Edexcel 1CP2 · Topic 4 · 4.5a

Cloud
Computing

IaaS · SaaS · PaaS · Advantages & Disadvantages · Security Concerns

CSZoneEdexcel GCSE Computer Science 1CP2

What is Cloud Computing?

Computing as a Service

Cloud computing means using remote servers hosted on the internet to store, manage, and process data instead of using your own local hardware. Services are accessed via a web browser or app and delivered on-demand, typically on a pay-as-you-go basis.

SaaS (Software as a Service): use software over the internet — e.g. Google Docs, Microsoft 365, Gmail

PaaS (Platform as a Service): development platform in the cloud — e.g. Google App Engine, Heroku

IaaS (Infrastructure as a Service): rent virtual hardware — e.g. Amazon AWS, Microsoft Azure

Advantages of Cloud Computing

Why Use the Cloud?

Accessibility: access files from any device, anywhere, with an internet connection

Scalability: easily scale storage and processing power up or down — no need to buy new hardware

Cost: no upfront hardware costs; pay only for what you use; maintenance handled by provider

Automatic backups and disaster recovery provided by the cloud provider

Collaboration: multiple users can work on the same file simultaneously in real time

Disadvantages of Cloud Computing

The Trade-offs

Internet dependency: no internet connection = no access to data or services

Security & privacy: data held by a third party — risk of breaches; concerns over who can access it

Ongoing costs: subscription fees can exceed hardware costs over time

Loss of control: you depend on the provider's uptime, policy changes, and terms of service

Latency: response times over the internet may be slower than local processing

Exam Practice

Have a go at this question

Edexcel-style question

Give two advantages and one disadvantage of a school using cloud storage for students' work.

3 marks

Students can access their work from home or any device [1]; files are automatically backed up so work is not lost if a device is lost or damaged [1]. Disadvantage: if the internet is unavailable, students cannot access their work [1].

Key Takeaways

What to Remember

SaaS: use software online; PaaS: develop in the cloud; IaaS: rent virtual hardware

Advantages: accessible anywhere, scalable, cost-effective, collaboration, auto-backups

Disadvantages: internet dependency, security/privacy concerns, ongoing costs, loss of control

For Edexcel exams: always weigh up advantages vs disadvantages in context of the scenario given