Cloud Computing

2009.12.16Presented by Boyoung Kim

Contents

• A Break in the Clouds: Towards a Cloud DefinitionLuis M. Vaquero, Luis Rodero-Merino, Juan Cac-eres, Maik Lindner

• A Short Introduction to Cloud Plat-formsAn enterprise-oriented view

David Chappell, August 2008

Outline

• Introduction• A Cloud Definition• Clouds and Grids Comparison• What is a Cloud Platform?• Examining Cloud Platforms• Summary

Introduction

• Cloud Computing is a new paradigm for the provision of computing infra-structure– Shifts the location of this infrastructure

to the network

• There are many definitions of Cloud Computing but they focus on certain aspect of technology

It’s so co

nfusing

More comprehensive analysis of all the features of Cloud Comput-ing, to reach a definition that en-compasses them

A Cloud Definition

Cloud Characteristics

• Markus Klems claims that immediate scalabil-ity and resources usage optimization are key el-ements for the Cloud

• Some authors focus on the business model and the reduction in capital expenditure (Jeff Kaplan and Reuven Cohen)

Feature Reference

User Friendliness [11, 6, 24]

Virtualization [11, 6, 24, 5]

Internet Centric [11, 6, 24, 5]

Variety of Resources [11, 24, 22]

Automatic Adaptation [11, 14]

Scalability [11, 6, 24, 22, 15]

Resource Optimization [11, 24, 22]

Pay per Use [11, 14, 6, 24, 5]

Service SLAs [11, 6]

Infrastructure SLAs [11]

Scalability [11, 6, 24, 22, 15]Resource Optimization [11, 24, 22]Pay per Use [11, 14, 6, 24, 22]

Proposed Definition

Clouds are a large pool of easily usable and ac-cessible virtualized resources. These resources can be dynamically reconfigured to adjust to a variable load (scale), allowing also for an opti-mum resource utilization. This pool of re-sources is typically exploited by a pay-per-use model in which guarantees are offered by the Infrastruc-ture Provider by means of customized SLAs.

Clouds and Grids Comparison

Clouds and Grids

• A source of confusion around the Cloud concept is its relation with Grid Computing

• Clouds and Grids share similar vi-sions– Reduce computing costs and increase

flexibility and reliability by using third-party operated hardware

A Grid Definition

• In 2002, Ian Foster “a system that coordinates resources which

are not subject to centralized control, using standard, open, general-purpose protocols and interfaces to deliver nontrivial qualities of service”

• More recent definitions emphasize the abil-ity to combine resources from different or-ganizations for a common goal

Re-source

Re-source

Re-source

Re-source

Re-source

A B

Share

Grid

No Share !!

Cloud

Re-source

Re-source

Re-source

Re-source

Re-source

A B

What is a Cloud Platform?

Applica-tion

• If the creators of every on-premises ap-plication first had to build all of these basics, we’d have many fewer applica-tions today

Storage

Applica-tion

O/S

• Similarly, if every development team that wishes to create a cloud applica-tion must first build its own cloud platform, we won’t see many cloud applications.

• Fortunately, vendors are rising to this challenge !

Cloud Platform

• Cloud Platform lets developers write applications that run in the cloud, or use services provided from the cloud, or both

Three Kinds of Cloud Ser-vices

DevelopersUsers

Browser/

Client

Applica-tion

Users

ExtraFunc-tions

Applica-tion

Applica-tion

Platform

Applica-tion

Cloud

On-premises

Software as a Ser-

vice (SaaS)

Attached Services

Cloud Plat-forms

Software as a service (SaaS)

• A SaaS application runs en-tirely in the cloud

• The on-premises client is typically a browser of some other simple client

• Ex) The online alternatives of typical office applications such as word processors

Users

Browser/Client

Applica-tion

Attached services

• An application can enhance its functions by accessing applica-tion-specific services provided in the cloud

• Ex) Apple’s iTunes

Users

ExtraFunc-tions

Applica-tion

Cloud Platforms (PaaS)

• A cloud platform provides cloud-based services for creating applications

• Rather than building their own custom foundation

• Ex) The developers of a new SaaS application could in-stead build on a cloud plat-form Developers

Applica-tion

Applica-tion

Platform

Examining Cloud Platforms

Applica-tion

Operating System

Foundation

Integration

Identity

Appli-cationAppli-cationApplica-

tion

Infrastructure Services

Application Services

Storage

Local Support

Foundation (PaaS)

• Operating System– Amazon’s EC2 (Elastic Compute Cloud)

provides customer-specific Linux instances running in VMs

• Local Support– Google’s AppEngine provides local sup-

port for running Python Web applications– Force.com is aimed at creating data-ori-

ented business applications

Infrastructure Services (IaaS)

• Storage– Amazon’s S3 (Simple Storage Service) – MS’s SSDS (SQL Server Data Services)– Amazon’s SimpleDB

• Integration– Amazon’s SQS (Simple Queue Service)– BizTalk (a relay service)

• Identity– A set of bytes that describes user

Application Services (SaaS)

• Search–Microsoft’s Live Search

• Mapping– Google Maps

• Other application Services

Summary

• Clouds – easily usable and accessible virtualized resources – resources can be dynamically reconfigured to adjust to a

variable load (scale)– optimum resource utilization– pay-per-use basis

• Cloud Platform lets developers write applications that run in the cloud, or use services provided from the cloud, or both– Foundation (Paas)– Infrastructure Services (IaaS)– Application Services (SaaS)