widely used for securing data. It uses fixed-length keys of one twenty-eight, one ninety-two, or two fifty-six bits to encrypt information in blocks. A E S is used in many technologies including W P A two wireless security and virtual private networks. Its strength and speed make it a global standard for data confidentiality.
A H stands for Authentication Header, a protocol within the I P Security suite. It provides integrity and origin authentication for I P packets but does not encrypt the content itself. A H ensures that data has not been altered in transit and confirms the sender’s identity. It is useful when data needs to be trusted but not hidden.
A P refers to an Access Point, a device that connects wireless clients to a wired network. It acts as a bridge between wireless communication and the local area network infrastructure. Access Points can be standalone or part of a managed wireless system. They are central to enabling Wi-Fi in homes, offices, and public networks.
A P C stands for Angled Physical Contact, a type of fiber optic connector design. Its angled end face reduces signal reflection, which helps improve signal quality. A P C connectors are typically green and used in high-performance optical links. They offer better return loss than flat or ultra-polished connectors.
A P I P A means Automatic Private I P Addressing, a fallback method used when a device cannot contact a D H C P server. It assigns an I P address in the one sixty-nine dot two fifty-four dot x dot x range to maintain local network communication. A P I P A is not routable beyond the local link. It is often a sign of connectivity issues during troubleshooting.
A R P refers to Address Resolution Protocol, which maps I P addresses to M A C addresses on a local network. This mapping is necessary for devices to communicate within the same subnet. A R P broadcasts requests and stores the results in a temporary cache. It is essential for Layer Two functionality and can be a target for spoofing attacks.
A U P stands for Acceptable Use Policy, a document that outlines the rules for using an organization’s IT resources. It defines appropriate behaviors and prohibited activities for users. A U Ps help protect company assets and enforce compliance standards. Users are often required to agree to them before gaining access to the network.
B G P is the Border Gateway Protocol, which routes traffic between large networks known as autonomous systems. It evaluates path attributes to determine the best route for data across the internet. B G P is essential for core internet routing and supports redundancy and failover. Misconfiguration of B G P can lead to major connectivity issues globally.
B N C stands for British Naval Connector, also known as Bayonet Neill Concelman. It is a type of coaxial connector that uses a twist-and-lock mechanism for secure cable connections. B N C connectors were commonly used in early Ethernet networks and are still found in video transmission and legacy setups. Although largely replaced by modern cabling methods, understanding B N C helps when working with older network hardware.
B Y O D refers to Bring Your Own Device, a policy that allows employees to use personal laptops, smartphones, or tablets for work purposes. While this increases flexibility and user convenience, it introduces additional security and compliance risks. Organizations that support B Y O D often enforce policies for data protection, device encryption, and remote wiping. On the exam, B Y O D may appear in scenarios involving access control and endpoint management.
C A M means Content Addressable Memory, a type of memory used in network switches to store M A C address tables. When a frame arrives, the switch uses the C A M table to decide which port to forward the frame to, based on the destination M A C address. This process enables efficient Layer Two switching. Understanding how switches use C A M is essential for grasping how traffic is handled within a local network.
C A N stands for Campus Area Network, which connects multiple buildings in a limited geographic area such as a school, hospital, or business campus. It is larger than a local area network but smaller than a metropolitan or wide area network. C A Ns typically use high-speed fiber connections between buildings and integrate both wired and wireless segments. These networks often support shared services like file servers, printers, and databases across departments.
C D M A refers to Code Division Multiple Access, a wireless communication technique where multiple users share the same frequency band. Each signal is encoded with a unique identifier, allowing simultaneous transmission without interference. C D M A was widely used in early cellular networks and still appears in legacy mobile systems. While newer technologies have replaced it, the concept remains important for understanding how spectrum is shared.
C I A stands for Confidentiality, Integrity, and Availability, the three core principles of cybersecurity. Confidentiality ensures that sensitive data is only accessible to authorized users. Integrity protects data from being altered without detection, and Availability ensures that systems remain accessible when needed. The C I A triad forms the foundation for designing, implementing, and evaluating security policies and technologies.
