Cloud Computing

Altaf Hussain, Graduate Student

St. Francis Xavier University

Altaf Hussain || StFX University1

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Cloud Computing

Cloud Computing

Altaf Hussain, Graduate Student

St. Francis Xavier University

Altaf Hussain || StFX University2

Introduction to Cloud

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“Cloud computing has the potential to create irreversible changes in how computers are used around the world”

Cluster ComputingCloud ComputingGrid Computing

What is Cloud Computing?

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When computing services are provided over the Internet rather then locally on a user’s own machine.

Computation is run on an supporting infrastructure which is independent of the applications themselves.

The infrastructure can take on many forms, but to the end user, the implementation is irrelevant, hence the “cloud” abstraction.

In addition, the platform provides on demand services, that are always on, anywhere, anytime and any place.

Pay for use and as needed, elastic (scale up and down in capacity and functionalities).

The hardware and software services are available to the general public, enterprises, corporations and businesses markets.

Change Of Concept

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What’s new?

Acquisition Model: Based on purchasing of services

Business Model: Based on pay for use

Access Model: Over the Internet to ANY device

Technical Model: Scalable, elastic, dynamic, multi-tenant, & sharable

Developers ServiceProviders

Warfighters

Customers

On DemandCommodityFlexibilitySecurity

Virtualization

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Virtual workspaces: An abstraction of an execution environment Resource quota (e.g. CPU, memory share), Software configuration (e.g. OS, provided services).

Implement on Virtual Machines (VMs): Abstraction of a physical host machine, Hypervisor intercepts and emulates instructions from VMs, and

allows management of VMs, VMWare, Xen, IBM Virtual BOX etc.

Provide infrastructure API: Plug-ins to hardware/support structures Hardware

OS

App App App

Hypervisor

OS OS

Virtualized Stack

Virtual Machines

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VM technology allows multiple virtual machines to run on a single physical machine.

Hardware

Virtual Machine Monitor (VMM) / Hypervisor

Guest OS(Linux)

Guest OS(NetBSD)

Guest OS(Windows)

VM VM VM

AppApp AppAppAppXen

VMWare

UML

Denali

etc.

Advantages of Virtual Machines

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Run operating systems where the physical hardware is unavailable,

Easier to create new machines, backup machines, etc., Software testing using “clean” installs of operating systems

and software, Emulate more machines than are physically available, Timeshare lightly loaded systems on one host, Debug problems (suspend and resume the problem machine), Easy migration of virtual machines (shutdown needed or not). Run legacy systems!

What Cloud Computing Offers?

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Services of Cloud Computing

Software as Service (SaaS)

Platform as Service (PaaS)

Infrastructure as Service (IaaS)

Everything as a Service (XaaS)

Software as a Service (SaaS)

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What is SaaS? Software is provided to end users in an “On-demand” fashion. Reduces upfront costs, i.e. buying multiple licenses “Utility-based” computing

SaaS Delivery Model Increasingly popular with SMEs/ISVs No hardware or software to manage Service delivered through a browser

Software as a Service (SaaS)

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Advantages Pay per use Instant Scalability Security Reliability APIs

Examples SalesForce.com Office365 iCloud Drop box, Skydive (windows live), Amazon S3, Google Docs etc.

Platform as a Service (PaaS)

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What is PaaS? Service Provider provide cloud environment for development

and deployment software. Consumer can avoid preparing and manage complex

environment. Some PaaS offers, the underlying compute and storage

resources scale automatically to match application demand such that the cloud user does not have to allocate resources manually.

With the model user can run web service, database, and development and testing tools.

Platform as a Service (PaaS)

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PaaS Delivery Model Platforms are built upon Infrastructure, which is expensive Estimating demand is not a science! Platform management is not fun!

