Azure IoT and DevOps Services
Key Takeaways
- Azure IoT Hub is the PaaS message broker for secure two-way communication with millions of devices over MQTT, AMQP, or HTTPS.
- Azure IoT Central is a fully managed SaaS app that delivers dashboards, device templates, and rules with no infrastructure to run.
- Azure IoT Edge pushes cloud logic and AI onto devices so they keep working offline and process data locally.
- Azure DevOps has five services: Repos (Git), Pipelines (CI/CD), Boards (Agile tracking), Artifacts (package feeds), and Test Plans.
- GitHub Actions provides CI/CD inside GitHub; DevTest Labs gives cost-controlled dev/test environments with auto-shutdown.
Quick Answer: IoT Hub = PaaS device message broker (full control). IoT Central = SaaS IoT app (no code, no infrastructure). IoT Edge = run cloud logic on the device, even offline. Azure DevOps = Repos + Pipelines + Boards + Artifacts + Test Plans. GitHub Actions = CI/CD inside GitHub. DevTest Labs = managed dev/test sandboxes with cost caps.
The Azure IoT trio — and the one distinction that matters
The exam almost always tests IoT Hub (PaaS) vs. IoT Central (SaaS). Read for the level of control and effort:
| Service | Cloud model | Effort | Choose when the scenario says... |
|---|---|---|---|
| IoT Hub | PaaS | High control, more setup | "custom solution", "full control", "build my own dashboards/back end" |
| IoT Central | SaaS | Low/no code | "fastest to deploy", "no infrastructure to manage", "built-in dashboards and rules" |
| IoT Edge | Device runtime / extension | Medium | "process data on the device", "keep working offline", "reduce data sent to cloud" |
Azure IoT Hub
Azure IoT Hub is the managed cloud gateway every device connects to. It supports device-to-cloud telemetry and cloud-to-device commands, per-device authentication (each device has its own identity and key), and millions of simultaneous connections. Supported protocols are MQTT, AMQP, and HTTPS. IoT Hub does not give you dashboards; you route its messages to Storage, Event Hubs, or Functions and build the rest yourself — which is exactly why it is the PaaS, full-control answer.
Azure IoT Central
Azure IoT Central is a finished SaaS application sitting on top of IoT Hub. You connect devices using device templates, get dashboards, rules and alerts, and user management without writing code or running servers. It is the answer whenever the priority is speed and simplicity over customization.
Azure IoT Edge
Azure IoT Edge deploys containerized modules — including trained AI models and Azure services — down onto the device. The device then filters, aggregates, or scores data locally and can keep operating while disconnected from the cloud. Pick it when the scenario stresses low latency, offline operation, or sending only summarized data upstream (saving bandwidth).
Worked example: A remote oil rig with intermittent connectivity must run anomaly detection on sensor data even when the satellite link drops. IoT Edge (running the model on-site) is correct; IoT Hub alone would stop scoring when offline.
Azure DevOps — the five services
Azure DevOps is Microsoft's suite for planning, building, testing, and shipping software. Memorize all five and what each does:
| Service | Purpose |
|---|---|
| Azure Repos | Private, unlimited Git repositories for source control |
| Azure Pipelines | CI/CD to build, test, and deploy automatically |
| Azure Boards | Agile work tracking — Kanban boards, backlogs, sprints, work items |
| Azure Artifacts | Package feeds for NuGet, npm, Maven, and Python (pip) |
| Azure Test Plans | Planned and exploratory manual + automated testing |
Trap: Pipelines is the CI/CD answer, not Repos. Repos only stores code; Pipelines does the automated build-test-deploy. Distractors often swap these.
GitHub and Azure
Microsoft owns GitHub, so Azure integrates tightly with it:
- GitHub Actions — workflow-based CI/CD that can deploy straight to Azure; the GitHub-native counterpart to Azure Pipelines.
- GitHub Advanced Security — code scanning, secret scanning, and dependency review.
- GitHub Codespaces — cloud-hosted development environments in the browser.
A common scenario mixes them: teams keep code in GitHub and run releases through Azure Pipelines or GitHub Actions — both are valid CI/CD choices.
Why the PaaS-vs-SaaS framing keeps appearing
The IoT services are a clean illustration of the cloud service models you learned in Domain 1, which is exactly why the exam returns to them. IoT Hub is PaaS: Microsoft runs the broker, but you assemble the rest of the solution — storage, analytics, dashboards — yourself, trading effort for control. IoT Central is SaaS: Microsoft runs the entire application and you only configure it, trading control for speed. When a stem emphasizes least administrative effort or fastest time to value, the SaaS answer (IoT Central) wins; when it emphasizes full customization or integrating with my own back end, the PaaS answer (IoT Hub) wins.
Note too that IoT Central is built on top of IoT Hub, so they are complementary, not competitors.
The same effort-versus-control lens applies to the developer tooling. Azure DevOps and GitHub overlap heavily, and a frequent question asks which to recommend. Both can host code and run CI/CD; the practical guidance Microsoft teaches is that GitHub is favored for open-source and modern developer communities, while Azure DevOps offers the broadest enterprise project-management surface through Boards and Test Plans. Many real teams combine them — code in GitHub, releases through Azure Pipelines or GitHub Actions — and the exam accepts that hybrid as valid.
Do not over-think it: if the choice is purely CI/CD automation, either Pipelines or GitHub Actions is correct, and Repos is never the CI/CD answer.
Azure DevTest Labs
Azure DevTest Labs spins up cost-controlled dev/test environments. Exam-relevant features:
- Auto-shutdown schedules to stop VMs after hours (cuts cost).
- Cost limits and quotas per lab.
- Claimable VMs pre-provisioned and ready for any developer to grab.
- Custom images and formulas so every new VM starts with the right tools.
On the Exam: For IoT, the decision is almost always PaaS control (IoT Hub) vs. SaaS simplicity (IoT Central), with IoT Edge for offline/local processing. For DevOps, recall the five services and that Pipelines (or GitHub Actions) is CI/CD, while Repos is just source control.
A manufacturer wants the fastest possible way to connect devices, view dashboards, and configure alert rules without running any servers or writing code. Which service fits?
Which Azure DevOps service is responsible for continuous integration and continuous deployment (CI/CD)?
A wind farm in a remote area loses its network link for hours at a time but must keep running anomaly detection on sensor readings during outages. What should the solution use?