C I D R means Classless Inter-Domain Routing, a method used to allocate and route I P addresses more efficiently. Unlike the older class-based system, C I D R allows flexible subnetting using variable-length subnet masks. This reduces I P address waste and supports more precise route summarization. On the exam, C I D R appears in questions about subnetting and address planning.
C L I refers to Command Line Interface, a method of interacting with an operating system or network device by typing text commands. Unlike graphical interfaces, C L I offers direct control and access to advanced configuration options. It is commonly used in routers, switches, and firewalls. Familiarity with C L I syntax is important for performing tasks like interface configuration and troubleshooting.
C N A M E stands for Canonical Name, a type of record in the Domain Name System that maps one domain name to another. It is used to create an alias, allowing multiple domain names to resolve to the same I P address or target. C N A M E records simplify domain management and are often used in load balancing and branding. They must be used carefully, as improper configuration can lead to resolution failures.
C P U is the Central Processing Unit, which performs the basic instructions and calculations that run a computing device. It serves as the brain of the system, executing code and managing data flow. In networking devices like routers and firewalls, the C P U handles both control plane and data plane functions. Understanding how C P U performance affects throughput and latency is useful for analyzing bottlenecks.
C R C refers to Cyclic Redundancy Check, an error-checking technique used to detect data corruption during transmission. It works by generating a hash value based on the data, which is then compared on the receiving end. If the values do not match, the data is considered invalid and may be retransmitted. C R C is commonly found in Ethernet frames, storage systems, and other communication protocols.
C S M A slash C A stands for Carrier Sense Multiple Access with Collision Avoidance, a protocol used in wireless networks. Devices first check if the medium is free before transmitting and use techniques like acknowledgments and waiting periods to prevent collisions. This differs from wired collision detection protocols due to the difficulty of sensing in wireless environments. C S M A slash C A is integral to Wi-Fi standards such as I E E E eight oh two dot eleven.
C S M A slash C D refers to Carrier Sense Multiple Access with Collision Detection, which was commonly used in early wired Ethernet networks. Devices listen to the medium before sending data and can detect if a collision occurs during transmission. If a collision is detected, each device waits a random time before retrying. Though largely obsolete today due to the use of switches, it remains a relevant historical concept.
C S U means Channel Service Unit, a device that connects digital circuits from the service provider to the customer's internal equipment. It ensures proper signal formatting and timing for communication over leased lines. A C S U is often paired with a D S U to form a complete interface. Together, these devices enable access to T one lines and other carrier services.
C V E stands for Common Vulnerabilities and Exposures, a standardized system for identifying publicly known cybersecurity flaws. Each C V E entry includes a unique identifier, a brief description, and reference links. This allows security professionals to track vulnerabilities across different platforms and tools. On the exam, C V E may appear in contexts involving patching, vulnerability management, or threat intelligence.
C W D M refers to Coarse Wavelength Division Multiplexing, a method for transmitting multiple optical signals over a single fiber by assigning them to different light wavelengths. C W D M supports fewer channels than its dense counterpart but is more cost-effective for shorter distances. It is used in environments that require moderate bandwidth without the expense of D W D M. Understanding C W D M helps in evaluating fiber optic transport options.
D A A S means Desktop as a Service, a cloud computing model where virtual desktops are hosted and managed by a service provider. Users can access their desktop environments from anywhere using thin clients or standard web browsers. D A A S reduces the need for physical desktop infrastructure and simplifies patching and deployment. It is relevant in enterprise, education, and remote work scenarios.
D B stands for Decibel, a logarithmic unit used to express ratios of power, voltage, or signal strength. In networking, D B measurements are common in assessing signal loss over cables and wireless links. A negative D B value typically indicates loss, while positive values may indicate amplification. Knowing how to interpret D B levels is essential when working with physical media and radio frequencies.
D D o S refers to Distributed Denial of Service, an attack where multiple systems flood a target with traffic to exhaust resources. Unlike standard denial of service attacks, D D o S uses a large network of compromised machines. The result is service disruption or complete unavailability. These attacks are a major concern for uptime and are mitigated using firewalls, rate limiting, and specialized filtering tools.
