cloud computing project

Institute of Science and technology

B.Sc(Honors) on Electronics & Communication Engineering

Part:4

Subject Code: 412

Project name: Cloud Computing

Prepared By

Minhaz Mohammad Kowsar

Roll: 108042, Registration: 707067

Supervised By

Mehedi Hasan

Date:April, 2012

C l o u d C o m p u t i n g P a g e | 2

ECE 4th Year Project IST, Dhaka



Acknowledgement



Contents

1. Abstract

2. Introduction

3. The Concept

4. Comparison with other sytems

5. Brief history

6. Service model of Cloud computing

7. Deployment model of cloud computing

8. Architecture of cloud computing

9. Cloud consumption type

10. Obstackels

11. Advantages

12. Example

13. Some issues

14. Research

15. future



Abstract

Imagine yourself in the world where the users of the computer of todays internet

world dont have to run, install or store their application or data on their own

computers, imagine the world where every piece of your information or data

would reside on the Cloud (Internet).

As a metaphor for the Internet, "the cloud" is a familiar clich, but when combined with "computing", the meaning gets bigger and fuzzier. Some analysts and vendors define cloud computing narrowly as an updated version of utility computing: basically virtual servers available over the Internet. Others go very broad, arguing anything you consume outside the firewall is "in the cloud", including conventional outsourcing.

Cloud computing comes into focus only when you think about what we always need: a way to increase capacity or add capabilities on the fly without investing in new infrastructure, training new personnel, or licensing new software. Cloud computing encompasses any subscription-based or pay-per-use service that, in real time over the Internet, extends ICT's existing capabilities.

Cloud computing is at an early stage, with a motley crew of providers large and small delivering a slew of cloud-based services, from full-blown applications to storage services to spam filtering. Yes, utility-style infrastructure providers are part of the mix, but so are SaaS (software as a service) providers such as Salesforce.com. Today, for the most part, IT must plug into cloud-based services individually, but cloud computing aggregators and integrators are already emerging.



Introduction

this project is done about all about cloud computing. this project includes

what is cloud

characteristics

Brief history

types of Cloud Services

its clients

How to deploy Cloud system

the Architecture of cloud sytem

Software and applications regarding Cloud

Some issues like, Privacy, legal, security, open source and Sustainability

researches in this cloud computing

References



Cloud computing- The Concept

Cloud computing is Internet ("cloud") based development and use of computer technology ("computing"). It is a style of computing in which dynamically scalable and often virtualized resources are provided as a service over the Internet. Users need not have knowledge of, expertise in, or control over the technology infrastructure "in the cloud" that supports them.

Cloud computing entrusts, typically centralized, services with your data, software, and computation on a published application programming interface (API) over a network. It has a lot of overlap with software as a service (SaaS).

End users access cloud based applications through a web browser or a light weight desktop or mobile applications while the business software and data are stored on servers at a remote location. Cloud application providers strive to give the same or better service and performance than if the software programs were installed locally on end-user computers.

At the foundation of cloud computing is the broader concept of infrastructure convergence (or Converged Infrastructure) and shared services. This type of data centre environment allows enterprises to get their applications up and running faster, with easier manageability and less maintenance, and enables IT to more rapidly adjust IT resources (such as servers, storage, and networking) to meet fluctuating and unpredictable business demand.



The two words in the phrase Cloud Computing have the following interpretations:

Cloud: As a noun, this is a metaphor for the Internet, and as an adjective it means pertaining to the Internet. This usage derives from the cloud symbols that represent the Internet on diagrams.

Computing: Any IT activity carried out by an entity:

When using "a local server or a personal computer", which implies

that the IT resources are under the exclusive control of the entity.

To "store, manage, and process data, which implies that the data

is private to the entity, in the sense that it is determined by them, even if it

is accessible by others.

This means that Cloud Computing is a type of Internet-based computing, and it consists of every situation where the use of IT resources by an entity has all of the following characteristics:

Access to the resources is:

Controlled by the entity, and restricted by them to their authorized

users.

Delivered via the Internet to all of these users.

The resources are:

Hosted by a service provider on behalf of the entity.

Dedicated to the exclusive use of the entity.

Data processed by the resources is:

Private to the entity and its associates.

Entered or collected by them, or automatically produced for them.

Depending on the context, Cloud Computing can mean:

Access to and use of the resources.

The hosting and delivery service that provides this access.

