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

6 questions in Edge, Mobile & IoT.

Quiz

A metered NB-IoT fleet must not record a reading twice, because readings drive a customer's bill. The team proposes QoS 2 so the broker delivers each publish exactly once. Which choice fits better?

A gateway requires each device to prove it is running approved firmware. The device sends a signed measurement of its boot image, and the gateway verifies the signature against the device's registered key. Why is a valid signature not yet evidence that this device is trustworthy right now?

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?

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?

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?

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?