Certification terms: V
171 study terms starting with V.
171 terms
- /var DirectoryThe Linux directory for variable data that changes during operation, including logs, spool files, caches and databases.Foundational
- VACUUM CommandA Delta Lake command that permanently deletes data files no longer referenced by the table and older than the retention threshold (7 days by default).Advanced
- Validate ScopeProcess of formalizing acceptance of completed project deliverables.Foundational
- Validation DatasetHeld-out data used during development to tune hyperparameters and select models.Foundational
- Validation RuleRule containing a formula that returns true when data is invalid, blocking the save and showing an error message.Foundational
- Value DeliveryGovernance outcome ensuring IT and security investments deliver the expected business benefits at optimal cost.Intermediate
- Value Delivery SystemStrategic business activities that build, sustain, and advance an organization through portfolios, programs, projects, and operations.Intermediate
- Value Engineering (VE)Systematic approach to finding less costly ways to complete the same work while preserving function.Intermediate
- Value StreamEnd-to-end collection of value-adding activities that creates an overall result for a customer, stakeholder or end user.Foundational
- Value Stream MapDiagram of value stream stages with entrance and exit criteria, participating stakeholders and value items.Intermediate
- Value Stream Mapping (VSM)A Lean technique that visualizes every step, wait time, and handoff required to deliver a change from request to customer.Intermediate
- Vanishing GradientA training problem where gradients shrink toward zero in early layers, so they learn very slowly or not at all.Intermediate
- Vanity MetricsMetrics that look impressive but do not inform decisions or reflect real value.Intermediate
- VariableQuestion or field on a catalog item or record producer that captures user input.Foundational
- Variable Length Subnet Mask (VLSM)Using different subnet mask lengths within the same address space to match each subnet's size to its host requirement.Intermediate
- Variable SamplingStatistical sampling method used in substantive testing to estimate a monetary or numeric value.Intermediate
- Variable SetReusable group of variables shared across multiple catalog items.Intermediate
- VarianceThe average squared deviation from the mean, measuring how spread out data are; units are the square of the data's units.Intermediate
- Variance AnalysisTechnique for determining the cause and degree of difference between baseline and actual performance.Foundational
- Variance at Completion (VAC)Projected budget deficit or surplus at project end: VAC = BAC - EAC.Intermediate
- VARIANT Data TypeA Snowflake data type that stores semi-structured data such as JSON, Avro, ORC, Parquet or XML, with a maximum size of 128 MB per value.Intermediate
- Variational Autoencoder (VAE)A generative autoencoder that learns a probabilistic latent space from which new samples can be drawn.Advanced
- vCoreMuleSoft unit of compute capacity used to size and license application replicas or workers.Intermediate
- vCore Purchasing ModelAn Azure SQL pricing model in which you choose virtual cores, memory and storage independently, with General Purpose, Business Critical and Hyperscale tiers.Intermediate
- Vector DatabaseA database optimized for storing embeddings and performing fast similarity search over them.Foundational
- Vector IndexA data structure that organizes embeddings for efficient similarity search.Intermediate
- VelociraptorAn open-source endpoint visibility and digital forensics tool that queries many endpoints at scale using VQL.Advanced
- VelocityThe amount of work, usually in story points, a team completes per iteration.Foundational
- Vendor DiversityUsing products from different vendors in layered defenses so a single flaw cannot defeat all layers.Intermediate
- Vendor Due DiligencePre-contract evaluation of a vendor's security, privacy, financial, operational, and compliance posture.Intermediate
- Vendor Lock-InDependence on a provider's proprietary services or formats that makes switching providers costly or difficult.Foundational
- Vendor Risk AssessmentQuestionnaire-based evaluation of a third party's controls, sent through the vendor portal.Intermediate
- Verbose Error MessageAn error message that reveals internal details such as stack traces, queries, file paths or software versions.Foundational
- Verifiable Credential (VC)Cryptographically signed digital credential, defined by the W3C, that a holder can present and a verifier can check independently.Advanced
- Verification and Validation (V&V)Verification checks that software is built correctly against its specifications; validation checks that the right software was built for user needs.Intermediate
