1. Introduction to Cloud Computing

2. Cloud Computing in a nutshell
Analogy to electricity use
Technologies such as cluster, grid, and now cloud computing, have all aimed at allowing access to large amounts of computing power in a fully virtualized manner, by aggregating resources and offering a single system
view
Utility computing describes a business model for on-demand delivery of computing power; consumers pay providers based on usage.
It denotes a model on which a computing infrastructure is viewed as a “cloud,” from which businesses and individuals access applications from anywhere in the world on demand

3. Cloud Computing in a nutshell
BUYYA
“Cloud is a parallel and distributed computing system consisting of a collection of inter-connected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources based on service-level agreements (SLA) established through negotiation between the service provider and consumers.”
NIST
a pay-per-use model for enabling available, convenient, on-demand network access to a shared pool of configurable computing resources (e.g. networks, servers, storage, applications, services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.”

4. Cloud Computing in a nutshell
While there are countless other definitions, there seems to be common
characteristics between the most notable ones listed above, which a cloud should have: (
(i) pay-per-use (no ongoing commitment, utility prices);
(ii) elastic capacity and the illusion of infinite resources;
(iii) self-service interface
(iv) resources that are abstracted or virtualised.

5. Roots of Cloud Computing

6. Roots of Cloud Computing
(i) Mainframe to cloud (ii) SOA, Web Services, Web 2.0 and Mashups (iii) Grid Computing (iv) Utility Computing (v)Hardware Virtualization (vi)Virtual Appliance and OVF (vii) Autonomic Computing

7. From Mainframe to cloud
currently experiencing a switch in the IT world, from in-house generated computing power into utility-supplied computing resources delivered over the Internet as Web services
Computing delivered as a utility can be defined as “on demand delivery of infrastructure, applications, and business processes in a security-rich, shared, scalability based computer environment over the Internet for a fee”
Advantage to both consumer and providers
Earlier provided timeshared mainframes , declined due to advent of fast and inexpensive microprocessors

8. SOA, Web Services, Web 2.0 and Mashups
Web services can glue together applications running on different messaging product platforms, enabling information from one application to be made available to others, and enabling internal applications to be made available over the Internet.
The purpose of a SOA is to address requirements of loosely coupled,
standards-based, and protocol-independent distributed computing
Services such user authentication, , payroll management, and calendars are examples of building blocks that can be reused and combined in a business solution in case a single, ready-made system does not provide all those features

9. Grid Computing
Grid computing is the collection of computer resources from multiple locations to reach a common goal. The grid can be thought of as a distributed system with non-interactive workloads that involve a large number of files.
A key aspect of the grid vision realization has been building standard Web services-based protocols that allow distributed resources to be “discovered, accessed, allocated, monitored, accounted for, and billed for..
Issues:
QOS, Avaibility of resource with diverse software configuration
Soln: virtualisation

10. Utility Computing
Utility computing is a service provisioning model in which a service provider makes computing resources and infrastructure management available to the customer as needed, and charges them for specific usage rather than a flat rate.
In utility computing environments, users assign a “utility” value to their jobs, where utility is a fixed or time-varying valuation that captures various QoS constraints (deadline, importance, satisfaction).
The service providers then attempt to maximize their own utility, where said utility may directly correlate with their profit.

11. Hardware Virtualisation
Hardware virtualization allows running multiple operating systems and software stacks on a single physical platform
3 basic capabilities related to management of workload: isolation, Consolidation and Migration

12. A number of VMM platforms exist that are the basis of many utility or
cloud computing environments.
VMWare ESXi :
pioneer in virtualisation, bare metal hypervisor,
provides advanced virtualization techniques of processor, memory, and I/O. Especially, through memory ballooning and page sharing, it can overcommit memory,
Xen:
open-source project
It has pioneered the para-virtualization concept, on which the guest operating system, by means of a specialized kernel, can interact with the hypervisor, thus significantly improving performance

13. KVM:
kernel-based virtual machine (KVM) is a Linux virtualization subsystem
Is has been part of the mainline Linux kernel since version , thus being natively supported by several distributions.
In addition, activities such as memory management and scheduling are carried out by existing kernel
KVM leverages hardware-assisted virtualization, which improves performance and allows it to support unmodified guest operating systems

14. Virtual Appliance and OVF(open virtual format)
An application combined with the environment needed to run it (operating system, libraries, compilers, databases, application containers, and so forth) is referred to as a “virtual appliance.”
In a multitude of hypervisors, where each one supports a different VM image format and the formats are incompatible with one another, a great deal of interoperability issues arises.
For instance, Amazon has its Amazon machine image (AMI) format, made popular on the Amazon EC2 public cloud. Other formats are used by Citrix XenServer, several Linux distributions that ship with KVM, Microsoft Hyper-V, and VMware ESX

15. Autonomic Computing
The increasing complexity of computing systems has motivated research on autonomic computing, which seeks to improve systems by decreasing human involvement in their operation
Autonomic, or self-managing, systems rely on monitoring probes and gauges (sensors), on an adaptation engine (autonomic manager) for computing optimizations based on monitoring data, and on effectors to carry out changes on the system.

