Cloud Computing

Cloud computing delivers computing resources—servers, storage, databases, networking, software, and analytics—over the internet on demand. Instead of keeping data and applications on local hardware, users and organizations access them from remote, provider-managed servers, enabling flexibility, scalability, and faster deployment.

Key takeaways

• Cloud services are delivered on demand and typically billed by usage or subscription.
• Three primary service models: Software-as-a-Service (SaaS), Infrastructure-as-a-Service (IaaS), and Platform-as-a-Service (PaaS).
• Deployment models include public, private, and hybrid clouds, each offering different trade-offs in control and cost.
• Benefits include cost savings, scalability, and faster time to market; risks include security, outages, and compliance challenges.

How cloud computing stores and manages data

Cloud providers host data and applications on remote servers in data centers. Users access those resources via the internet from any device. Providers manage the underlying infrastructure—hardware, networking, and often security—while customers consume services at different responsibility levels depending on the service model.

Deployment options:
* Public cloud: Shared infrastructure operated by third-party providers and available to multiple customers (e.g., AWS, Azure).
* Private cloud: Dedicated infrastructure operated for a single organization, on-premises or hosted.
* Hybrid cloud: Combines public and private clouds, enabling workload portability and flexible data placement.

Common cloud uses:
* Email and collaboration (e.g., Google Workspace, Microsoft 365)
* Storage, backup, and disaster recovery
* Application development and testing
* Data analytics and machine learning
* Streaming media and content delivery
* On-demand software delivery

Service models: SaaS, IaaS, PaaS

Software-as-a-Service (SaaS)
SaaS delivers complete applications over the internet. Users access software via web browsers or apps without managing infrastructure or runtime environments. Typical pricing is subscription-based.
– Examples: Google Workspace, Microsoft 365, Salesforce.

Infrastructure-as-a-Service (IaaS)
IaaS provides virtualized compute, storage, and networking resources on demand. Customers manage operating systems and applications while the provider handles the physical infrastructure.
– Examples: AWS EC2, Microsoft Azure Virtual Machines, IBM Cloud.

Platform-as-a-Service (PaaS)
PaaS supplies a development and deployment platform with managed runtime, middleware, and tools, letting developers build and deploy applications without managing servers.
– Examples: Heroku, Google App Engine, Red Hat OpenShift.

Benefits

• Cost efficiency: Reduce capital expenditure on hardware; pay-as-you-go pricing.
• Scalability: Quickly scale resources up or down to match demand.
• Faster deployment: Provision services and applications rapidly.
• Accessibility: Access data and apps from any internet-connected device.
• Reduced maintenance: Providers handle hardware, upgrades, and many operational tasks.
• Innovation enablement: Easier experimentation with analytics, AI, and new services.

Risks and limitations

• Security and privacy: Sensitive data stored off-site increases exposure; requires strong encryption, access controls, and compliance measures.
• Downtime and outages: Provider outages or data-center disruptions can affect availability.
• Vendor lock-in: Migrating between providers can be complex and costly.
• Regulatory and compliance constraints: Certain data may require on-premises storage or specific controls.
• Shared responsibility: Security responsibilities are divided between provider and customer—misconfigurations can create vulnerabilities.
• Propagation of errors: Mistakes or malicious actions can impact many users on shared platforms.

Cloud security fundamentals

Protecting cloud resources typically involves:
* Encryption (at rest and in transit)
* Strong identity and access management (IAM), including multi-factor authentication (MFA)
* Network protections: VPNs, firewalls, and private networking
* Monitoring, logging, and intrusion detection
* Data backup, replication, and disaster recovery plans
* Compliance controls and periodic audits

Leading cloud providers

Major providers offer a wide range of services and global infrastructure:
* Amazon Web Services (AWS)
* Microsoft Azure
* Google Cloud Platform (GCP)
* IBM Cloud
* Alibaba Cloud
* Oracle Cloud

Each provider has strengths—some focus on enterprise hybrid solutions, others on AI/analytics, global scale, or specific regional coverage.

Example in practice

A company can use cloud services to host its customer database on a managed database service (IaaS/PaaS), run its web application on PaaS, and use SaaS tools for email and collaboration. During peak demand, it scales compute resources automatically, paying only for what it uses.

Conclusion

Cloud computing centralizes computing resources and delivers them over the internet, enabling organizations and individuals to reduce costs, scale rapidly, and accelerate innovation. Choosing the right service and deployment model requires balancing cost, control, security, and compliance needs. Properly managed, the cloud is a powerful platform for modern IT and digital transformation.