Domain 1 – Cloud Computing Concepts & Architectures

Definition of Cloud Computing

NIST (SP 800-145) Defines Cloud Computing :

Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.

Abstraction & Orchestration

Cloud environments rely on abstraction and orchestration to manage resources. For example, abstraction involves creating virtual machines (VM) from physical servers, while orchestration automates and coordinates the provisioning of these VMs and their networking to cloud service customers.

Cloud Computing Models

Cloud Characteristics

Resource Pooling – Resources are pooled, and consumers are granted access. A consumer’s access to the pools is tightly isolated from other consumers’ access. This is typically based on policies set by the provider.

Broad Network Access – Resources are hosted in a cloud environment. They are accessible from a wide range of locations and devices.

Rapid Elasticity – Ability that enables consumers to scale resources based on demand, often automatically.

Measured Service – Measured service simply means that the customer is charged for only what they use and nothing more.

On-demand self-service – On-demand services allow customers to scale their compute and/or storage needs. This requires little or no intervention from the provider. There is also no need for prior communication with the provider. The services happen in real time.

ISO/IEC list 6 characteristics of Cloud computing. 5 characteristics are same as mentioned by NIST. The 6th characteristics is Multi-tenancy

Multi-tenancy – A mode of functioning where multiple individual tenants exist. These tenants, like companies in a public cloud, operate in a shared environment. The tenants are logically isolated but physically integrated.