A model for enabling such access and delivery.

The hosted resources or services themselves.

The computing execution carried out by the services.

Technology used for the provision of the services.



Comparison with other systems

Cloud computing shares characteristics with:

Autonomic computing Computer systems capable of self-management.

Clientserver model Clientserver computing refers broadly to

any distributed application that distinguishes between service providers

(servers) and service requesters (clients).

Grid computing "A form of distributed and parallel computing, whereby

a 'super and virtual computer' is composed of a cluster of networked, loosely

coupled computers acting in concert to perform very large tasks."

Mainframe computer Powerful computers used mainly by large

organizations for critical applications, typically bulk data processing such

as census, industry and consumer statistics, police and secret intelligence

services, enterprise resource planning, and financial transaction processing.

Utility computing The "packaging of computing resources, such as

computation and storage, as a metered service similar to a traditional public

utility, such as electricity."

Peer-to-peer Distributed architecture without the need for central

coordination, with participants being at the same time both suppliers and

consumers of resources (in contrast to the traditional clientserver model).



Cloud computing exhibits the following key characteristics:

Empowerment of end-users of computing resources by putting the provisioning of those resources in their own control, as opposed to the control of a centralized IT service (for example)

Agility improves with users' ability to re-provision technological infrastructure resources.

Application programming interface (API) accessibility to software that enables machines to interact with cloud software in the same way the user interface facilitates interaction between humans and computers. Cloud computing systems typically use REST-based APIs.

Cost is claimed to be reduced and in a public cloud delivery model capital expenditure is converted to operational expenditure. This is purported to lower barriers to entry, as infrastructure is typically provided by a third-party and does not need to be purchased for one-time or infrequent intensive computing tasks. Pricing on a utility computing basis is fine-grained with usage-based options and fewer IT skills are required for implementation (in-house).

Device and location independence enable users to access systems using a web browser regardless of their location or what device they are using (e.g., PC, mobile phone). As infrastructure is off-site (typically provided by a third-party) and accessed via the Internet, users can connect from anywhere.

Virtualization technology allows servers and storage devices to be shared and utilization be increased. Applications can be easily migrated from one physical server to another.

Characteristics



Multi-tenancy enables sharing of resources and costs across a large pool of users thus allowing for:

1. Centralization of infrastructure in locations with lower costs (such as real estate, electricity, etc.)

2. Peak-load capacity increases (users need not engineer for highest possible load-levels)

3. Utilization and efficiency improvements for systems that are often only 1020% utilized.

Reliability is improved if multiple redundant sites are used, which makes well-designed cloud computing suitable for business continuity and disaster recovery.

Scalability and Elasticity via dynamic ("on-demand") provisioning of resources on a fine-grained, self-service basis near real-time, without users having to engineer for peak loads.

Performance is monitored and consistent and loosely coupled architectures are constructed using web services as the system interface.

Security could improve due to centralization of data, increased security-focused resources, etc., but concerns can persist about loss of control over certain sensitive data, and the lack of security for stored kernels.[17] Security is often as good as or better than other traditional systems, in part because providers are able to devote resources to solving security issues that many customers cannot afford.[18] However, the complexity of security is greatly increased when data is distributed over a wider area or greater number of devices and in multi-tenant systems that are being shared by unrelated users. In addition, user access to security audit logs may be difficult or impossible. Private cloud installations are in part motivated by users' desire to retain control over the infrastructure and avoid losing control of information security.



Maintenance of cloud computing applications is easier, because they do not need to be installed on each user's computer and can be accessed from different places.

So as a summary of previous paragraph we can have six Essential characteristics of Cloud Computing below:

1. On demand self services: computer services such as email, applications, network or server service can be provided without requiring human interaction with each service provider. Cloud service providers providing on demand self services include Amazon Web Services (AWS), Microsoft, Google, IBM and Salesforce.com. New York Times and NASDAQ are examples of companies using AWS (NIST). Gartner describes this characteristic as service based.

2. Broad network access: Cloud Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms such as mobile phones, laptops and PDAs.

3. Resource pooling: The providers computing resources are pooled together to serve multiple consumers using multiple-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. The resources include among others storage, processing, memory, network bandwidth, virtual machines and email services. The pooling together of the resource builds economies of scale (Gartner).

4. Rapid elasticity: Cloud services can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be purchased in any quantity at any time.



