Cloud Computing: An Introduction

Cloud Computing and Virtualization-

Newest TrendsSrinath Perera, Ph.D.

Senior Software Architect, WSO2Research Scientist, Lanka Software Foundation

Member, Apache Software FoundationVisiting Faculty, University of Moratuwa

Next 1 hour: Goal What is Cloud? More on Why and

When and less about How?

Take home is some idea of when to and when not to use the Cloud

Men, it has been well said, think in herds; it will be seen that they go mad in herds, while they only recover their senses slowly, and one by

one. ~ Charles Mackay

Copied from http://www.flickr.com/photos/54555810@N00/2848637190/, by Rambling Traveler

Gold Rush

Very good example of a hype Only few actually made money But associated services (merchants

and transportations) made lot of money

The Cloud Bandwagon Is Cloud a hype? Of course

it is! Is it Just hype? may be not,

thats what we will discuss.

But don’t get me wrong, even if it is a hype, that

doesn’t mean we should not be talking about it.

Image from http://www.flickr.com/photos/88929764@N00/4436978855/

Some Hypes Deliver: Hype Cycle

We have to understand what it is and what drives it? That would tell us how to navigate.

Selling Shovels In the Gold Rush

Hype change the demand and supply dynamics.

Fire Open up the space for new Trees

Hypes often change the dynamics, and give a chance for new comers to climb to the top

Image from http://www.flickr.com/photos/leppre/485528374/

So What is Cloud?

Based on the idea that computation and storage can be rented as a utility from data centers that runs somewhere (in the cloud) on demand.

− Remote resources that are rented− On demand and in elastic manner− Pay as you go

Electricity as a Utility as an Example

Now, no one run generators themselves Use electricity that is remotely generated Can draw when need it Only pay for what you use

Electricity as a Utility: Benefits

Small startup cost (do not have to buy a generator)

No operational cost Do not need to do capacity planning Overall cheaper electricity due to

economics of scale Making it parts of the everyday life,

commodity (accessibility)

Image from http://www.flickr.com/photos/infomofo/3220498521

Benefits of the Cloud Avoid/reduce operational

costs by outsourcing Can scale up and down as

needed Pay as you go Making it parts of the

everyday life, commodity (accessibility)

Cheaper computing power due to economy of scale

Drivers of Cloud

Unused computing power at Google, Amazon Max load >> average load High operational cost, need for outsourcing Availability of large scale solutions and

infrastructure as side efforts of high tech company operations

Cloud Classification

For end-users

For developers, integrators, architects

For infrastructure specialists

IaaS Example: Amazon Two services

− S3 Storage− EC2 computing cloud

Based on Virtualization, where each user is given a virtual machine and charged by the hour

Need least amount of changes to move apps to the Cloud. They in a way replace hosting services

Least amount of out of the box services (e.g. DOS attack prevention) and advanced services like scaling etc., are a responsibility of the user.

Often the best choice for ad-hoc computer users.

PaaS Example: Google App Engine

Support Java and Python Support web requests and run user written web

applications in an isolated environment− Java version based on servlets

Support storage based on Big table, memcache based cache, and auto scaling

Can write apps locally, test it, and then upload to the Cloud

SaaS Example: Salesforce

Provide support for CRM (Customer Relationship Management) software as a Service

The application available out of the box users just configure and use it.

Salesforce handles all the details, and a ideal choice for outsourcing IT functions

However, applications are very specific and customizations are limited.

