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Quiz

2707 questions of the kind that actually get asked — in interviews, in architecture review boards, and by the person who has to run the thing at 3 AM. Every answer states the trade-off rather than the slogan, and says when the obvious choice is the wrong one.

All areas2707 Architecture Fundamentals81 Distributed Systems101 Data Architecture90 Cloud Architecture87 Networking86 API & Integration Architecture78 Reliability & Resilience88 Observability81 Performance & Capacity Engineering90 Security Architecture95 Cost Architecture & FinOps92 Business Architecture93 Architecture Communication91 Enterprise Architecture91 Legacy Modernization92 AI-Era Architecture96 Software Architecture & Engineering84 Architecture Patterns84 Architecture Decision-Making91 The Architect's Meta-Skills92 Delivery & Release Engineering93 Platform Engineering & Developer Experience92 Testing & Quality Architecture90 Data Platform Architecture98 Streaming & Real-Time Data93 Data Governance & Semantics91 Frontend & Experience Architecture91 Edge, Mobile & IoT88 Regulatory & Data Protection Architecture90 Assurance, Audit & Model Risk98
Difficulty Any beginner intermediate advanced

63 questions in Edge, Mobile & IoT.

  1. Device Telemetry at Scale advanced

    A fleet platform emits 25 metric series per device, tagged with device id, for 400,000 devices. The observability bill is now larger than the compute bill for the platform itself. The team proposes dropping the device id tag and keeping per-model and per-region aggregates. What does that buy, what does it give up, and when does the bill arrive?

    3 min answer cardinalitytelemetrycostdiagnosis
  2. Device Telemetry at Scale advanced

    A logistics platform receives location updates from a large fleet every few seconds. Where should volume be reduced, and what is the ordering of leverage?

    2 min answer delhiveryportertelemetryfiltering
  3. Device Telemetry at Scale advanced

    A ride-hailing platform receives location updates from hundreds of thousands of active drivers every few seconds. Design the ingest and serving path.

    2 min answer ubergeospatialingestionreal-time
  4. Device Telemetry at Scale advanced

    Design telemetry collection where the volume of monitoring data would cost more than the systems being monitored.

    2 min answer telemetrycardinalitysamplingcost
  5. Digital Twin advanced

    A team proposes a digital-twin platform for 20,000 HVAC units: every sensor reading and every attribute change written to an event-sourced graph database with full per-attribute version history, a rules engine evaluating 400 conditions per device per minute, and a 3D visualisation of each site. The goal is "predictive maintenance and remote diagnostics". Review it. What would you remove, what would you change, and what would you leave alone?

    3 min answer digital-twinover-engineeringreviewstate
  6. Edge Compute Topologies advanced Multiple choice

    A content and application platform must choose between many small points of presence and fewer larger regional sites. What trades off?

    1 min answer edgetopologycachinglatency
  7. Edge Compute Topologies advanced

    A team proposes moving an API to edge functions to reduce latency for international users. What do you check before agreeing?

    2 min answer edgelatencyarchitecturedata
  8. Edge Data Consistency advanced

    A mobility platform wants to place data close to users in many regions. Which data can be replicated and which cannot?

    2 min answer olafly-ioedgereplication
  9. Edge Data Consistency advanced

    A social platform serves user profiles from edge caches worldwide. A user updates their profile and still sees the old one. How should this be handled?

    1 min answer edgeconsistencyinvalidationread-your-writes
  10. Edge Data Consistency advanced

    After a price change you issue a CDN purge and every point of presence returns 200. Twenty minutes later customers in one region still see the old price, and a hard refresh fixes it for some of them. Where do you look and in what order?

    2 min answer cdnpurgecache-variantsvary
  11. Edge Data Consistency advanced

    You enforce a rate limit of 100 requests per minute per user at the edge, across 40 locations. Abuse monitoring shows a user making 3,000. Explain.

    2 min answer edgerate-limitingconsistency
  12. Edge Functions advanced

    Shortly before 10:00 UTC on 8 June 2021 a Fastly customer pushed a valid configuration change and about 85% of the network began returning errors. The bug had shipped on 12 May and lay dormant. Detection took about a minute and 95% of the network was recovered within 49 minutes. What class of failure is this?

    2 min answer fastlyconfigurationlatent-bugblast-radius