Technical Concepts

Technical products and certification objectives change. The underlying engineering problems change much more slowly. This section teaches those durable models first, then connects them to vendor implementations and exam guides where the differences matter.

Use a concept guide when you want to understand why an architecture or operational choice works. Use a vendor guide when you need product-specific behavior. Use an exam guide when you need to map that knowledge to a current objective list.

How the layers fit together

The concept page is canonical when several vendors or exams share the same model. Product-specific pages should explain real implementation differences rather than repeat the general lesson with different service names.

Published concept clusters

Start with Resilience and Disaster Recovery for availability, durability, failure domains, recovery objectives, backup, replication, failover, and recovery testing.

Continue with Identity and Access Management for authentication, authorization, federation, OAuth, OIDC, SAML, role and attribute models, least privilege, privileged access, workload identity, secrets, access reviews, and zero trust.

Future clusters should be added selectively. A cluster belongs here when it forms a coherent learning path and can support multiple roles, technologies, or certification families without becoming a disconnected encyclopedia entry.

In this section

• Resilience and Disaster Recovery
  Vendor-neutral resilience and disaster recovery guides for availability, failure domains, RTO, RPO, backup, replication, failover, and recovery testing.
  • Availability, Durability, and Recoverability
    Distinguish availability, reliability, durability, recoverability, fault tolerance, and resilience when evaluating a system design.
  • RTO, RPO, and Recovery Objectives
    Define RTO, RPO, maximum tolerable downtime, work recovery time, and measurable recovery objectives for complete business services.
  • High Availability vs Disaster Recovery
    Compare high availability and disaster recovery by failure scope, service continuity, recovery workflow, data protection, cost, and operational evidence.
  • Backup vs Replication
    Choose backup, snapshots, logs, replication, and immutable copies based on outage, corruption, deletion, ransomware, retention, RTO, and RPO requirements.
  • Failure Domains and Blast Radius
    Identify correlated failure domains, hidden shared dependencies, control-plane risks, and blast-radius boundaries in resilient system design.
  • Active-Active and Active-Passive Architectures
    Compare active-active and active-passive architectures across traffic, state, capacity, failover, consistency, split-brain risk, cost, and operations.
  • Disaster Recovery Strategy Patterns
    Select backup-and-restore, pilot-light, warm-standby, hot-standby, or active-active recovery based on RTO, RPO, failure scope, state, cost, and operations.
  • Replication and Consistency Trade-offs
    Understand synchronous and asynchronous replication, quorum, lag, write ownership, conflict resolution, promotion, and the relationship between consistency and RPO.
  • Failover, Failback, and Recovery Testing
    Design safe failover and failback workflows, recovery runbooks, exercises, validation gates, observability, and evidence for tested resilience.
  • Resilience and Disaster Recovery Cheat Sheet
    A vendor-neutral resilience and disaster recovery cheat sheet for RTO, RPO, high availability, backup, replication, standby patterns, failover, and testing.
• Identity and Access Management
  Vendor-neutral identity and access management guides for authentication, authorization, federation, least privilege, privileged access, workload identity, secrets, access reviews, and zero trust.
  • Authentication vs Authorization
    A practical guide to separating identity proof from permission decisions in access-control designs and exam scenarios.
  • Federation and Single Sign-On
    How federation and SSO reduce account sprawl while preserving clear trust, authorization, and lifecycle controls.
  • OAuth, OIDC, and SAML
    A practical comparison of OAuth 2.0, OpenID Connect, and SAML for delegated access, sign-in, and enterprise federation.
  • RBAC, ABAC, and Policy Models
    How role-based, attribute-based, resource-based, and guardrail policies combine in modern access-control systems.
  • Least Privilege
    How to design, test, and maintain least-privilege access without confusing narrow permissions with broken operations.
  • Privileged Access Management
    How to control administrator, break-glass, and sensitive operational access with just-in-time privilege, approval, logging, and review.
  • Workload Identity
    How applications, jobs, containers, and automation authenticate securely without embedded long-term credentials.
  • Secrets, Keys, and Credentials
    How to distinguish passwords, API keys, tokens, encryption keys, certificates, and secrets-management controls.
  • Access Reviews and Lifecycle
    How joiner, mover, leaver, certification, and access-review workflows keep permissions aligned with real business need.
  • Zero Trust Access
    A practical guide to zero trust access decisions using identity, device, context, least privilege, segmentation, telemetry, and continuous evaluation.
  • Identity and Access Management Cheat Sheet
    A vendor-neutral IAM cheat sheet for authentication, authorization, federation, OAuth, OIDC, SAML, least privilege, workload identity, secrets, privileged access, and zero trust.