Virtualization

IaaS uses Virtualization to provide infrastructure as a service

Virtualization can add significant overhead (each instruction become 2 instructions)

− new CPUs have hardware support for virtualization, which make things better

− Still I/O is a challenge

Mimic the hardware layer using software, and provide a “virtual” machine to the next layers

− Used to mimic multiple machines within the same machine

− easier manageability and migration (move machines based on load)

− e.g. Vmware, Xen, KVM

Cloud Platform Tradeoffs

Private Cloud

Idea is optimizing resource sharing, utilizations, and operations

− e.g. testing environments Connection to public Cloud is possible

− Amazon VPC uses VPN, WSO2 Cloud Service Gateway

Image http://www.flickr.com/photos/glasgows/536185797/, Some rights reserved by M Glasgow

Run a Cloud within the organization (mainly due

to security concerns).

e.g. Amazon Virtual Private Cloud (VPC), IBM private cloud, WSO2 Stratos private Cloud

Potential Impact

More Room to Outsource Non Key Functions of a Organization

Organizations outsource their non-competitive areas to reduce costs and focus on their own expertise.

IT departments are a major cost in most organizations

Cloud enables Organizations to outsource some of the IT functions

Small Start Up Cost Small start up cost

− Reducing the gap between visionaries and dreamers

− New organization has better chance for outsourcing operations through the Cloud

− Cloud competition likely to drive down hosting prizes

1 computer for 100days = 100 computers for 1 day

Great tool for occasional computations

− Research labs − Reporting collecting data

for a story− New york Times tiff to pdf

conversion Rise of analytics

− great tool for offline analysis

− Business Intelligence (BI) − Audits

Large Scale Computation and Storage Resources becoming a

Commodity

Computer intensive desktop apps (e.g. Excel, 3D Max)

Normal people, not just organizations

can have access to computing power

and storage

Autoscaling and Cloud Bursting

Max load >> average load Allocate based on the load Running internal machines in an average load

(because cloud is still expensive than hardware ) and scale out to cloud when there is high load

− Mimic the Hybrid car

Dangers and Concerns

Privacy/ Security/ Trust

− Can we trust the outsiders to not look at our data? Well it depends. But concern is normal for any out sourcing

− Can we trust their security measures? Does the isolations are good enough?

− If we are keeping data owned by others, what are the legal implications etc.

With cloud you will run your apps and put your data in an outsider's administrative domain

Latency/ Bandwidth Why does electricity as a Utility was so

successful? One key aspect was almost unlimited speed and capacity

Is that the same for Cloud? − Not really, specially for countries like

Sri Lanka− Most people dismiss this, and does

not even want to discuss− But for some apps (e.g. interactive

apps like games) this can be a issue

Possibilities− support for offline operation − Fedex your data

Performance

It will inevitably slower (3-4 times if unlucky) − Often the overhead comes from I/O− Some hit on CPU power− Expect the bottlenecks to shift

Remember performance ≠ scalability − Cloud likely to let you scale out, but performance

on individual nodes likely to go down

In the Cloud, your software will run on an

another layer of abstractions

Challenges Cloud Middleware

− Long running, large scale, fault Tolerant Computations

− Scalable service and resource scheduling

− Scalable, secure, self-managing, fault-tolerant data storage for long running processors

− Multi-tenancy and Isolation− Delegation across organizations

Cloud Operations− Metering and Billing− Provisioning and Monitoring− Data Confidentiality and auditability − Supporting SLA and QOS

Challenges (Contd.) Programming Model

− Parallel Programming (Map Reduce)

− Better App programming models – Web, Jason, APIs

− Supporting Mobile devices

Overall Recommendations

Cloud Platform Tradeoffs

Look back: Recommendations

How can we benefits from the Cloud? My list of benefits were by no means exhaustive.

− If you are small startup? Doing something part time (writing Apps for App Store), then cloud is for you definitely.

− If you have a small data center, need to efficiently manage that and increase utilization, you should think Private Cloud

© Copyright Kirsty Smith and licensed for reuse under this Creative Commons

License

Look back: Recommendations (Contd.)

If your services have a Max load >> Average load, you should think about crowd bursting

If you do heavy computations once in a while (analytics, audits), then use IaaS there.

If you want to outsource some of your IT functions, think SaaS

Before leap think about 3 major concerns of Cloud? − Security/ Privacy, Latency and Performance

How much sharing and savings I need?− IaaS, PaaS, SaaS

Questions?