Cloud (Cloud Computing)

What is cloud computing?

Cloud computing refers to the delivery of IT resources as on-demand services rather than on-premises infrastructure. Instead of owning and maintaining physical hardware, organizations consume computing power, storage, and applications from cloud providers via the internet. Cloud services are designed to be scalable, elastic, and usage-based.

Why cloud matters

Cloud computing is critical because it:

• Enables rapid provisioning and scalability
• Reduces upfront capital expenditure (CapEx)
• Improves agility and time-to-market
• Supports global availability and resilience
• Powers modern digital services and applications

For many organizations, the cloud is now the default IT platform.

Cloud service models

Cloud services are typically categorized as:

1) IaaS (Infrastructure as a Service)

• Virtual machines, networks, and storage

2) PaaS (Platform as a Service)

• Managed runtimes, databases, and development platforms

3) SaaS (Software as a Service)

• Fully managed applications delivered via the web

Each model offers a different balance of control and responsibility.

Cloud deployment models

Cloud environments can be deployed as:

• Public cloud – shared provider infrastructure
• Private cloud – dedicated or on-premises cloud
• Hybrid cloud – mix of on-premises and cloud
• Multi-cloud – multiple cloud providers

The choice depends on security, compliance, and business needs.

Cloud and virtualization

Virtualization is a foundational technology for cloud computing:

• Hypervisors enable resource sharing and isolation
• Virtual networks and storage abstract physical infrastructure
• Automation orchestrates resources at scale

Cloud platforms extend virtualization with self-service and automation.

Cloud security considerations

Cloud security introduces shared responsibility:

• Providers secure the underlying infrastructure
• Customers secure configurations, identities, and data

Key security areas include:

• Identity and access management
• Network segmentation and firewalls
• Data protection and encryption
• Logging, monitoring, and compliance

Misconfigurations are a leading cause of cloud breaches.

Cloud and Zero Trust

Cloud environments align naturally with Zero Trust principles:

• Identity-based access replaces network trust
• Continuous verification and least privilege
• Device and risk-aware policies
• Microsegmentation and service-level controls

Zero Trust helps reduce the blast radius of cloud incidents.

Cloud benefits and trade-offs

Benefits

• Elastic scalability
• Global reach
• Managed services
• Faster innovation

Trade-offs

• Vendor lock-in
• Cost visibility and optimization challenges
• Data residency and compliance concerns
• Dependency on provider availability

Common misconceptions

• "Cloud is less secure than on-premises"
• "The cloud provider handles all security"
• "Cloud eliminates downtime risk"
• "Cloud automatically reduces costs"