5. Measured service: Cloud computing resource usage can be measured, controlled, and reported providing transparency for both the provider and consumer of the utilized service. Cloud computing services use a metering capability which enables to control and optimize resource use. This implies that just like air time, electricity or municipality water IT services are charged per usage metrics pay per use. The more you utilize the higher the bill. Just as utility companies sell power to subscribers, and telephone companies sell voice and data services, IT services such as network security management, data center hosting or even departmental billing can now be easily delivered as a contractual service.

6. Multi Tenacity: is the 6th characteristics of cloud computing advocated by the Cloud Security Alliance. It refers to the need for policy-driven enforcement, segmentation, isolation, governance, service levels, and chargeback/billing models for different consumer constituencies. Consumers might utilize a public cloud providers service offerings or actually be from the same organization, such as different business units rather than distinct organizational entities, but would still share infrastructure.



The term "cloud" is used as a metaphor for the Internet, based on the cloud drawing used in the past to represent the telephone network,[19] and later to depict the Internet in computer network diagrams as an abstraction of the underlying infrastructure it represents.

The ubiquitous availability of high capacity networks, low cost computers and storage devices as well as the widespread adoption of virtualization, service-oriented architecture, autonomic, and utility computing have led to a tremendous growth in cloud computing. Details are abstracted from end-users, who no longer have need for expertise in, or control over, the technology infrastructure "in the cloud" that supports them.

The underlying concept of cloud computing dates back to the 1960s, when John McCarthy opined that "computation may someday be organized as a public utility." Almost all the modern-day characteristics of cloud computing (elastic provision, provided as a utility, online, illusion of infinite supply), the comparison to the electricity industry and the use of public, private, government, and community forms, were thoroughly explored in Douglas Parkhill's 1966 book, The Challenge of the Computer Utility. Other scholars have shown that cloud computing's roots go all the way back to the 1950s when scientist Herb Grosch (the author of Grosch's law) postulated that the entire world would operate on dumb terminals powered by about 15 large data centers.

Brief History



The actual term "cloud" borrows from telephony in that telecommunications companies, who until the 1990s offered primarily dedicated point-to-point data circuits, began offering Virtual Private Network (VPN) services with comparable quality of service but at a much lower cost. By switching traffic to balance utilization as they saw fit, they were able to utilize their overall network bandwidth more effectively. The cloud symbol was used to denote the demarcation point between that which was the responsibility of the provider and that which was the responsibility of the user. Cloud computing extends this boundary to cover servers as well as the network infrastructure.

After the dot-com bubble, Amazon played a key role in the development of cloud computing by modernizing their data centers, which, like most computer networks, were using as little as 10% of their capacity at any one time, just to leave room for occasional spikes. Having found that the new cloud architecture resulted in significant internal efficiency improvements whereby small, fast-moving "two-pizza teams" could add new features faster and more easily, Amazon initiated a new product development effort to provide cloud computing to external customers, and launched Amazon Web Service (AWS) on a utility computing basis in 2006.



In early 2008, Eucalyptus became the first open-source, AWS API-compatible platform for deploying private clouds. In early 2008, OpenNebula, enhanced in the RESERVOIR European Commission-funded project, became the first open-source software for deploying private and hybrid clouds, and for the federation of clouds. In the same year, efforts were focused on providing QoS guarantees (as required by real-time interactive applications) to cloud-based infrastructures, in the framework of the IRMOS European Commission-funded project, resulting to a real-time cloud environment. By mid-2008, Gartner saw an opportunity for cloud computing "to shape the relationship among consumers of IT services, those who use IT services and those who sell them" and observed that " organizations are switching from company-owned hardware and software assets to per-use service-based models" so that the "projected shift to cloud computing... will result in dramatic growth in IT products in some areas and significant reductions in other areas.



Infrastructure as a Service (IaaS)

In this most basic cloud service model, cloud providers offer computers as physical or more often as virtual machines , raw (block) storage, firewalls, load balancers, and networks. IaaS providers supply these resources on demand from their large pools installed in data centers. Local area networks including IP addresses are part of the offer. For the wide area connectivity, the Internet can be used or - in carrier clouds - dedicated virtual private networks can be configured.

To deploy their applications, cloud users then install operating system images on the machines as well as their application software. In this model, it is the cloud user who is responsible for patching and maintaining the operating systems and application software. Cloud providers typically bill IaaS services on a utility computing basis, that is, cost will reflect the amount of resources allocated and consumed.