16. Migration when and how to migrate one’s application into a cloud ?
what part or component of the IT application to migrate into a cloud and what not to migrate into a cloud ?
what kind of customers really benefit from migrating their IT into the cloud ?

17. The Seven-Step Model of Migration into a Cloud

18. The Seven-Step Model of Migration into a Cloud

19. The Seven-Step Model of Migration into a Cloud
Cloud migration assessments comprise assessments to understand the issues involved in the specific case of migration at the application level or the code, the design, the architecture, or usage levels.
These assessments are about the cost of migration as well as about the ROI that can be achieved in the case of production version.
Step 2
isolating all systemic and environmental dependencies of the enterprise application components within the captive data center
Step 3
generating the mapping constructs between what shall possibly remain in the local captive data center and what goes onto the cloud.

20. The Seven-Step Model of Migration into a Cloud
substantial part of the enterprise application needs to be rearchitected, redesigned, and reimplemented on the cloud.
Step 5
We leverage the intrinsic features of the cloud computing service to augment our enterprise application in its own small ways.
Step 6
we validate and test the new form of the enterprise application with an extensive test suite that comprises testing the components of the enterprise application on the cloud as well
Step 7
Test results could be positive or mixed.
In the latter case, we iterate and optimize as appropriate. After several such optimizing iterations, the migration is deemed successful

21. The Seven-Step Model of Migration into a Cloud

22. Abstraction:
Cloud computing abstracts the details of system implementation from users and developers.
Applications run on physical systems that aren't specified,
data is stored in locations that are unknown,
administration of systems is outsourced to others, and access by users is ubiquitous.

23. Virtualization:
Cloud computing virtualizes systems by pooling and sharing resources.
Systems and storage can be provisioned as needed from a centralized infrastructure,
costs are assessed on a metered basis,
multi-tenancy is enabled,
and resources are scalable with agility.

24. Cloud Types Deployment Model: Service Model Some widely used model
Refers to location and management of the cloud’s infrastructure
Service Model
Consists of particular types of services that can be accessed on cloud computing platform
Some widely used model
NIST Model
The Cloud Cube Model

25. National Institute of Standard and Technology (NIST Definition of Cloud Computing)

26. The Cloud Cube Model
Physical location of the data: Internal (I) / External (E) determines your organization's boundaries.
Ownership: Proprietary (P) / Open (O) is a measure of not only the technology ownership, but of interoperability, ease of data transfer, and degree of vendor application lock-in.
Security boundary: Perimeterised (Per) / De-perimiterised (D-p) is a measure of whether the operation is inside or outside the security boundary or network firewall.
Sourcing: Insourced or Outsourced means whether the service is provided by the customer or the service provider.

28. Deployment Models

29. Public Cloud Private Cloud Hybrid Cloud Community Cloud
Hosted , operated and managed by a third party system owned by organization selling cloud services
Private Cloud
The private cloud infrastructure is operated for the exclusive use of an
organization. The cloud may be managed by that organization or a third
party. Private clouds may be either on- or off-premises.
Hybrid Cloud
A hybrid cloud combines multiple clouds (private, community of public) where those clouds retain their unique identities, but are bound together as a unit.
Community Cloud
A community cloud is one where the cloud has been organized to serve a common function or purpose.
It may be for one organization or for several organizations, but they share common concerns such as their mission, policies, security, regulatory compliance needs, and so on

30. Service Models

31. Infrastructure as a Service(IaaS)
Deliver Infrastructure on Demand in the form of virtual Hardware, Storage and Networking. Virtual Hardware is utilised to provide compute on demand in the form of virtual machine instances
Eg.Amazon EC2, S3, Eucalyptus, GoGrid, Rightspace Cloud
Platform as a Service (PaaS)
Deliver scalable and elastic runtime environments on demand that host the execution of applications.
Backed by core middleware platform for creating abstract environment to deploy and execute application
Software as a service (SaaS)
Provide application and services on demand eg office automation, Photo Editing software, facebook., Twitter accessible through browser on demand

