Term 211
Direct-attached Storage
Direct-attached Storage (DAS) is a storage device connected directly to a computer or server without going through a network.
Acronym study
Terms 211–240 of 1033 N10-009 acronyms and key terms. Each entry includes a plain-English definition and a link to the full 800-word glossary page with exam context and practice questions.
Term 211
Direct-attached Storage (DAS) is a storage device connected directly to a computer or server without going through a network.
Term 212
Disaster recovery is a set of policies, procedures, and tools that help an organization restore critical IT systems and data after a disruptive event.
Term 213
A DLL error is a message that appears when a Windows program cannot find or properly use a Dynamic Link Library file it needs to run.
Term 214
dmesg is a Linux command that displays messages from the kernel ring buffer, used to diagnose hardware and boot issues.
Term 215
A DMZ (demilitarized zone) is a network segment that sits between an internal private network and the public internet, hosting publicly accessible services while keeping the internal network isolated.
Term 216
DNS is the system that translates human-friendly domain names like example.com into machine-readable IP addresses so computers can find each other on a network.
Term 217
DNS poisoning is a cyberattack that corrupts a DNS resolver's cache with false information, redirecting users to malicious websites without their knowledge.
Term 218
A DNS zone is a distinct part of the global Domain Name System (DNS) namespace that is delegated to a specific administrator or organization for management, containing resource records for a domain.
Term 219
DNSSEC adds cryptographic signatures to DNS records to ensure data authenticity and integrity, preventing cache poisoning and spoofing attacks.
Term 220
A docking station is a hardware device that lets you connect a laptop to multiple peripherals like monitors, keyboards, and mice through a single connection point.
Term 221
DoH encrypts DNS queries within HTTPS traffic to prevent eavesdropping and manipulation of domain name resolution.
Term 222
The Domain Name System (DNS) is the internet's phonebook that translates human-friendly domain names like google.com into computer-friendly IP addresses like 172.217.0.46.
Term 223
A cyberattack that floods a target with traffic or requests to exhaust its resources, making it unavailable to legitimate users.
Term 224
DNS over TLS (DoT) encrypts DNS queries using TLS, ensuring privacy and integrity between clients and resolvers.
Term 225
Dot1Q is the industry-standard networking protocol that tags Ethernet frames with a VLAN identifier, allowing multiple virtual LANs to share the same physical network link.
Term 226
Double Data Rate (DDR) is a technology that doubles the data transfer rate of a memory or bus by sending data on both the rising and falling edges of the clock signal, effectively doing twice as much work per clock cycle.
Term 227
Drive wiping is the process of completely and permanently erasing all data on a storage drive so that it cannot be recovered.
Term 228
Driver rollback is a Windows tool that reverts a device driver to its previous version to fix problems caused by a recent driver update.
Term 229
An OSPF router that lost the DR/BDR election on a multi-access segment.
Term 230
DSCP (Differentiated Services Code Point) is a 6-bit field in an IP packet header used to classify and prioritize network traffic for Quality of Service (QoS).
Term 231
DSL (Digital Subscriber Line) is a technology that uses existing telephone lines to provide high-speed internet access without interrupting your phone service.
Term 232
Dynamic Trunking Protocol (DTP) is a Cisco proprietary protocol used to automatically negotiate whether a switch port should operate in access mode or trunk mode.
Term 233
A Dual In-line Memory Module (DIMM) is a small circuit board that holds memory chips and plugs into a computer's motherboard to provide Random Access Memory (RAM).
Term 234
A duplex mismatch occurs when two connected network devices are configured with different duplex settings (one half-duplex, one full-duplex), leading to poor performance and data errors.
Term 235
Dynamic ARP Inspection is a security feature that validates ARP packets on a network to prevent man-in-the-middle attacks by ensuring that only legitimate ARP messages are forwarded.
Term 236
Dynamic auto is a switchport trunking mode where the port will automatically form a trunk if it receives a trunk negotiation request from the other device, but will not actively initiate trunking.
Term 237
A Cisco proprietary switchport mode that makes a port actively request to form a trunk but also allow the port to become a trunk if the connected device requests it.
Term 238
DHCP is a network protocol that automatically assigns IP addresses and other configuration settings to devices so they can communicate on a network.
Term 239
Dynamic NAT is a method of mapping multiple private IP addresses to a pool of public IP addresses automatically, allowing many devices to share a limited number of public addresses.
Term 240
A route that is automatically learned and updated by a router using a routing protocol, rather than being manually configured.