Service Model of Cloud Computing



Some More Detail:

The System Administrators are the subscriber of this service. Usage fees are calculated per CPU hour, data GB stored per hour, network bandwidth consumed, network infrastructure used per hour, value added services used, e.g., monitoring, auto-scaling etc.

The following figure shows IaaS Component Stack and Scope of Control as defined by NIST:

Who are IaaS Subscribers?

The most popular Facebook games created by Zynga.com. It has more than 230 million monthly users run more than 12000 servers on Amazon AWS. When they launch a new game, they start with a few servers and then ramp up their capacity in real time.

To prevent the DDOS attack on its servers, the controversial Wikileaks was hosted on Amazon AWS. Now it seems it has moved back to a Swedish host.

Most important among the lot are SaaS and PaaS Players who are hosted with IaaS providers.

When/Why should opt for an IaaS?

Very useful for startup companies who dont know how successful their newly launched application/website will be.

You have the choice of multiple Operating System, Platforms, Databases and Content Delivery Network (CDN) all in one place.



Platform as a Service (PaaS)

In the PaaS model, cloud providers deliver a computing platform and/or solution stack typically including operating system, programming language execution environment, database, and web server. Application developers can develop and run their software solutions on a cloud platform without the cost and complexity of buying and managing the underlying hardware and software layers. With 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.

Some More Detail:

In plain English, PaaS is a platform where software can be developed,

tested and deployed, meaning the entire life cycle of software can be

operated on a PaaS. This service model is dedicated to application

developers, testers, deployers and administrators. This service provides

everything you need to develop a cloud SaaS application.

The following figure shows PaaS Component Stack and Scope of Control as

defined by NIST:

A PaaS typically includes the development environment,

programming languages, compilers, testing tools and deployment

mechanism. In some cases, like Google Apps Engine (GAE), the

developers may download development environment and use them



locally in the developers infrastructure, or the developer may access

tools in the providers infrastructure through a browser.

Who are PaaS Subscribers?

ISV (Independent Software Vendors), IT Service providers or even I

ndividual developers who want to develop SaaS.

When/Why should you opt for a PaaS?

You focus only on developing the application, everything else will be

taken care of by the platform.

Software as a Service (SaaS)

In this model, cloud providers install and operate application software in the cloud and cloud users access the software from cloud clients. The cloud users do not manage the cloud infrastructure and platform on which the application is running. This eliminates the need to install and run the application on the cloud user's own computers simplifying maintenance and support. What makes a cloud application different from other applications is its elasticity. This can be achieved by cloning tasks onto multiple virtual machines at run-time to meet the changing work demand. Load balancers distribute the work over the set of virtual machines. This process is transparent to the cloud user who sees only a single access point. To accommodate a large number of cloud users, cloud applications can be multitenant, that is, any machine serves more than one cloud user organization. It is common to refer to special types of cloud based application software with a similar naming convention: desktop as a service, business process as a service, Test Environment as a Service, communication as a service.

The pricing model for SaaS applications is typically a monthly or yearly flat fee per user.



Some More Detail:

Here the consumer is free of any worries and hassles related to the service.

The Service Provider has very high administrative control on the application

and is responsible for update, deployment, maintenance and security. The

provider exercises final authority over the application. For example, Gmail

is a SaaS where Google is the provider and we are consumers. We have

very limited administrative and user level control over it, although there is a

limited range of actions, such as enabling priority inbox, signatures, undo

send mail, etc, that the consumer can initiate through settings.

The following figure illustrates the relative levels of control between the

provider and the subscriber SaaS Component Stack and Scope of Control -

borrowed from the NIST document.

Who are SaaS Subscribers?

Apart from organizations and enterprises, SaaS subscribers/users can also

be individuals like you and me. In most of the cases the usage fee is

calculated based on the number of users. For example, Google Apps is free

up to 10 email accounts, but it charges $5 per user per month for Google

Apps for Business(more than 10 users)

When/Why should you opt for a SaaS?

When you want to focus on your business rather than wasting your time in

replacing broken pieces of hardware, managing IT infrastructure, and the

most critical of them all - hiring and retaining your IT staff etc.



Service Model of Cloud Computing in graphical

way



There are several cloud-computing deployment models, and these represent different types of exclusive and non-exclusive clouds provided to consumers or groups of consumers.

Deployment Model of Cloud computing



Public cloud

Public clouds are

cloud systems that are

made available to any

entity in a non-

exclusive group, such

as the general public,

or all organisations in a

specific industry.

Because there are

many consumers,

these are multi-

tenanted clouds. They

are owned by cloud

providers, and are off-premise for all consumers.

The cloud is public only in the sense that, potentially, any entity that requires the

provided services can become a consumer, and a public cloud may not

necessarily be of interest to every entity. For example, a SaaS public cloud might

provide an accounting system that is of interest only to certain types of small

business.

The most ubiquitous, and almost a synonym for, cloud computing. The cloud infrastructure is made available to the general public or a large industry group and is owned by an organization selling cloud services.

Examples of Public Cloud:

Google App Engine Microsoft Windows Azure IBM Smart Cloud Amazon EC2

The main benefits of using a public cloud service are: a. Easy and inexpensive set-up because hardware, application and

bandwidth costs are covered by the provider.



b. Scalability to meet needs. c. No wasted resources because you pay for what you use.

Community cloud

Community cloud shares infrastructure between several organizations from a specific community with common concerns (security, compliance, jurisdiction, etc.), whether managed internally or by a third-party and hosted internally or externally. The costs are spread over fewer users than a public cloud (but more than a private cloud), so only some of the cost savings potential of cloud computing are

realized.

Community

clouds are

supplied to a

group of related

entities that share

a common

purpose, such as mission, security requirements, policy or compliance

considerations, and that therefore need the same type of hosting. These

are multi-tenanted clouds that may be managed by the community or by a

third party, and they may be off-premise for all the consumers, or on-

premise for one of the consumers.

Unlike a private cloud, the community of consumers isn't narrowly

exclusive. However, they may not be truly public clouds, because not every

entity that could use the service may be able to become a consumer.



A Community cloud is for a specific community of consumers from groups or organizations with shared goals or concerns. Any organization or third party can also own this type of cloud.

Hybrid Cloud

A hybrid cloud is a composition of two or more public, private and community

clouds that are used on a day-to-day basis or for cloud bursting.

Becoming part of such a cloud can be attractive to the providers, because it results

in a larger pool of resources that

can be made available to their

consumers, so that variations

in demand can be managed

more flexibly. Also, for

consumers, it may be that

some of their data must be in a

private cloud, for security and

privacy reasons, but it may be

more economical to keep some

other, perhaps less sensitive,

data in a public cloud, because

the cost of these is generally

lower.

A hybrid cloud is also a cloud

of clouds, but the difference

with the latter is that it can contain only one type of cloud deployment, rather than

a mixture of public and private clouds, as with a hybrid.

A hybrid cloud is the intermixing of private and public cloud infrastructures, with private clouds typically confined to an enterprises data centers and public clouds being offered by service providers.



As a combination of these two models, a hybrid cloud enables IT organizations that have already built a private cloud to use resources from public clouds as a way to expand the capabilities of their own IT infrastructure. The critical part of the hybrid model is having a robust, secure, and high-performance network between the private and public cloud so that you can effectively move applications and storage back and forth.

Benefits of Hybrid Cloud a. it allows you to leverage your own assets as well as assets from public

cloud providers to create a more cost-effective and flexible IT environment.

b. It gives you a way to augment your existing facilities, either in terms of handling bursts of traffic or having specific workloads get hosted. You can do that in a very agile manner by using resources from the public cloud. Or you can utilize those external resources to build out your own data center.

Private cloud

Private clouds(also called internal cloud or corporate cloud) are cloud systems

that are accessible only by a single entity, or by an exclusive group of related

entities that share the same purpose and requirements, such as all the

business units in a single organisation. They are generally single-tenanted, but

they can be multi-tenanted if the individual group members act as separate

consumers. They may be owned by a cloud provider and be located off-

premise, or they may be owned and operated by the consumer and be

located on-premise. In the latter case, they can also be known as internal

clouds or corporate clouds. These clouds are usually private because of the



need for system and data security, and, for this reason, they will usually be

behind a firewall that restricts access to a limited set of client devices.

There are some it systems that have some of the same characteristics and

advantages as cloud computing, but that are accessible only through a

private LAN or WAN, rather than the Internet. These have been described as

cloud computing-like, but, because of the shared features, they are

sometimes included as part of cloud computing itself.

