REFERENCE LIBRARY

The Cloud Glossary.

Straight definitions for the terms that shape cost, compliance, and resilience decisions, written the way we'd explain them in a client conversation, not lifted from a vendor dictionary.

search

Recovery Time Objective (RTO)

The maximum acceptable length of time your systems can be down after a failure before the impact becomes unacceptable to the business.

Resilience & DRRead Definition
timereast

Recovery Point Objective (RPO)

The maximum acceptable age of files or data that must be recovered from backup storage for normal operations to resume after a disaster.

Resilience & DRRead Definition
historyeast

AWS Savings Plans

A flexible pricing model offering discounts up to 72% on AWS compute usage in exchange for a commitment to a consistent hourly spend.

Cost & BillingRead Definition
savingseast

Reserved Instances (RIs)

A billing discount applied to predictable, steady-state EC2 or database instances in exchange for a 1-year or 3-year term commitment.

Cost & BillingRead Definition
account_balance_walleteast

Replatforming (Lift, Tinker, and Shift)

Moving applications to the cloud with targeted optimisations, such as swapping self-hosted databases for managed services, without changing core code.

Migration & ArchitectureRead Definition
cloud_synceast

AWS Landing Zone

A well-architected, multi-account AWS environment configured with baseline security, identity, logging, and networking controls.

Migration & ArchitectureRead Definition
domaineast

AWS Well-Architected Framework

A set of principles and best practices across six pillars used to evaluate and refine cloud architectures for security and performance.

Compliance & RiskRead Definition
verified_usereast

AWS Shared Responsibility Model

The division of security and compliance duties: AWS manages security OF the cloud, while the customer manages security IN the cloud.

Compliance & RiskRead Definition
gaveleast

On-Demand Pricing

AWS's default pay-as-you-go pricing model, billed by the second or hour with no upfront commitment and no long-term contract.

Cost & BillingRead Definition
bolteast

Rightsizing

The practice of matching compute, storage, and database instance sizes to actual workload demand, rather than to initial estimates or default configurations.

Cost & BillingRead Definition
straighteneast

Data Transfer Costs

Charges incurred when data moves out of AWS, between AWS regions, or between certain services: one of the least visible and most commonly underestimated line items on an AWS bill.

Cost & BillingRead Definition
swap_horizeast

Idle & Orphaned Resources

Provisioned infrastructure, such as unattached storage volumes, old snapshots, or unused Elastic IPs, that continues to be billed after the workload it supported has been removed or scaled down.

Cost & BillingRead Definition
delete_sweepeast

AWS Cost Explorer

AWS's native tool for visualising, filtering, and forecasting spend across accounts, services, and tags over time.

Cost & BillingRead Definition
query_statseast

Instance Family

The category of EC2 instance types, such as compute-optimised, memory-optimised, or storage-optimised, each priced and performance-tuned for a different workload profile.

Cost & BillingRead Definition
memoryeast

PCI-DSS

The Payment Card Industry Data Security Standard: a set of security requirements for any organisation that stores, processes, or transmits cardholder data.

Compliance & RiskRead Definition
credit_cardeast

DORA (Digital Operational Resilience Act)

An EU regulation requiring financial entities and their critical ICT providers to demonstrate operational resilience, incident reporting, and third-party risk management.

Compliance & RiskRead Definition
shieldeast

FCA Operational Resilience Requirements

UK Financial Conduct Authority rules requiring regulated firms to identify important business services and set impact tolerances for disruption, including from cloud infrastructure.

Compliance & RiskRead Definition
account_balanceeast

ISO 27001

An international standard for information security management systems, used to demonstrate that security risk is being identified and managed systematically, not ad hoc.

Compliance & RiskRead Definition
securityeast

Cyber Essentials Plus

A UK government-backed certification verifying that basic technical security controls, such as patching, access control, and malware protection, are correctly implemented and independently tested.

Compliance & RiskRead Definition
verifiedeast

GDPR

The UK/EU General Data Protection Regulation, governing how personal data is collected, stored, processed, and protected, including where that data resides in the cloud.

Compliance & RiskRead Definition
policyeast

Cutover

The point in a migration at which production traffic is switched from the old environment to the new AWS environment, typically the highest-risk moment in the whole project.

Migration & ArchitectureRead Definition
swap_horizeast

Rollback

A pre-planned procedure for reverting to the original environment if a migration cutover fails or introduces unacceptable issues in production.

Migration & ArchitectureRead Definition
undoeast

Lift and Shift (Rehosting)

Moving an application to AWS with minimal or no changes to its architecture: the fastest migration approach, and often the most expensive to run long-term.

Migration & ArchitectureRead Definition
flight_takeoffeast

Migration Strategies (The 6 Rs)

The six standard approaches to moving a workload to AWS: Rehost, Replatform, Repurchase, Refactor, Retire, and Retain, each trading off speed, cost, and long-term fit differently.

Migration & ArchitectureRead Definition
hubeast

IAM (Identity and Access Management)

AWS's service for controlling who, and what, can access which resources, forming the security foundation of every account and every migration.

Migration & ArchitectureRead Definition
keyeast

Failover

The automatic or manual process of switching operations to a standby system when the primary system becomes unavailable.

Resilience & DRRead Definition
sync_alteast

Warm Standby

A disaster recovery strategy that keeps a scaled-down but fully functional version of the production environment running at all times, ready to scale up on failover.

Resilience & DRRead Definition
hourglass_topeast

Multi-Region DR

A disaster recovery approach that maintains infrastructure in a geographically separate AWS region, protecting against outages that affect an entire region rather than a single availability zone.

Resilience & DRRead Definition
publiceast

Runbook

A documented, step-by-step procedure for executing a specific operational task, most critically failover and recovery, so it doesn't depend on one person's memory under pressure.

Resilience & DRRead Definition
menu_bookeast

Air-Gapped Backup

A backup copy stored in an isolated environment with no direct network connection to production, protecting it from being encrypted or deleted alongside the systems it's backing up.

Resilience & DRRead Definition
lockeast

Ransomware Recovery

The specific disaster recovery planning required to restore systems after a ransomware incident, distinct from recovery planning for infrastructure failure alone.

Resilience & DRRead Definition
gpp_maybeeast