- Verified DeliverablesCompleted project deliverables checked and confirmed for correctness through Control Quality.Foundational
- Verify Full System FunctionalityStep five of troubleshooting: confirm the fix works end to end and apply preventive measures.Foundational
- Vertex AIGoogle Cloud's unified AI platform for building, deploying and scaling ML models and generative AI applications and agents.Foundational
- Vertical Alignment (VA)An LCD panel type with high contrast ratios and deep blacks but slower response than IPS or TN.Intermediate
- Vertical PartitioningSplitting a table by columns into separate tables that share the primary key.Intermediate
- Vertical Pod Autoscaler (VPA)A Kubernetes add-on that recommends or automatically adjusts container CPU and memory requests based on usage.Advanced
- Vertical ScalingIncreasing or decreasing capacity by changing the size of an existing resource, such as more CPU or RAM; also called scaling up/down.Foundational
- Vertical SliceA piece of functionality that cuts through all architectural layers to deliver end-to-end value.Intermediate
- VertiPaqThe in-memory columnar storage engine behind Power BI Import mode, Analysis Services Tabular and Power Pivot.Advanced
- Very High Throughput (VHT)The 802.11ac PHY and MAC enhancements.Intermediate
- Very Low Power (VLP)A 6 GHz device class for short-range portable use indoors and outdoors without AFC.Advanced
- Video Bandwidth ProvisioningSizing network capacity for video by adding overhead, typically about 20 percent, to the configured video call rate.Advanced
- Video CompressionReducing video data by removing spatial and temporal redundancy and perceptually less important detail.Foundational
- Video ConferencingReal-time two-way or multipoint audio and video communication between participants in different locations.Foundational
- Video Graphics Array (VGA)A legacy analog video connector (DE-15, three rows of 15 pins) for monitors and projectors.Foundational
- Video Matrix SwitcherA device that routes any of multiple video inputs to any of multiple outputs, often with scaling and EDID management.Foundational
- Video SurveillanceUse of cameras (CCTV or IP cameras) to deter, detect, and record physical security events.Foundational
- Video WallMultiple displays or LED modules tiled together and driven by a processor to appear as one large image.Foundational
- ViewA named stored query that behaves like a virtual table; it stores no data and runs its query when referenced.Foundational
- View All and Modify AllObject-level permissions that let users see (or edit and delete) all records of an object regardless of sharing.Intermediate
- View All DataSystem permission allowing a user to view all records across all objects regardless of sharing.Intermediate
- VimA ubiquitous modal text editor on Linux, an improved version of vi, used for editing configuration files.Foundational
- virshThe libvirt command-line tool for managing KVM virtual machines, networks and storage pools.Intermediate
- Virtual AgentServiceNow conversational chatbot that resolves common requests through topics and integrations.Foundational
- Virtual Bluetooth Low Energy (vBLE)Mist technology using a directional BLE antenna array in APs to create virtual beacons for indoor location.Advanced
- Virtual ChassisJuniper technology that interconnects multiple EX or QFX switches to be managed as a single logical device.Intermediate
- Virtual Cloud Network (VCN)OCI software-defined private network in a region, with subnets, route tables, security lists and gateways.Foundational
- Virtual CPU (vCPU)A virtual processor presented to a VM, scheduled by the hypervisor onto physical cores or threads.Intermediate
- Virtual Data Optimizer (VDO)A Linux device-mapper layer providing inline deduplication, compression and thin provisioning for block storage.Advanced
- Virtual Delivery Agent (VDA)The Citrix agent installed on each machine that delivers desktops or applications and registers with Delivery Controllers.Intermediate
- Virtual Desktop Infrastructure (VDI)Hosting desktop operating systems in VMs in the data center or cloud and delivering them to users over a remote display protocol.Foundational
- Virtual Environment (venv)An isolated Python environment with its own interpreter link and installed packages, separate from the system Python.Foundational
- Virtual Extensible LAN (VXLAN)An overlay encapsulation (RFC 7348) that carries Layer 2 frames inside UDP/IP packets, identified by a 24-bit VNI.Intermediate
- Virtual GPU (vGPU)Technology that shares a physical GPU among multiple VMs with time-sliced or partitioned profiles, such as NVIDIA vGPU.Advanced
- Virtual Hard Disk v2 (VHDX)The Hyper-V virtual disk format supporting up to 64 TB, corruption resilience and 4 KB sector alignment.Intermediate
- Virtual Local Area Network (VLAN)A logical Layer 2 broadcast domain created on switches, independent of physical location.Foundational
- Virtual Machine (VM)A software-defined computer with virtual hardware that runs its own operating system on top of a hypervisor.Foundational
- Virtual Machine Disk (VMDK)The VMware virtual disk file format storing a VM's disk contents on a datastore.Foundational
- Virtual Machine Scale Sets (VMSS)Azure compute resource for deploying and automatically scaling a group of load-balanced VMs.Intermediate
- Virtual Machine SnapshotA point-in-time capture of a VM's disk state, and optionally memory, used for short-term rollback.Foundational
- Virtual MemoryAn OS technique that gives each process its own address space backed by RAM and disk storage.Intermediate
- Virtual Network (VN)An SD-Access macro-segment implemented as a VRF across the fabric, isolating groups such as employees, guests and IoT.Advanced
- Virtual Network Computing (VNC)A cross-platform remote desktop system that uses the RFB protocol, typically on TCP port 5900.Intermediate
- Virtual Network PeeringAzure feature that connects two VNets, in the same or different regions, over the Microsoft backbone with private IPs.Intermediate
- Virtual PatchingBlocking exploitation of a known vulnerability with an external control such as a WAF or IPS rule while the code fix is pending.Intermediate
- Virtual Port Channel (vPC)A Cisco Nexus feature that lets a downstream device form one port channel to two separate Nexus switches, which act as a single logical peer.Intermediate
- Virtual Private Cloud (VPC)Logically isolated virtual network in a public cloud where customers define IP ranges, subnets, routing and security controls.Foundational
- Virtual Private LAN Service (VPLS)A multipoint Layer 2 VPN that emulates an Ethernet LAN across an MPLS network using a mesh of pseudowires.Advanced
- Virtual Private Network (VPN)Encrypted tunnel that securely connects remote users or sites across an untrusted network.Foundational
- Virtual Private Wire Service (VPWS)A point-to-point Layer 2 VPN service delivered over pseudowires or EVPN-VPWS.Advanced
- Virtual Router Redundancy Protocol (VRRP)IETF-standard FHRP (RFC 5798 for VRRPv3) with one master and backups sharing a virtual IP that may be a real interface address.Foundational
- Virtual Routing and Forwarding (VRF)A technology that creates multiple independent routing tables on one router so overlapping or separated networks coexist.Intermediate
- Virtual Storage Area Network (VSAN)A Cisco MDS and Nexus feature that partitions a physical Fibre Channel fabric into isolated logical fabrics, each with its own services.Advanced
- Virtual TeamA group of people with shared goals who fulfill roles with little or no time spent meeting face to face.Foundational
- Virtual WarehouseA named cluster of Snowflake compute resources that executes queries and DML; it can be started, stopped and resized independently.Foundational
- VirusMalware that attaches to a host file or program and replicates when that host is executed, requiring user action to spread.Foundational
- VirusTotalA Google-owned online service that scans files, URLs, domains and IPs with many antivirus engines and reputation tools.Foundational
- VishingVoice phishing that uses phone calls or voicemail to manipulate victims into revealing information or taking action.Foundational
- Vision Transformer (ViT)A transformer that processes an image as a sequence of fixed-size patches embedded like tokens.Advanced
- Vision-Language Model (VLM)A model that jointly understands images and text, for tasks such as visual question answering and captioning.Intermediate
- Visual Fault Locator (VFL)A pen-shaped device that shines visible red laser light into a fiber so breaks, tight bends and bad connectors glow visibly.Intermediate
- Visual ManagementLean practice of making work, standards, and abnormalities visible at a glance.Foundational
- Visual, Agile and Simple Threat modeling (VAST)A scalable threat modeling methodology that produces separate application and operational threat models for agile enterprises.Advanced
- VisualforceLegacy tag-based markup framework for building custom pages, using standard or custom Apex controllers.Intermediate
- VLAN HoppingAn attack that sends traffic from one VLAN to another without passing through a router, via switch spoofing or double tagging.Intermediate
- VLAN Trunking Protocol (VTP)A Cisco protocol that propagates VLAN definitions from a server to other switches in the same VTP domain.Intermediate
- VLAN Trunking Protocol PruningA VTP feature that stops flooding of broadcast and unknown traffic for a VLAN across trunks to switches with no ports in that VLAN.Intermediate
- vLLMA popular open-source, high-throughput LLM serving engine built around PagedAttention.Advanced
- VM ConnectorConnector for asynchronous, in-memory or persistent queue communication between flows in an app or domain.Intermediate