Sometimes, Private cloud is a marketing term for a proprietary computing

architecture that provides hosted services to a limited number of people

behind a firewall. Advances in virtualization and distributed computing have

allowed corporate network and datacenter administrators to effectively



become service providers that meet the needs of their "customers" within the

corporation. Marketing media that uses the words "private cloud" is designed

to appeal to an organization that needs or wants more control over their data

than they can get by using a third-party hosted service such as Amazon's

Elastic Compute Cloud (EC2) or Simple Storage Service (S3).

Some other types of cloud deployment models:

Virtual private cloud

When a service provider uses a public-cloud system to create a private cloud, the result is known as a virtual private cloud. Vertical cloud

A vertical cloud is a public cloud optimized for a specific, vertical industry.

A Graphical Summary of Cloud deployment Model



The Architectute of cloud system

Cloud architecture, the systems architecture of the software systems involved in

the delivery of cloud computing, typically involves multiple cloud components

communicating with each other over a loose coupling mechanism such as a

messaging queue. Elastic provision implies intelligence in the use of tight or loose

coupling as applied to mechanisms such as these and others.

The Intercloud

The Intercloud is an interconnected global "cloud of clouds" and an extension of the In the Intercloud is an interconnected global "cloud of clouds" and an extension of the Internet "network of networks" on which it is based. The term was first used in the context of cloud computing in 2007 when Kevin Kelly opined that "eventually we'll have the Intercloud, the cloud of clouds". It became popular in 2009 and has also been used to describe the datacenter of the future. The Intercloud scenario is based on the key concept that each single cloud does not have infinite physical resources. If a cloud saturates, the computational and storage resources of its infrastructure, it would not be able to satisfy further requests for service allocations sent from its clients. The Intercloud scenario aims to address such a situation, and in theory, each cloud can use the computational and storage resources of the infrastructures of other clouds. Such forms of pay-



for-use may introduce new business opportunities among cloud providers if they manage to go beyond the theoretical framework. Nevertheless, the Intercloud raises many more challenges than solutions concerning federation, security, interoperability, vendors' lock-ins, trust, legal issues, QoS, monitoring, and billing. Ternet "network of networks" on which it is based. The term was first used in the context of cloud computing in 2007 when Kevin Kelly opined that "eventually we'll have the Intercloud, the cloud of clouds". It became popular in 2009 and has also been used to describe the datacenter of the future. The Intercloud scenario is based on the key concept that each single cloud does not have infinite physical resources. If a cloud saturates, the computational and storage resources of its infrastructure, it would not be able to satisfy further requests for service allocations sent from its clients. The Intercloud scenario aims to address such a situation, and in theory, each cloud can use the computational and storage resources of the infrastructures of other clouds. Such forms of pay- for-use may introduce new business opportunities among cloud providers if they manage to go beyond the theoretical framework.



Nevertheless, the Intercloud raises many more challenges than solutions concerning federation, security, interoperability, vendors' lock-ins, trust, legal issues, QoS, monitoring, and billing.

Cloud engineering Cloud engineering is the application of engineering disciplines to cloud computing. It brings a systematic approach to the high level concerns of commercialization, standardization, and governance of cloud computing applications. At a practical level it adopts the tools of engineering in conceiving, developing, operating and maintaining cloud computing systems.

Cloud Architecture



Cloud Consumtion Types

The notion of cloud engineering in the context of cloud computing had been sparsely used in discussions, presentations and talks in various occasions in the middle of the 2000s. The term of cloud engineering was formally coined around 2007 and the concept of cloud engineering was officially introduced in April 2009. Various aspects and topics of this subject have been extensively covered in a number of industry events. Extensive research has been conducted on specific areas in cloud engineering, such as development support for cloud patterns, and cloud business continuity services.

Cloud engineering is a field of engineering that focuses on cloud services, such as "software as a service", "platform as a service", and "infrastructure as a service". It is a multidisciplinary method encompassing contributions from diverse areas such as systems engineering, software engineering, web engineering, performance engineering, information engineering, security engineering, platform engineering, service engineering, risk engineering, and quality engineering. The nature of commodity-like capabilities delivered by cloud services and the inherent challenges in this business model drive the need for cloud engineering as the process of "designing the systems necessary to leverage the power and economics of cloud resources to solve business problems."

There are several features of cloud computing that affect consumers in terms of



their day-to-day use of the services, or the way they contract for the services, or

their reasons for choosing one service over another, and these have been called

the consumption model.

