What is Cloud Computing?

Why call it “Cloud” Computing?

Cloud Computing Key Properties

Advantages• Shift from CAPEX to OPEX

• Lowers barrier for starting a new business/project• Can be cheaper even in the long run

• Economies of scale• Geography

Advantages

• Instant agility

• Security

• Reliability

Challenges• Performance predictability (QoS)

• Vendor lock-in

Challenges• Security and privacy

• Data transfer bottleneck• Uploading 10 TB over 20 Mbps link takes 45 days!

Cloud-friendly Applications• Existing apps that do not require specialized hardware resources

• Internet scale apps• Large user base• Geographic distribution

• Apps with elastic demands

• Burst computing

Cloud Computing Taxonomy

• Infrastructure/hardware as a Service (IaaS)

• Platform as a Service (PaaS)

• Software/Framework as a Service (SaaS/FaaS)

Infrastructure as a service (IaaS)• Also know as Utility Computing• VM images of different OS flavors• Can run any application natively on chosen OS• User administers VMs

• User in charge of elasticity and failover • Almost like buying your how HW• Billing:

• CPU hour• Gigabyte of storage per month• Network traffic in and out of datacenter

• Examples: • Amazon Elastic Compute Cloud (EC2), Rackspace

Platform as a Service (PaaS)• Application need to conform to provider’s API • VM managed automatically by provider

• Automatic scaling and failover• Billing:

• CPU hour• Gigabyte of storage per month• Network traffic in and out of datacenter

• Examples:• Google App Engine, Microsoft Azure, Heroku

Software/Framework as a Service (SaaS/FaaS)

• SaaS: services and applications available on an on-demand basis.

• FaaS: a configurable SaaS• Billing:

• Application specific• Per hour• Per transaction

• Examples:• Salesforce.com • Google Docs

How do they stack up?

Choosing between IaaS and PaaS• IaaS

• Use third party sw or other programming languages• Have existing code• Care about lock in

• Transfer web app to your own server or a different provider• Want complete control• Are OK with the extra work needed to manage the system

• PaaS• Provider’s API provider all needed functionality• Have no issues with lock-in• Don’t want to or cannot afford to manage the servers

Amazon Web Services

Regions and Availability Zones Region

• Set of Availability Zones located in one geographic area• Currently 8 regions:

• Virginia, California, Oregon, IrelandSingapore, Australia, Tokio, Sao Paulo

Availability Zone• Independent failure domains

• Distinct location• Independent power grid and network connection

• Zones within a region networked with inexpensive low-latency connections• Example: us-east-1a, us-east1b, us-east-1c, us-east-1d

Elastic Compute Cloud (EC2) Introduced in 2006 (beta), 2007 (full production version) Based on Xen virtualization Introduced Infrastructure as a Service (IaaS)

• Rent a server on an hourly basis• Renting one instance for 10,000 hours is just as cheap as

renting 10,000 instances for an hour.

EC2 Instance Definition: an active virtual server Created from an Amazon Machine Image (AMI)

• Like a boot CD. Root image with everything necessary to start an instance:

Large number of images available

Usage Model Single AMI used to create multiple instances

• Customized for application• Typically, all applications are pre-loaded

Instance are ephemeral• Created when needed• Terminated when demand goes away

Instance storage (FS) is ephemeral• Goes away when the instance is terminated

Persistent storage:• Amazon Elastic Block Store (EBS) volume• S3, RDS, SimpleDB, DynamoDB

Instance Types

One EC2 Compute Unit provides the equivalent CPU capacity of a 1.0-1.2 GHz 2007 Opteron or 2007 Xeon processor.

Create a Custom EC2 Instance Select AMI Choose instance type Choose availability zone Set key-pair Set security group ssh into instance

• e.g., ssh –i .ssh/csc309.pem ubuntu@ec2-107-20-227-144.compute-1.amazonaws.com

Customize Create Image

Security Group Network firewall rules for instance By default instance is not accessible Can limit by protocol, port, source IP

Key Pairs SSH credentials to log into instance Install private key (pem file) in .ssh ssh –i <keypair>.pem <user>@<instance> e.g., ssh –i .ssh/ece1779.pem ubuntu@23.21.224.179

ami-cafc53a2 Ubuntu 14 Apache2

• sudo /etc/init.d/apache2 start|stop• /var/www/html #root for all web documents • /var/log/apache2 #apache server logs

PHP• /etc/php5/apache2/php.ini # php configuration file

Other tools• eclipse• twm, fvwm, kde • vnc

• vncpasswd # create .vnc/passwd file• vncserver -geometry 1400x900 :1 # starts a new vncserver on display 1

• mysql-workbench

Recommended ReadingThe Cloud at Your ServiceJothy Rosenberg and Art Mateos

Cloud Computing BibleBarrie Sosinsky

Programming Amazon Web ServicesJames Murty

Programming Google App EngineDan Sanderson