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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. 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
  2. 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
  3. Edge Data Consistency intermediate

    Review this design. A streaming platform resolves three things in an edge function on every playback request: the active feature-flag set written from CI and read 200000 times a second; the regional price shown in the paywall; and whether this account's subscription is still active. All three live in a globally replicated edge key-value store with roughly 10-second propagation, writable from any location with last-writer-wins. What would you remove, what would you change, and what would you leave alone?

    3 min answer edge-data-consistencyreplicationentitlementsigned-tokens
  4. 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
  5. Edge Functions advanced

    A checkout read API is deployed as an edge function to 300 points of presence. Global traffic is 60 requests per second and follows population: the busiest location takes about 8% of it and the 150th-busiest takes about 0.1%. The runtime evicts an idle isolate after roughly 30 seconds. Roughly what share of requests at that 150th location pays an initialisation path and what does the number rule in or out?

    4 min answer edge-functionscold-startpoissoncapacity-modelling
  6. Edge Functions intermediate

    A team wants to move logic to edge functions. What are the genuine constraints, and which logic should stay at the origin?

    2 min answer verceledgeconstraintsstate
  7. 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
  8. Edge Functions advanced

    What genuinely belongs in an edge function, and what is the failure mode of putting too much there?

    1 min answer edge-functionsruntime-limitsstatedebugging
  9. Edge Functions advanced

    Which parts of a personalised page would you compute at the edge, and where does each piece of state live?

    2 min answer edgestatecachingpersonalisation
  10. Edge, Mobile & IoT intermediate

    40000 sub-GHz sensors sit under 60 gateways in the European 868 MHz band. A 24-byte configuration change must reach every device. Gateway transmission is bounded by the ETSI EN 300 220 duty cycle - 1% on the sub-band in use - and one downlink frame at the spreading factor in use occupies roughly 150 ms of airtime. Roughly how long does the fleet-wide change take and which assumption would you attack first?

    3 min answer lorawanduty-cycledownlinkfleet-config
  11. Edge, Mobile & IoT advanced

    A VP says the app feels slow in Asia and asks whether the team should move it to the edge. Walk me through how you scope that conversation.

    3 min answer edgelatencytlsscoping
  12. Edge, Mobile & IoT advanced Multiple choice

    A global platform is deciding what to run at the edge, in a regional cloud, and centrally. What determines the placement of each capability?

    1 min answer edgeplacementconsistencylatency