Some of them have been described as essential, but it has also been observed

that no single feature is proposed by all definitions and they have been

discussed using terms such as alternatives, options, generally, recurrent ideas or

typically, to indicate that they dont necessarily apply to all cloud services.

We will describe five common types of consumption model of cloud computing system:

Payment and pricing a. Free services

There are cloud services that are entirely free, and some that are offered

on a freemium basis.

b. Commercial services

Where payment is made, typically it is on the basis of consumption in a

given time period, such as per concurrent user per month for SaaS, or

per unit of storage per month for IaaS. Charging by usage can be by any of the following methods:

i. Utility: Consumers pay only for what they use - so called because

it is similar to the pricing of services from electricity utilities.

ii. Subscription: Consumers pay for a fixed amount of resource

whether they use it or not, which is similar to some contracts for

cable TV or mobile telecommunications.

iii. A combination of these, where consumers pay a subscription to

consume up to a certain amount, and then as a utility for

resources consumed above that amount.

c. Ownership

In some cases, cloud systems can be wholly owned by the consumer.



Measured service

Payment on the basis of consumption requires a measured service and a metering capability, but even free services may need to be metered if they apply only up to some level of resource.

Resource pooling

Multi-tenant hosting involves pooled resources that are shared among the several tenants. This can be a consumer advantage, because sharing the resources may lead to lower costs for each tenant. However, resource pooling doesn't apply to a private cloud with only one tenant, because this type of resource sharing applies only between different tenants, rather than among a tenant's individual users. Sharing resources among users applies to any server or datacenter, whether it is part of cloud computing or not.

Scaling and provisioning

Scaling means reconfiguring resources to change their size. Scaling in means to release resources, and scaling out means to acquire more resources. Systems that can easily scale in or out are said to be elastic. Provisioning refers to the mechanisms used to provide and release resources, and hence to manage scaling. Agile provisioning allows the size of resources to be changed very easily, for example without the lengthy decision-making and budgetary process required when purchasing IT equipment for delivery on-premise. Elastic resources and agile provisioning are important for flexible and cost-effective management of variations in user demand. The following terms are used to describe the various scaling and provisioning features that are available with some cloud services: On- demand self service: Scaling that can be performed by the consumer, rather than by the host.

i. Dynamic scaling: Scaling that can be done via software, so

that it can happen automatically and possibly in a way that is

invisible to the consumer.



ii. Infinite scaling: There is no effective limit to the amount of

resource that the consumer can have, although it is always actually

finite at any one time.

iii. Rapid provisioning: Provisioning that can be immediate,

rather than waiting for the cloud provider to respond to a request

for resources.

There is some disagreement as to whether agile provisioning is a defining characteristic of cloud computing.This is partly because the history of IT shows that flexible scaling and provisioning was available prior to the cloud era, and so it is more a feature of IT in general, rather than just cloud systems in particular. However, because large public clouds can have very many tenants, their datacentres can be much more massive than previously known, and so they can give the appearance of unlimited scalability.

Access

a. Broad

Access to cloud services is via the Internet, and this leads to the possibility of consumers having broad access, which means the ability to use the services from multiple types of cloud client, including desktop, portable and hand-held devices, or from many different locations. To achieve access from many different clients, it is necessary for the websites to be made compatible with hand-held devices as well as PCs, for example because of the different screen sizes and the different mechanics of scrolling within large web pages. Access can be from any location where an Internet connection is available, either from a fixed PC, for example in an office or Internet caf, or from anywhere that mobile telephone access is available, for example using a USB modem attached to a notebook. However, a private cloud may only allow access from certain sources, for example if it is behind a firewall.

b. Transparent

In IT, something is transparent to users if they do not need to understand or be aware of it. For example, with cloud computing, consumers can



have transparent access, which means that the users of a service need not be aware of who provides the service or where the host is located. However, for legal and regulatory requirements regarding the security of data and the laws that might apply to breaches of service levels, a consumer may need to have their hosting provided by a known organization in a specific location.



Top 9 Obstacles for Cloud Computing

Availability of a Service

Organizations worry about whether Utility Computing services will have

adequate availability, and this makes some wary of Cloud Computing.

Ironically, existing SaaS products have set a high standard in this regard.

Google Search is effectively the dial tone of the Internet: if people went to

Google for search and it wasnt available, they would think the Internet was

down. Users expect similar availability from new services, which is hard to

do. Table 7 shows recorded outages for Amazon Simple Storage Service

(S3), AppEngine and Gmail in 2008, and explanations for the outages. Note

that despite the negative publicity due to these outages, few enterprise IT

infrastructures are as good.