32. Cloud Companies/Service Providers

33. Benefits of Cloud Computing
Lower Computational Costs
Improved Performance
Reduced Software Costs
Instant Software updates
Unlimited storage capacity
Increased Data Reliability
Universal Document Access
Latest version availability
Easier Group Collaboration/ Sharing
Device Independence
Lower computer costs:
You do not need a high-powered and high-priced computer to run cloud computing's web-based applications. Since applications run in the cloud, not on the desktop PC, your desktop PC does not need the processing power or hard disk space demanded by traditional desktop software.
Improved performance:
Computers in a cloud computing system boot and run faster because they have fewer programs and processes loaded into memory…
Reduced software costs:
Instead of purchasing expensive software applications, you can get most of what you need for free.
e.g. most cloud computing applications today, such as the Google Docs suite. better than paying for similar commercial software
which alone may be justification for switching to cloud applications.
Instant software updates:
Another advantage to cloud computing is that you are no longer faced with choosing between obsolete software and high upgrade costs.
When the application is web-based, updates happen automatically available the next time you log into the cloud.
When you access a web-based application, you get the latest version without needing to pay for or download an upgrade.
Unlimited storage capacity:
Cloud computing offers virtually limitless storage.
Your computer's current 1 Tbyte hard drive is small compared to the hundreds of Pbytes available in the cloud.
Increased data reliability:
In a world where few individual desktop PC users back up their data on a regular basis, cloud computing is a data-safe computing platform! if your personal computer crashes, all your data is still out there in the cloud, still accessible
Universal document access:
That is not a problem with cloud computing, because you do not take your documents with you.
Instead, they stay in the cloud, and you can access them whenever you have a computer and an Internet connection
Documents are instantly available from wherever you are
Latest version availability:
When you edit a document at home, that edited version is what you see when you access the document at work.
The cloud always hosts the latest version of your document as long as you are connected, you are not in danger of having an outdated version
Easier group collaboration:
Sharing documents leads directly to better collaboration. Many users do this as it is an important advantages of cloud computing. Multiple users can collaborate easily on documents and projects. Example : sharing excel sheet to fill up by every employee using google docs
Device independence.
You are no longer tethered to a single computer or network. Changes to computers, applications and documents follow you through the cloud. Move to a portable device, and your applications and documents are still available.

34. Disadvantages of Cloud Computing
Requires constant Internet Connection
Does not work well with low speed connection
Stored data might not be Secured
Stored data can be lost
Features might be limited
Requires a constant Internet connection:
Cloud computing is impossible if you cannot connect to the Internet
Does not work well with low-speed connections:
Similarly, a low-speed Internet connection, such as that found with dial-up services, makes cloud computing painful at best and often impossible.
Stored data might not be secure:
With cloud computing, all your data is stored on the cloud. The questions is How secure is the cloud?
Can unauthorised users gain access to your confidential data?
Stored data can be lost:
Theoretically, data stored in the cloud is safe, replicated across multiple machines.
But on the off chance that your data goes missing, you have no physical or local backup.
Features might be limited:
This situation is bound to change, but today many web-based applications simply are not as full-featured as their desktop-based applications. For example, you can do a lot more with Microsoft PowerPoint than with Google Presentation's web-based offering

35. Cloud Computing
Cloud computing is particularly valuable because it shifts capital expenditures into operating expenditures.
It also shifts risk away from an organization and onto the cloud provider.
Cloud computing presents new opportunities to users and developers because it is based on the paradigm of a shared multitenant utility.
A cloud is an infrastructure that can be partitioned and provisioned, and resources are pooled and virtualized. If the cloud is available to the public on a pay-as-you-go basis, then the cloud is a public cloud, and the service is described as a utility

36. These are the unique characteristics of an ideal cloud computing model:
• Scalability: You have access to unlimited computer resources as needed.
• Elasticity: You have the ability to right-size resources as required.
• Low barrier to entry: You can gain access to systems for a small investment.
• Utility: A pay-as-you-go model matches resources to need on an ongoing basis. .

37. Companies become cloud computing providers for several reasons: • Profit: The economies of scale can makethis a profitable business. • Optimization: The infrastructure already exists and isn't fully utilized. - Amazon Web Services. • Strategic: A cloud computing platform extends the company's products and defends their franchise. - Microsoft's Windows Azure Platform. • Extension: A branded cloud computing platform can extend customer relationships by offering additional service options. - various IBM cloud services.

