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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. Physical-World Failure Modes beginner Multiple choice

    A courier fleet of 8000 phones sends one location update every 5 seconds while on shift, 8 hours a day. Each update is about 400 bytes on the wire including headers on a reused connection. Roughly how much cellular data is that per device per month?

    3 min answer estimationtelemetrybatterybatching
  2. Physical-World Failure Modes advanced

    A logistics platform's software is correct and the operation still fails regularly. What failure modes does software architecture usually ignore?

    2 min answer physical-worldfailure-modeshuman-factorsdegradation
  3. Physical-World Failure Modes advanced

    A logistics system's software is correct and operations still fail. What class of failure is this, and how should the architecture accommodate it?

    2 min answer porterphysicalexceptionsreconciliation
  4. Physical-World Failure Modes advanced

    A regional power cut takes out 9,000 building-controller devices for six hours. Power returns and 8,700 of them reconnect within ten minutes. The other 300 never come back, and the gateway logs show TLS handshake failures with "certificate is not yet valid". The certificates do not expire for another year. What failed, and which design decision made it possible?

    3 min answer clocktlscold-startfleet
  5. Push & Background Work intermediate

    A courier app relies on a data-only push to trigger a background sync. The push provider's dashboard reports 99.3% delivered. Product reports that about 6% of couriers see stale job lists for hours, and support notices these users are disproportionately on low battery or older devices. Where do you look, in what order, and what is the misleading signal?

    3 min answer pushbackground-workdozebattery
  6. Push & Background Work intermediate

    A mobile app syncs data in the background every 15 minutes. Users report data is frequently out of date. Explain.

    2 min answer mobileos-constraintssync
  7. Push & Background Work intermediate

    A mobile application relies on push notifications and background processing for time-sensitive updates. What is unreliable, and what must the design assume?

    1 min answer zeptopushbackgroundreliability
  8. Push & Background Work advanced

    Design push and background work for a chat application delivering to hundreds of millions of devices.

    2 min answer pushnotificationsfanoutbattery
  9. Push & Background Work advanced

    JioStar reported a peak of 55.2 million concurrent viewers on JioHotstar for the 2025 IPL final. Take a platform of that shape. At the last ball, product wants a "match won" push sent to 120 million installs carrying a deep link into the highlights screen. Video is on a CDN and the API tier is sized for 1.5x the match-time peak. What happens in the first 90 seconds after the send begins and what stops it?

    4 min answer hotstarpush-notificationsthundering-herdfan-out
  10. Sync & Conflict Resolution intermediate Multiple choice

    A delivery app syncs three things from each courier's phone. An availability toggle the courier flips; a cash-collected ledger of per-order amounts; and a per-order delivery status. Couriers go offline for up to an hour in basements and lifts, and a minority have the app installed on two phones. Which conflict policy fits these three fields?

    4 min answer syncconflict-resolutioncrdtsstate-machine
  11. Sync & Conflict Resolution advanced

    A field application has been live for three months and support reports that engineers occasionally lose completed job reports. What do you investigate?

    2 min answer offlinesyncconflictincident
  12. Sync & Conflict Resolution advanced

    A field-service app syncs with a change cursor. Support reports that three customers see cancelled jobs reappearing months after they were closed, and every affected engineer had been on extended leave. The sync endpoint returns 200 for these devices and the client reports no errors. Where do you look, in what order?

    2 min answer synctombstonescursorsretention