Cloud Computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (for example network, servers, storage, applications and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.
Formal definition of Cloud computing as proposed by NIST (National Institute of Standards and Technology)
** Cloud technology is not a new Technology. Cloud Computing is a new Business Model.
Why do we need to take up cloud computing in the first place?
- Increased and constant need for Capital Investment
- Server Sprawl
- Rising Operational Costs
- Ballong Energy Costs and Demands
- Increased complexity of systems and the need for specialised talent to support them
- Variable resource usage
- Demand for business process simplification
- Time to market pressure.
Cloud Computing Components
- Front end
- It is the part seen by the client, i.e., the computer user.
- It includes the client’s network (or computer) and the applications used to accesss the cloud through user interface such as a web browser.
- Client computers – mobile, think/thick computers
2. Back end
- Back end is the ‘cloud’ itself, comprising various computers, servers and data storage devices.
- Server farm (distributed servers)
- Storage farm (distributed storage)
- Data farm (distributed datacenter)
To make cloud a reality, there are two dependencies.
To be effective:
- Advanced web browsers
- Fast and dependable networks
To be efficient:
- Multiple, massive datacenters
- Low-touch support paradigm
Cloud computing Basics:
- Cloud Taxonomy
- Principle Characteristics of cloud
- Cloud Delivery Models
- Cloud Deployment Models
- Cloud Architecture
The Cloud comprised the following:
On Demand Usage of compute and storage
Six Principle Characteristics
Six Principle Characteristics:
- On Demand Service
- Ubiquitous Network Access
- Location Independent Resource Pooling
- Rapid Elasticity
Cloud Delivery Models:
- Software-as-a –Service (SaaS)
Applications at scale (End users)
- Platform-as-a-Service (Paas)
Execution Platforms at scale (Developers)
- Infrastructure-as-a-Service (Iaas)
Infrastructure at scale (System Administrators)
As the Cloud evolves, new delivery models have been developed by Cloud Providers. Here are few other delivery models.
- Communication-as-a-Service (Caas)
- Monitoring-as-a-Service (Maas)
- Security-as-a-Service (SECaas)
- Everything-as-a-Service (Eaas)
- Anything-as-a-Service (Xaas)
Cloud Deployment Models:
Public Cloud – Cloud Infrastructure made available to the general public.
Private Cloud – Cloud Infrastructure Operated solely for an organization
Hybrid Cloud – Cloud Infrastructure Composed of two or more clouds that interoperate or federate through technology.
Community Cloud – Cloud Infrastructure Shared by several organizations and supporting a specific community.
Virtual Private Cloud – Cloud Infrastructure that simulate the private cloud experiences in public cloud infrastructure.
Cloud Computing Risks: