Cloud Foundation Concepts

 

Cloud economics

• CAPEX: Capital Expenditure. is the money an organization or corporate entity spends to buy, maintain, or improve its fixed assets, such as buildings, vehicles, equipment, or land.

• OPEX: Operation Expenditure: is the ongoing cost. The labor cost, the power bill, a utility bill, etc

• The Cloud model is so attractive from a business perspective because it lets you trade CAPEX for OPEX. So instead of having to invest heavily in data centers and infrastructure in the cloud, you can pay only when you consume resources

Cloud Computing

• On-demand/Self-service: Provision computing capabilities as needed automatically without requiring human interaction with service providers.

• Network Access: Capabilities available over the network and accessed through standard mechanism ordering to demand.

• Resource Pooling: The provider’s computing resources are pooled to serve multiple consumers using a multi-tenant model, with different resources dynamically assigned and reassigned.

• Rapid Elastic:  Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward with demand.

• Measured service: Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and consumer of the utilized service.

Service Model

• Infrastructure as a Service (IaaS) 
• IaaS provides cloud-based infrastructure services that provide compute, storage, and network capacity. 
• The cloud subscriber is usually responsible for installing, configuring, securing, and maintaining any software on the cloud-based infrastructure

• Platform as a service (PaaS) Providers manage
• Infrastructure
• Operating System
• Middleware
• Runtime
• Subscriber manages the Application and Data

• Software as a service (SaaS). Providers managed
• Platform
• Data 
• Application

Cloud Terminology

• High Availability (HA): Compute environment configured to provide

• Full-time availability

• Has redundant software and hardware that makes the system available despite failures.

• Avoid having a single point of failure.

• Disaster Recovery (DR): involves a set of policies, tools, and procedures to enable the recovery or continuation of vital technology infrastructure and systems.

• Recovery point objective (RPO): measure the transaction loss in time. For example, losing 8 hours worth of business transactions.

• Recovery Time Objective (RTO): Measure the downtime to recover. This measures how much time a business tolerate being down.

• Fault Tolerance: Describes how a cloud vendor ensures minimal downtime for provided services.

• Scalability: There are two kinds of scalability

• Horizontal scaling: 

• Scaling out: Adding more servers

• Scaling in: Reduce the number of servers.

• Vertical scaling

• Scaling up: Increase the power of the server (Bigger shape)

• Scaling down: reduce the power of the server. (smaller shape)

• Elasticity: the ability to quickly increase or decrease resources. Not just limited to virtual machines, it can be your storage, network, etc.