- VM TemplateA master copy of a configured VM used to deploy consistent new VMs quickly.Foundational
- VMkernel AdapterA virtual network interface on an ESXi host used for host services such as management, vMotion, storage, vSAN and FT traffic.Intermediate
- vMotionVMware's live migration feature that moves a running VM between ESXi hosts without downtime.Foundational
- vmstatA Linux command reporting virtual memory, process, CPU, paging and I/O statistics at intervals.Intermediate
- VMware Cloud Foundation (VCF)VMware's full-stack private cloud platform integrating vSphere, vSAN, NSX and lifecycle and operations management.Intermediate
- VMware ESXiVMware's Type 1 bare-metal hypervisor, the foundation of VMware vSphere and VMware Cloud Foundation.Foundational
- VMware NSXVMware's network virtualization and security platform providing overlay networking, distributed routing and distributed firewalling.Advanced
- VMware ToolsA suite of drivers and services installed in VMware guest operating systems to improve performance and enable host integration.Foundational
- VMware vCenter ServerThe centralized management server for VMware vSphere that manages ESXi hosts, clusters, VMs and advanced features.Foundational
- VMware Virtual Machine File System (VMFS)VMware's clustered filesystem that lets multiple ESXi hosts concurrently access shared block storage datastores.Intermediate
- VMware vSANVMware's software-defined, hyperconverged storage that pools local disks in ESXi hosts into a shared distributed datastore.Intermediate
- VMware vSphereVMware's server virtualization platform comprising ESXi hosts and vCenter Server with features such as vMotion, HA and DRS.Foundational
- Voice Activity Detection (VAD)A codec feature that stops sending packets during silence to save bandwidth, also called silence suppression.Intermediate
- Voice Class CodecAn IOS list of preferred codecs that a dial peer offers or accepts, in order of preference.Intermediate
- Voice Class TenantA CUBE configuration block that groups SIP settings such as registrar, credentials and bindings for a specific trunk or customer.Advanced
- Voice Class URIA CUBE voice class that matches SIP URIs by host, user or pattern for inbound dial-peer selection.Advanced
- Voice Extensible Markup Language (VoiceXML)A W3C XML language for defining voice dialogs, used by IVR platforms for prompts, speech recognition and DTMF input.Advanced
- Voice GatewayA device that converts between IP telephony signaling and media and TDM or analog interfaces such as PRI, FXO and FXS.Foundational
- Voice of the Customer (VOC)Process of capturing customer needs, expectations, and preferences.Foundational
- Voice over IP (VoIP)Technology that carries voice calls as packets over IP networks instead of traditional circuit-switched lines.Foundational
- Voice QoS RequirementsGuidelines for acceptable voice quality: one-way delay under 150 ms, jitter under 30 ms and packet loss under 1 percent.Foundational
- Voice RouteA Teams Direct Routing object containing a number pattern regex, one or more SBCs and associated PSTN usages.Advanced
- Voice Translation ProfileAn IOS object that groups voice translation rules for calling, called and redirect numbers and is applied to dial peers or trunks.Intermediate
- Voice Translation RuleAn IOS regular-expression rule that rewrites calling or called numbers, applied through a translation profile on dial peers or voice ports.Intermediate
- Voice VLANA separate VLAN on an access port for IP phone traffic, which the phone tags while passing PC traffic untagged.Foundational
- Voice-Activated Switching (VAS)A conference mode that shows the current active speaker full screen and switches as different participants speak.Foundational
- Voicemail PilotThe number in CUCM that routes calls to the voicemail system when users press Messages or calls forward to voicemail.Intermediate
- Voicemail PIN SecurityPolicies that enforce strong voicemail PINs and lockouts to prevent unauthorized mailbox access and toll fraud.Intermediate
- Voicemail ProfileA CUCM setting that ties a directory number to a voicemail pilot and optional voicemail box mask.Intermediate
- VoIP Bandwidth CalculationComputing per-call bandwidth from codec payload, packetization period and Layer 2, IP, UDP and RTP header overhead.Intermediate
- VoIP EavesdroppingIntercepting voice or video traffic, for example by capturing unencrypted RTP and reconstructing the audio.Intermediate
- VoIP NAT TraversalTechniques that allow SIP signaling and RTP media to work across NAT devices that rewrite IP addresses and ports.Intermediate
- VolatilityAn open-source framework for extracting digital artifacts from memory images.Advanced
- Voltage Regulator Module (VRM)Motherboard circuitry that converts 12 V from the PSU into the low voltages needed by the CPU.Advanced
