Introduction to Cloud Computing
Cloud computing delivers computing resources — servers, storage, databases, networking, software, analytics — over the Internet on a pay-as-you-go basis.
Essential Characteristics
NIST defines five: on-demand self-service, broad network access, resource pooling (multi-tenant), rapid elasticity, and measured service (pay for use).
Service Models
IaaS: VMs, storage, networks (AWS EC2, Azure VMs). PaaS: development platforms (Heroku, App Engine). SaaS: ready-to-use apps (Gmail, Salesforce, Microsoft 365).
Deployment Models
Public (AWS, Azure, GCP), private (dedicated), hybrid (combination), community (shared concerns).
Benefits and Challenges
Benefits: cost reduction, scalability, flexibility, global reach. Challenges: security, vendor lock-in, compliance, latency.
Cloud Providers
AWS (largest), Azure (enterprise), GCP (data/ML), IBM, Oracle, Alibaba, DigitalOcean.
Summary
Cloud computing transforms IT from capital to operational expense. IaaS, PaaS, SaaS and deployment models are fundamental concepts.