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Traditional IT Overview

IT Terminology

Network

Cables, routers and servers connected with each other.

Router

A networking device that forwards data packets between computer networks. They know where to send your packets on the internet.

Switch

Takes a packet and send it to the correct server / client on your network.

Problems with traditional IT approach

• Pay for the rent for the data centre

• Pay for power supply, cooling, maintenance

• Adding and replacing hardware takes time

• Scaling is limited

• Hire 24/7 team to monitor the infrastructure

• How to deal with disasters (earthquake, power shutdown, fire, …)

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What is Cloud Computing?

• Cloud computing is the on-demand delivery of compute power, database storage, applications, and other IT resources

• Through a cloud services platform with pay-as-you-go pricing

• You can provision exactly the right type and size of computing resources you need

• You can access as many resources as you need, almost instantly

• Simple way to access servers, storage, databases and a set of application services

• Amazon Web Services owns and maintain the network-connected hardware required for these application services, while you provision and use what you need via a web application

The Deployment Models of the Cloud

The Five Characteristics of Cloud Computing

1. On-demand self service:

   Users can provision resources and use them without human interaction from the service provider

2. Broad network access:

   Resources available over the network, and can be accessed by diverse client platforms

3. Multi-tenancy and resource pooling:

   • Multiple customers can share the same infrastructure and applications with security and privacy

   • Multiple customers are serviced from the same physical resources

4. Rapid elasticity and scalability:

   • Automatically and quickly acquire and dispose resources when needed

   • Quickly and easily scale based on demand

5. Measured service:

   Usage is measured, users pay correctly for what they have used

Six Advantages of Cloud Computing

1. Trade capital expense (CAPEX) for operational expense (OPEX)

   • Pay On-Demand: don’t own hardware

   • Reduced Total Cost of Ownership (TCO) & Operational Expense (OPEX)

2. Benefit from massive economies of scale

   Prices are reduced as AWS is more efficient due to large scale

3. Stop guessing capacity

   Scale based on actual measured usage

4. Increase speed and agility

5. Stop spending money running and maintaining data centres

6. Go global in minutes: leverage the AWS global infrastructure

Problems solved by the Cloud

• Flexibility: change resource types when needed

• Cost-Effectiveness: pay as you go, for what you use

• Scalability: accommodate larger loads by making hardware stronger or adding additional nodes

• Elasticity: ability to scale out and scale-in when needed

• High-availability and fault-tolerance: build across data centres

• Agility: rapidly develop, test and launch software applications

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Types of Cloud Computing

Infrastructure as a Service(IaaS)

• Provide building blocks for cloud IT

• Provides networking, computers, data storage space

• Highest level of flexibility

• Easy parallel with traditional on-premises IT

Ex: Amazon EC2(AWS), GCP, Azure, Rackspace, Digital Ocean, Linode

Platform as a Service(PaaS)

• Removes the need for your organizationo to manage the underlying infrastructure

• Focus on the deployment and management of your applications

Elastic Beanstalk(AWS), Heroku, Google App Engine(GCP), Windows Azure(Microsoft)

Software as a Service(SaaS)

• Completed product that is run and managed by the service provider

On-premises vs Iaas vs Paas vs Saas

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AWS Cloud Overview

AWS Regions

• AWS has Regions all around the world

• Names can be us-east-I, eu-west-3, …

• A region is a cluster of data centers

• Most AWS services are region-scoped

How to choose an AWS Region?

• Compliance with data governance and legal requirements: data never leaves a region without your explicit permission

• Proximity to customers: reduced latency

• Available services within a Region: new services and new features aren’t available in every Region

• Pricing: pricing varies region to region and is transparent in the service pricing page

AWS Availability Zones

• Each region has many availability zones. (usually3, min is 3, max is 6). Example:

  • ap-southeast-2a

  • ap-southeast-2b

  • ap-southeast-2c

• Each availablity zone (AZ) is one or more discrete data centers with redundant power, networking, and connectivity

• They’re separate from each other, so that they’re isolated from disasters

• They’re connected with high bandwidth, ultra-low latency networking

AWS Points of Presence (Edge Locations)

• Amazon has 400+ Points of Presence (400+ Edge Locations & 10+ Regional Caches) in 90+cities across 40+ countries

• Content is delivered to end users with lower latency

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