PaaS Service Storage Service Compute Service Scalability

Platform as a Service (PaaS)

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Advantages Pay per use Instant Scalability Security Reliability APIs

Examples Windows Azure App Febric Azure Storage Services Amazon S3 Google AppEngine

Infrastructure as a Service (IaaS)

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What is IaaS? User can get dynamic infrastructure facility by the provider in

virtualized form. Computing hardware

E.g. Client Storage Space, Processing power needs Virtualization

E.g. VM Ware, VirtualBox Networking

Security, communication speeds, servers Utility Computing

E.g. Charging by hour, gigabyte, process load

PaaS Providers: Microsoft Amazon IBM

Example: Google Docs

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Cloud Application(Google Docs)

Cloud Client(Mozilla Firefox)

Cloud hardware(Apps Server)

Cloud Platform(Apps Engine)

Cloud Services(Word Processing)

BigTable

Cloud storage(BigTable DB)

Types of Cloud (According to Service Availability)

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Private Cloud: Access to these services are provided through a dedicated

Government Intranet/ Organization and is not accessible from the Public Internet.

Public Cloud: The cloud infrastructure is made available to the general

public or a large industry group and is owned by an organization selling cloud services.

Types of Cloud (According to Service Availability)

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Community Cloud: The cloud infrastructure is shared by several organizations

and supports a specific community that has shared concerns (e.g., mission, security requirements, policy, and compliance considerations). It may be managed by the organizations or a third party and may exist on premise or off premise.

Hybrid Cloud: The cloud infrastructure is a composition of two or more

clouds (private, community, or public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting).

Types of Cloud (According to Service Availability)

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Inter Cloud: The Intercloud is an interconnected global "cloud of

clouds“ and an extension of the Internet "network of networks" on which it is based.

Describe as the Data Center of the future.

Content Delivery Network (An application of Cloud): A content delivery network or content distribution network

(CDN) is a large distributed system of servers deployed in multiple data centers in the Internet. The goal of a CDN is to serve content to end users with high availability and high performance.

Role and Consumer classification

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Infrastructure Provider Responsible for creation and maintenance of the hardware infrastructure which

supports cloud computing applications. ISVs are the consumers.

Vendors Responsible for creation and distribution of lower-end platforms for cloud

computing. PaaS provider, IaaS consumer

Developers Responsible for the creation of software to be ran on a cloud computing system.

Often works with provides for integration. SaaS provider and PaaS consumer

Users Responsible for the consumption of cloud-computing services. SaaS consumers

SLA: Service Level Agreement

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A service-level agreement (SLA) is a part of a service contract where the level of service is formally defined.

In practice, the term SLA is sometimes used to refer to the contracted delivery time (of the service) or performance.

As an example, internet service providers will commonly include service level agreements within the terms of their contracts with customers to define the level(s) of service being sold in plain language terms

SLA: Service Level Agreement

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Source: https://www.windowsazure.com/en-us/support/sla/

Quality Of Service (QoS)

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Indicate the degree to service requirement meet by the service providers.

Amazon EC2 cloud service hit by botnet, outage - The cloud-based EC2 (Elastic Compute Cloud) was kept jumping this past week by two incidents: a compromised internal service that triggered a botnet, and a data center power failure in Virginia.

Heroku learns the hard way from Amazon EC2 outage - Ruby on Rails Platform as a Service startup Heroku started off the new year with a nasty surprise. Without warning on January 2, all of the specialized, high-capacity Amazon EC2 instances that run its popular application and development service disappeared in the blink of an eye.

Windows Azure- it was a software bug dealing with the leap year calculation for their compute service. Within 9 hours they had a solution and started to deploy it out across the network.

Application Model

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A development Model on Windows Azure

Application Development

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Risk in Cloud Computing

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Security: Organization dealing with sensitive data are reluctant to use cloud.

Downtime: Any downtime has a major implication with no service consumers

Dependency: Vendor lock-in is a major issue Interoperability: No interoperability among cloud.

Future Research Aspects

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Data Security and Data Management Access Control Automatic Service Level Agreement QoS improvement and Risk mitigation Green Cloud Dynamic Application Provisioning SE methodologies and Practice for Cloud computing Inter Cloud and Open Cloud