Data & Connectivity

Introduction

This topic covers two connected ideas: data at a scale far beyond anything a single spreadsheet could hold, and the everyday physical devices now generating much of it.

Concept

• Big Data — datasets too large, too fast-changing, or too varied in structure for traditional tools (like a single spreadsheet or a small database) to handle effectively. Commonly described by three properties: Volume (sheer amount), Velocity (speed of generation), and Variety (different formats and structures mixed together).
• Internet of Things (IoT) — everyday physical objects (a thermostat, a fitness band, a refrigerator) fitted with sensors and internet connectivity, so they can collect and exchange data automatically, without a person directly operating them.

Explanation

IoT and Big Data feed each other directly: a single smart device generates a small amount of data, but millions of connected IoT devices worldwide, all reporting continuously, is precisely the kind of high-Volume, high-Velocity data stream that qualifies as Big Data — IoT is one of the biggest real-world sources of Big Data today, not two unrelated topics that happen to appear together.

Note: The "Three Vs" — Volume, Velocity, Variety — are the standard, exam-relevant way to characterise Big Data specifically; a dataset only needs to be extreme along one or more of these, not necessarily all three, to qualify.

Summary

Big Data describes datasets too large, fast, or varied for traditional tools, commonly characterised by Volume, Velocity, and Variety. IoT connects everyday physical devices to the internet so they can collect and exchange data automatically — and is itself one of the largest real-world sources of Big Data.

The Characteristics (The 3 Vs):

For an exam answer, you must mention the "Vs" of Big Data.

Introduction

This closing topic of the unit — and the course — covers where data and computing power increasingly live today, and a newer way of recording data that no single party controls.

Concept

• Cloud Computing — using computing resources (storage, processing power, software) delivered over the internet from a remote provider, rather than relying only on your own local device.
• Blockchain — a record of data (a "ledger") maintained as a chain of linked entries, copied across many independent computers at once, rather than stored in one central place — making it extremely difficult for any single party to alter past entries unnoticed.

Explanation

Cloud Computing and Blockchain both move data and computing away from a single local machine, but for genuinely different reasons: Cloud Computing centralises resources at a large, remote provider for convenience, scale, and access from anywhere; Blockchain deliberately decentralises a record across many independent parties specifically so no single one of them can control or secretly alter it — one concentrates trust in a provider, the other is built to need no single trusted party at all.

Note: A cloud storage service (a single company's remote servers) and a blockchain (data copied across many independent parties) solve different problems — don't treat them as two names for the same idea just because both move data off a single local device.

Summary

Cloud Computing delivers computing resources over the internet from a remote provider instead of a local device. Blockchain maintains a record as a linked chain copied across many independent computers, making it hard for any one party to alter unnoticed — centralising convenience versus decentralising trust are the key difference between the two.

Service Models (IaaS, PaaS, SaaS):

This is a guaranteed exam question. You must know the difference.