D H C P is Dynamic Host Configuration Protocol, which automatically assigns I P addresses and other network settings to client devices. This eliminates the need for manual configuration and reduces the chance of address conflicts. D H C P servers issue time-based leases, and clients periodically renew them. On the exam, D H C P is often tested in troubleshooting and network initialization scenarios.
D L P stands for Data Loss Prevention, a set of strategies and technologies used to ensure that sensitive data does not leave an organization in an unauthorized way. It can involve monitoring data in motion across the network, data at rest on storage systems, or data in use on endpoints. D L P solutions can block or alert on policy violations, such as sending confidential information via email or copying it to removable drives. On the Network Plus exam, understanding D L P is important for identifying how organizations protect intellectual property, customer records, or internal communications.
D N S means Domain Name System, the hierarchical system responsible for translating human-friendly domain names into numerical I P addresses. Without D N S, users would have to memorize numeric addresses for every website or network resource they wish to access. When a user types a web address, the D N S resolver queries servers to return the correct address associated with that name. D N S is central to internet functionality and is covered on the exam in questions involving resolution failure, record types, and misconfigured zones.
D o S refers to Denial of Service, a type of cyber attack that seeks to disrupt normal operations by overwhelming a system with excessive traffic or resource requests. A single source typically generates these attacks, using up bandwidth, CPU cycles, or memory until the target becomes unresponsive. While less sophisticated than distributed versions, D o S attacks can still cause significant service outages. The exam may reference D o S in questions related to risk mitigation, firewall configuration, or intrusion detection.
D S L stands for Digital Subscriber Line, a technology that delivers high-speed internet access using standard telephone lines. It allows for simultaneous voice and data transmission by using higher frequencies for internet signals. There are various forms of D S L, including A D S L and V D S L, each with different speed capabilities and distance limitations. Understanding D S L helps in identifying broadband technologies and their physical media characteristics.
D S U means Data Service Unit, which is often used in conjunction with a Channel Service Unit to connect digital communication lines, such as T one circuits, to local networks. The D S U converts digital signals from the telecom provider into a format the internal network equipment can understand. This function ensures signal timing and proper framing for reliable communication. On the exam, D S U may appear in contexts involving WAN connections and legacy network infrastructure.
D W D M is Dense Wavelength Division Multiplexing, a fiber optic technology that enables multiple data streams to be transmitted over a single fiber using closely spaced light wavelengths. This approach dramatically increases bandwidth capacity and supports long-distance communication without needing additional fibers. D W D M is used in service provider backbones and large enterprise networks. Understanding D W D M helps differentiate it from C W D M and other fiber technologies on the exam.
E A P refers to Extensible Authentication Protocol, a flexible authentication framework commonly used in wireless networks and point-to-point connections. E A P supports a variety of authentication methods, including passwords, certificates, and smart cards. It is frequently used in W P A two Enterprise networks, where strong identity validation is necessary before granting access. On the Network Plus exam, E A P may be mentioned in questions related to wireless security standards and RADIUS configurations.
E I A stands for Electronic Industries Alliance, an organization responsible for setting hardware standards used in electrical and electronic equipment. Although the group was dissolved in two thousand ten, its legacy continues in standards like E I A slash T I A six oh eight and R S two thirty-two, which are still referenced in cabling and serial communications. Many connectors and transmission standards used in networking equipment were originally developed under the E I A’s guidance. On the exam, E I A references may appear in cabling, transmission, and physical layer contexts.
E I G R P means Enhanced Interior Gateway Routing Protocol, a Cisco-proprietary dynamic routing protocol used within autonomous systems. It uses a combination of metrics such as bandwidth, delay, and reliability to determine the best path for data. E I G R P offers faster convergence and less overhead compared to older protocols like R I P. While it is not an open standard, understanding E I G R P is useful for interpreting protocol characteristics and comparing it to alternatives like O S P F on the certification exam.