- Voltage Standing Wave Ratio (VSWR)The ratio describing impedance mismatch between transmitter, cable, and antenna; 1:1 is perfect.Advanced
- Volume Group (VG)In LVM, a pool of storage built from one or more physical volumes from which logical volumes are allocated.Intermediate
- Volume Shadow Copy Service (VSS)A Windows framework that coordinates requesters, writers and providers to create consistent point-in-time shadow copies of volumes.Intermediate
- VP8A royalty-free video codec from Google that, along with H.264, is mandatory to implement in WebRTC.Intermediate
- VPC EndpointAWS construct for privately connecting a VPC to supported services without an internet gateway, NAT or public IPs.Intermediate
- VPC Flow LogsFeature that captures metadata about IP traffic going to and from network interfaces in a virtual network.Intermediate
- vPC Peer LinkThe port channel between two vPC peer switches that synchronizes state and carries traffic for orphan ports and flooding.Advanced
- VPC PeeringPrivate networking connection between two virtual networks that routes traffic using private IP addresses.Intermediate
- VPC Service Controls (VPC SC)Google Cloud feature creating service perimeters around Google-managed services to mitigate data exfiltration.Advanced
- VPNv4 Address FamilyThe MP-BGP address family that carries 12-byte VPN-IPv4 routes (RD + IPv4 prefix) and VPN labels between PEs.Advanced
- VRF-LiteUsing VRFs for Layer 3 segmentation without MPLS or MP-BGP, by carrying each VRF on separate interfaces or subinterfaces hop by hop.Intermediate
- vSphere Distributed Resource Scheduler (DRS)A vSphere cluster feature that balances VM workloads across hosts using vMotion and places VMs at power-on.Intermediate
- vSphere Distributed Switch (VDS)A virtual switch managed centrally in vCenter that spans multiple ESXi hosts with consistent configuration.Intermediate
- vSphere Fault Tolerance (FT)A vSphere feature that keeps a live secondary copy of a VM on another host for zero-downtime failover.Advanced
- vSphere High Availability (vSphere HA)A cluster feature that automatically restarts VMs on surviving ESXi hosts after a host failure.Intermediate
- vSphere Lifecycle Manager (vLCM)The vSphere tool that manages ESXi host patching, upgrades and firmware using cluster images or baselines.Intermediate
- vSphere Standard Switch (VSS)A virtual switch configured individually on each ESXi host that connects VMs and VMkernel adapters to physical uplinks.Foundational
- VulnerabilityA weakness in an asset, control, or process that a threat could exploit.Foundational
- Vulnerability AssessmentA systematic process of identifying, quantifying and prioritizing vulnerabilities without attempting to exploit them.Foundational
- Vulnerability Disclosure Policy (VDP)A public policy explaining how external parties can report vulnerabilities and what they can expect in return.Foundational
- Vulnerability ExceptionA formally approved, documented decision to delay or not remediate a vulnerability, usually with compensating controls.Intermediate
- Vulnerability Exploitability eXchange (VEX)A machine-readable advisory stating whether a product is actually affected by a known vulnerability in one of its components.Advanced
- Vulnerability ManagementThe continuous process of identifying, assessing, prioritizing, remediating and verifying security weaknesses.Foundational
- Vulnerability PrioritizationRanking vulnerabilities for remediation based on severity, exploitability, exposure and asset criticality.Intermediate
- Vulnerability Remediation SLAA defined maximum time to fix a vulnerability based on its severity or risk rating.Foundational
- Vulnerability Response (VR)ServiceNow application that imports scanner findings, prioritizes vulnerabilities using CMDB context and drives remediation.Intermediate
- Vulnerability ScanningAutomated testing of systems and applications to identify known vulnerabilities, missing patches and misconfigurations.Foundational
- Vulnerability ValidationConfirming that a reported vulnerability truly exists and that remediation actually fixed it.Intermediate
- Vulnerable and Outdated ComponentsOWASP Top 10 2021 category for using libraries, frameworks or platforms with known vulnerabilities or that are unsupported.Foundational
- Vulnerable Item (VI)Record representing a specific vulnerability detected on a specific CI.Intermediate
- VXLAN BGP EVPNA data center fabric design using VXLAN as the data plane and BGP EVPN as the control plane to distribute MAC and IP reachability.Advanced
- VXLAN Network Identifier (VNI)The 24-bit segment ID in the VXLAN header that identifies a Layer 2 (L2VNI) or Layer 3 (L3VNI) virtual network.Intermediate
- VXLAN Tunnel Endpoint (VTEP)The device or function that encapsulates and decapsulates Layer 2 frames into VXLAN UDP packets at the edge of an overlay.Intermediate