1. Altaf Hussain, Graduate Student St. Francis Xavier University
Cloud Computing
Cloud Computing
Altaf Hussain, Graduate Student
St. Francis Xavier University
Altaf Hussain || StFX University 1

2. Altaf Hussain, Graduate Student St. Francis Xavier University
Cloud Computing
Altaf Hussain, Graduate Student
St. Francis Xavier University
Altaf Hussain || StFX University

3. Introduction to Cloud
“Cloud computing has the potential to create irreversible changes in how computers are used around the world”
Cluster Computing
Cloud Computing
Grid Computing 
Altaf Hussain || StFX University

4. What is Cloud Computing?
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.
Altaf Hussain || StFX University

5. Cloud Computing Vision and Mission
Cloud Computing Vision Statement
Establish secure, easy to use, rapidly provisioned IT services for the Federal Government, including:
Agile and simple acquisition and certification processes;
Elastic, usage-based delivery of pooled computing resources;
Portable, reusable and interoperable business-driven tools;
Browser-based ubiquitous internet access to services; and
Always on and available, utility-like solutions.
Cloud Computing Mission Statement
Drive the government-wide adoption of cost effective, green and sustainable Federal cloud computing solutions.
Altaf Hussain || StFX University

6. Change Of Concept Developers Service Providers Warfighters Customers
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
Service
Providers
Warfighters
Customers
On Demand
Commodity
Flexibility
Security
Altaf Hussain || StFX University

7. Virtualization 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
App
App
App OS OS OS
Hypervisor
Hardware
Virtualized Stack
Altaf Hussain || StFX University

8. Virtual Machine Monitor (VMM) / Hypervisor
Virtual Machines
VM technology allows multiple virtual machines to run on a single physical machine.
App
App
App
App
App VM VM VM
Xen
Guest OS
(Linux)
Guest OS
(NetBSD)
Guest OS
(Windows)
VMWare
UML
Virtual Machine Monitor (VMM) / Hypervisor
Denali
Hardware
etc.
Altaf Hussain || StFX University

9. Advantages of Virtual Machines
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!
Altaf Hussain || StFX University

10. What Cloud Computing Offers?
Services of Cloud Computing
Software as Service (SaaS)
Everything as a Service (XaaS)
Platform as Service (PaaS)
Infrastructure as Service (IaaS)
Altaf Hussain || StFX University

11. Software as a Service (SaaS)
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
Altaf Hussain || StFX University

12. Software as a Service (SaaS)
Advantages
Pay per use
Instant Scalability
Security
Reliability
APIs
Examples
SalesForce.com
Office365
iCloud
Drop box, Skydive (windows live), Amazon S3, Google Docs etc.
Altaf Hussain || StFX University

13. Platform as a Service (PaaS)
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.
Altaf Hussain || StFX University

14. Platform as a Service (PaaS)
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
Altaf Hussain || StFX University

15. Platform as a Service (PaaS)
Advantages
Pay per use
Instant Scalability
Security
Reliability
APIs
Examples
Windows Azure App Febric
Azure Storage Services
Amazon S3
Google AppEngine
Altaf Hussain || StFX University

16. Infrastructure as a Service (IaaS)
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
Altaf Hussain || StFX University

17. Example: Google Docs Cloud Platform (Apps Engine) Cloud Services
(Word Processing)
Cloud hardware
(Apps Server)
Cloud Client
(Mozilla Firefox)
Cloud storage
(BigTable DB)
BigTable
Cloud Application
(Google Docs)
Altaf Hussain || StFX University

18. Types of Cloud (According to Service Availability)
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.
Altaf Hussain || StFX University

19. Types of Cloud (According to Service Availability)
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).
Altaf Hussain || StFX University

20. Types of Cloud (According to Service Availability)
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.
Altaf Hussain || StFX University

21. Role and Consumer classification
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
Altaf Hussain || StFX University

22. SLA: Service Level Agreement
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
Altaf Hussain || StFX University

23. SLA: Service Level Agreement
Source:
Altaf Hussain || StFX University

24. Quality Of Service (QoS)
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.
Altaf Hussain || StFX University

25. Application Model A development Model on Windows Azure
Altaf Hussain || StFX University

26. Application Development
Altaf Hussain || StFX University

27. Risk in Cloud Computing
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.
Altaf Hussain || StFX University

28. Future Research Aspects
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
Altaf Hussain || StFX University