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Quiz

2827 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 areas2827 Architecture Fundamentals91 Distributed Systems101 Data Architecture90 Cloud Architecture87 Networking86 API & Integration Architecture87 Reliability & Resilience99 Observability92 Performance & Capacity Engineering90 Security Architecture95 Cost Architecture & FinOps92 Business Architecture93 Architecture Communication91 Enterprise Architecture100 Legacy Modernization92 AI-Era Architecture96 Software Architecture & Engineering93 Architecture Patterns84 Architecture Decision-Making101 The Architect's Meta-Skills92 Delivery & Release Engineering103 Platform Engineering & Developer Experience92 Testing & Quality Architecture102 Data Platform Architecture98 Streaming & Real-Time Data93 Data Governance & Semantics91 Frontend & Experience Architecture101 Edge, Mobile & IoT98 Regulatory & Data Protection Architecture99 Assurance, Audit & Model Risk98
Difficulty Any beginner intermediate advanced

98 questions in Edge, Mobile & IoT.

  1. IoT Ingest Architecture advanced

    After a five-minute network outage at your ingest tier, 200,000 devices reconnect simultaneously and the authentication service collapses. How do you fix this?

    2 min answer iotthundering-herdresiliencescale
  2. IoT Ingest Architecture advanced

    Design ingestion for millions of devices sending telemetry continuously over unreliable networks.

    1 min answer iotingestprotocolsbackpressure
  3. IoT Ingest Architecture advanced

    Two million devices reconnect simultaneously after a network partition. What happens and what prevents it?

    2 min answer reconnection-stormbackpressurejitteringest
  4. IoT Ingest Architecture advanced

    WeChat's DAGOR overload control (SoCC 2018) sheds load using the time requests spend queued inside a service rather than response time, and drops by business and user priority. How would you apply that to a device-fleet ingest tier, and what must the device do for it to work?

    3 min answer wechatdagoradmission-controlbackpressure
  5. Mobile App Architecture beginner Multiple choice

    A delivery app marks a parcel delivered. The phone is on a weak connection: the request reaches the server, the response is lost, and the app retries. The customer is charged twice and the parcel is marked delivered twice. Which change fixes this properly?

    2 min answer idempotencyretriesmobileat-least-once
  6. Mobile App Architecture beginner

    A mobile client stamps each event with its own clock and the server stores that timestamp. Why does this break reporting and de-duplication, and what should the server record instead?

    2 min answer clocksevent-timeidempotencyoffline
  7. Mobile App Architecture advanced

    Alibaba reported a peak of 583,000 order-creation requests per second during the 2020 Singles' Day festival on 11 November. Demand of that shape is produced by a countdown every client sees at the same instant. What does scheduled demand change about the mobile client's responsibilities, and where would copying the approach be a mistake?

    3 min answer alibabaflash-salemobileadmission-control
  8. Mobile App Architecture advanced

    Design the mobile architecture for a ride-hailing app used on poor networks, in the background, with continuous location updates.

    2 min answer mobileofflinebatterybackground
  9. Mobile App Architecture advanced

    What changes about API design when your clients cannot be upgraded?

    2 min answer mobileversioningserver-drivenadditive
  10. Mobile Release Strategy beginner Multiple choice

    A mobile app ships a release with a defect that crashes on launch for users in one country. The team is confident because the release included a remote kill switch for the new feature. It does not help. Which mistake does this most likely reflect?

    3 min answer kill-switchfeature-flagsmobilestartup
  11. Mobile Release Strategy advanced

    A mobile application cannot be updated instantly and a bad release is in the store. What should the architecture provide?

    2 min answer physics-wallahmobilefeature-flagsrollout
  12. Mobile Release Strategy advanced

    A mobile team adopts server-driven UI so screens can change without an app release. What have they bought, and when does the bill arrive?

    2 min answer server-driven-uimobilecompatibilityrelease