IT Glossary | Alpha Next Inc.

An introduction to IT terms frequently used in our client discussions, together with our interpretation. For precise definitions, please consult the relevant standards or vendor documentation.

A-D

Access Review: A periodic check that users still need their assigned permissions, helping prevent unnecessary access from remaining after transfers or departures.
API: A set of conventions enabling software systems to exchange functionality and data, forming the basis of system integration.
Assessment: An examination of the current state of systems and networks to identify challenges and improvement options. It informs migration or modernization decisions and is distinct from implementation.
Availability: The extent to which a system remains usable, commonly expressed as uptime or acceptable annual downtime. Higher availability generally costs more, so business requirements should be defined first.
Backup Retention: Keeping copies from multiple points in time so recovery options are clear. Daily, weekly and monthly copies balance retention needs with storage costs.
Bastion Host: A server through which access to internal systems is routed, centralizing connection control and activity recording.
Bottleneck: The component limiting overall performance. Adding resources elsewhere may only increase cost without improving results.
Business Continuity Plan (BCP): A plan for continuing or quickly resuming business after disasters or incidents. IT aspects commonly include backup locations and recovery-time objectives.
CI/CD: A mechanism for automating the integration and delivery of changes, reducing manual work to improve both release frequency and quality.
CSIRT: A team responsible for security incident response within an organization, gathering information in normal operations and coordinating during incidents.
Data Lake: Storage for raw structured and unstructured data. It allows uses to be decided later, but can grow without delivering value unless there is a clear organization strategy.
Data Silos: A situation where data or processes are isolated within departments or systems, preventing cross-organizational use. Organizational factors are often as important as technical ones.
Disaster Recovery (DR): Preparations for recovering from major disruption, including disasters, typically involving remote replication and documented failover procedures.
Downtime: A period during which a system is unavailable, managed separately for planned and unplanned outages.

E-H

EDR: A mechanism that records and analyzes endpoint activity to detect suspicious behavior after intrusion, used alongside preventive controls.
Escalation: Referring an issue beyond an operator's authority or knowledge to a senior colleague or specialist team. Clear escalation criteria help avoid delayed decisions.
Failover: Automatically transferring processing to a standby system when a failure is detected. Its effectiveness should be confirmed through practical testing.
Government Cloud: A cloud environment intended for shared use by Japanese government agencies and municipalities, serving as a foundation for standardizing local-government information systems.

I-L

IaC（Infrastructure as Code）: Describing server and network configurations as code so environments can be reproduced, reducing reliance on individuals' configuration knowledge.
Identity Provider (IdP): A service that authenticates users and passes verification results to other services, forming a central part of single sign-on.
Immutable Backup: A backup configured so that it cannot be changed or deleted after creation, intended to prevent ransomware from encrypting the backup alongside production data.
Incident Response: The response to a security incident, from detection and containment through recovery and prevention of recurrence. Procedures and contact arrangements should be established in advance.
IT Asset Inventory: Identifying live servers, software and contracts, and checking their purpose and utilization. It is a prerequisite for migration planning and often one of the most time-consuming steps.
Load Testing: Testing expected usage levels to assess performance limits and behavior. Results are meaningful only when test conditions resemble production.

M-P

MDM: A mechanism for centrally managing business-device settings, applications and responses to device loss.
Monitoring Point: A target from which monitoring measurements are collected to detect abnormal conditions. Too many points can bury useful alerts; too few can leave incidents undetected.
Multifactor Authentication (MFA): Identity verification using more than one factor, such as a password, a device or biometrics. It is a basic measure for limiting harm when a password is compromised.
Observability: The extent to which a system's internal state can be inferred from logs, metrics and traces. Unlike basic monitoring, it aims to help investigate causes of unexpected failures.
On-premises: Running systems on equipment owned and managed by the organization itself, a term commonly used in contrast to cloud services.
Penetration Testing: Testing defenses by attempting intrusion from an attacker's perspective. Its purpose differs from an assessment that simply lists vulnerabilities.
Phased Migration: Moving parts of a system in stages rather than switching everything at once. It can reduce downtime, but requires old and new environments to run in parallel during migration.
Privileged Account: An administrator identity able to change system settings or access extensive data. Its users and access times should be limited, and activity should be recorded.

Q-T

Recovery Point Objective (RPO): The acceptable point in time to which data may be restored after an incident, used to determine backup frequency.
Recovery Time Objective (RTO): The target maximum time from an incident to recovery. Shorter objectives increase infrastructure and operational costs, so they should reflect business impact.
Redundancy: Providing multiple devices or paths with the same function so service can continue when one fails. The extra cost should be weighed against the business impact of an outage.
Responsibility Boundary: The division of responsibilities between provider and customer. In cloud services, it is important to understand which controls the provider manages and which remain with the customer.
SBOM: An inventory of software components, such as libraries, used to identify affected systems quickly when vulnerabilities are disclosed.
Scale Out / Scale Up: Two ways to increase capacity: scaling out adds more machines, while scaling up increases the power of an individual machine. The appropriate approach depends on system architecture.
Security Operations Center (SOC): An organization or function responsible for security monitoring and initial incident response, operated either internally or by an external provider.
Service Level Agreement (SLA): An agreement defining service quality through measures such as uptime and response time, normally including arrangements for when those commitments are not met.
SIEM: A mechanism that collects logs from devices and systems and correlates them to detect potential threats. Detection rules require ongoing tuning after deployment.
Single Sign-on (SSO): A mechanism allowing access to multiple systems after one authentication. It improves convenience and makes access management easier by centralizing authentication.
Sizing: Estimating required processing power and capacity to determine resource allocation. Excess capacity wastes money; insufficient capacity creates performance problems.
SRE: An engineering approach to operations that defines objectives and balances delivery speed with reliability within those limits.
Targeted Attack: An attack aimed at a particular organization, often using emails that imitate business communications and are tailored using prior research.

U-Z

Virtual Desktop Infrastructure (VDI): Running a user's desktop environment on servers and transmitting the display to the endpoint, allowing designs that leave no business data on the device.
Virtualization: Technology that runs multiple independent server environments on one physical server to improve equipment utilization. It was widely used before cloud adoption.
WAF: A mechanism that inspects web-application traffic and blocks requests identified as attacks. It can also mitigate risk when application changes are difficult.
Zero Trust: An approach that verifies users, devices and conditions for each access request, without automatically trusting connections inside the corporate network. It contrasts with designs based primarily on perimeter defenses.

49 terms. Last updated: August 2026.