38. • Presence: Establish a presence in a market before a large competitor can emerge. - Google App Engine allows a developer to scale an application immediately. For Google, its office applications can be rolled out quickly and to large audiences. • Platform: A cloud computing provider can become a hub master at the center of many ISV's (Independent Software Vendor) offerings. - The customer relationship management provider SalesForce.com has a development platform called Force.com that is a PaaS offering.

39. The law of cloudonomics
1. Utility services cost less even though they cost more.
Utilities charge a premium for their services, but customers save money by not paying for services that they aren't using.
2. On-demand trumps forecasting.
The ability to provision and tear down resources (de-provision) captures revenue and lowers costs.
3. The peak of the sum is never greater than the sum of the peaks.
A cloud can deploy less capacity because the peaks of individual tenants in a shared system are averaged over time by the group of tenants. .

40. The law of cloudonomics
4. Aggregate demand is smoother than individual. Multi-tenancy also tends to average the variability intrinsic in individual demand. With a more predictable demand and less variation, clouds can run at higher utilization rates than captive systems. This allows cloud systems to operate at higher efficiencies and lower costs. 5. Average unit costs are reduced by distributing fixed costs over more units of output. Cloud vendors have a size that allows them to purchase resources at significantly reduced prices. 6. Superiority in numbers is the most important factor in the result of a combat (Clausewitz). Weinman argues that a large cloud's size has the ability to repel botnets and DDoS attacks better than smaller systems do.

41. The law of cloudonomics
7. Space-time is a continuum (Einstein/Minkowski). The ability of a task to be accomplished in the cloud using parallel processing allows real-time business to respond quicker to business conditions and accelerates decision making providing a measurable advantage. 8. Dispersion is the inverse square of latency. Cutting latency in half requires four times the number of nodes in a system. 9. Don't put all your eggs in one basket. Large cloud providers with geographically dispersed sites worldwide therefore achieve reliability rates that are hard for private systems to achieve.

42. The law of cloudonomics
10. An object at rest tends to stay at rest (Newton). Private datacenters tend to be located in places where the company or unit was founded or acquired. Cloud providers can site their datacenters in what are called “greenfield sites.” A greenfield siteis one that is environmentally friendly: locations that are on a network backbone, have cheap access to power and cooling, where land is inexpensive, and the environmental impact is low.

43. Laws of Behavioral Cloudonomics to cloud adoption
1. People are risk averse and loss averse.
2. People have a flat-rate bias.
3. People have the need to control their environment and remain autonomous.
4. People fear change.
5. People value what they own more than what they are given.
6. People favor the status quo and invest accordingly.

44. 7. People discount future risk and favor instant gratification.
8. People favor things that are free.
9. People have the need for status.
10. People are incapacitated by choice.

45. Measuring cloud computing costs
The cost of a cloud computing deployment is roughly estimated to be
CostCLOUD = Σ(UnitCostCLOUD x (Revenue – CostCLOUD))
where the unit cost is usually defined as the cost of a machine instance per hour or another resource.

46. To compare your cost benefit with a private cloud, you will want to compare the value you determine in the previous equation with the same calculation:
CostDATACENTER = Σ(UnitCostDATACENTER x (Revenue –(CostDATACENTER/Utilization))

47. The CostDATACENTER consists of the summation of the cost of each of the individual systems with all the associated resources, as follows:
CostDATACENTER = 1nΣ(UnitCostDATACENTER x (Revenue –
(CostDATACENTER/Utilization))SYSTEMn,
where the sum includes terms for System 1, System 2, System 3, and so on.

48. The costs associated with the cloud model are calculated rather differently. Each resource has its own specific cost and many resources can be provisioned independently of one another. In theory, therefore,
the CostCLOUD is better represented by the equation:
CostCLOUD = 1nΣ(UnitCostCLOUD x (Revenue – CostCLOUD))INSTANCEn +
1nΣ(UnitCostCLOUD x (Revenue – CostCLOUD))STORAGE_UNITn +. 1nΣ(UnitCostCLOUD x
(Revenue – CostCLOUD))NETWORK_UNITn + …

49. Defining Licensing Models
When you purchase shrink-wrapped software, you are using that software based on a licensing agreement called a EULA or End User License Agreement. The EULA may specify that the software meets the following criteria:
• It is yours to own.
• It can be installed on a single or multiple machines.
• It allows for one or more connections.
• It has whatever limit the ISV(independent software vendor) has placed on its software.
In most instances, the purchase price of the software is directly tied to the EULA.

50. The essence of a service oriented design is that services are constructed from a set of modules using standard communications and service interfaces.
An example of a set of widely used standards describes the services themselves in terms of the Web Services Description Language (WSDL), data exchange between services using some form of XML, and the communications between the services using the SOAP protocol.