Just as large Internet service providers use multiple network providers so

that failure by a single company will not take them off the air, we believe

the only plausible solution to very high availability is multiple Cloud

Computing providers. The high-availability computing community has long

followed the mantra no single source of failure, yet the management of a

Cloud Computing service by a single company is in fact a single point of

failure. Even if the company has multiple datacenters in different

geographic regions using different network providers, it may have common

software infrastructure and accounting systems, or the company may even

go out of business. Large customers will be reluctant to migrate to Cloud

Computing without a business-continuity strategy for such situations.

We believe the best chance for independent software stacks is for them to

be provided by different companies, as it has been difcult for one

company to justify creating and maintain two stacks in the name of

software dependability.

Another availability obstacle is Distributed Denial of Service (DDoS) attacks.

Criminals threaten to cut off the incomes of SaaS providers by making their

service unavailable, extorting $10,000 to $50,000 payments to prevent the

launch of a DDoS attack. Such attacks typically use large botnets that rent

bots on the black market for $0.03 per 14bot (simulated bogus user) per

week [36]. Utility Computing offers SaaS providers the opportunity to

defend against DDoS attacks by using quick scale-up. Suppose an EC2

instance can handle 500 bots, and an attack is launched that generates an

extra 1 GB/second of bogus network bandwidth and 500,000 bots. At $0.03

per bot, such an attack would cost the attacker $15,000 invested up front.

At AWSs current prices, the attack would cost the victim an extra $360 per

hour in network bandwidth and an extra $100 per hour (1,000 instances) of

computation. The attack would therefore have to last 32 hours in order to

cost the potential victim more than it would the blackmailer. A botnet

attack this long may be difficult to sustain, since the longer an attack lasts

the easier it is to uncover and defend against, and

the attacking bots could not be immediately re-used for other attacks on

the same provider. As with elasticity, Cloud Computing shifts the attack



target from the SaaS provider to the Utility Computing provider, who can

more readily absorb it and (as we argued in Section 3) is also likely to have

already DDoS protection as a core competency.

Data Lock-In

Software stacks have improved interoperability among platforms, but the

APIs for Cloud Computing itself are still essentially proprietary, or at least

have not been the subject of active standardization. Thus, customers

cannot easily extract their data and programs from one site to run on

another. Concern about the difcult of extracting data from the cloud is

preventing some organizations from adopting Cloud Computing. Customer

lock-in may be attractive to Cloud Computing providers, but Cloud

Computing users are vulnerable to price increases (as Stallman warned), to

reliability problems, or even to providers going out of business.

For example, an online storage service called The Linkup shut down on

August 8, 2008 after losing access as much as 45% of customer data [12].

The Linkup, in turn, had relied on the online storage service Nirvanix to

store customer data, and now there is nger pointing between the two

organizations as to why customer data was lost. Meanwhile, The Linkups

20,000 users were told the service was no longer available and were urged

to try out another storage site.

The obvious solution is to standardize the APIs so that a SaaS developer

could deploy services and data across multiple Cloud Computing providers

so that the failure of a single company would not take all copies of

customer data with it. The obvious fear is that this would lead to a race-to-

the-bottom of cloud pricing and atten the prots of Cloud Computing

providers. We offer two arguments to allay this fear.

First, the quality of a service matters as well as the price, so customers will

not necessarily jump to the lowest cost service. Some Internet Service

Providers today cost a factor of ten more than others because they are

more dependable and offer extra services to improve usability.



Second, in addition to mitigating data lock-in concerns, standardization of

APIs enables a new usage model in which the same software infrastructure

can be used in a Private Cloud and in a Public Cloud.

Such an option could enable Surge Computing, in which the public Cloud

is used to capture the extra tasks that cannot be easily run in the

datacenter (or private cloud) due to temporarily heavy workloads.

Data Condentiality and Auditability

My sensitive corporate data will never be in the cloud. Anecdotally we

have heard this repeated multiple times. Current cloud offerings are

essentially public (rather than private) networks, exposing the system to

more attacks. There are also requirements for audit ability, in the sense of

Sarbanes-Oxley and Health and Human Services Health

Insurance Portability and Accountability Act (HIPAA) regulations that must

be provided for corporate data to be moved to the cloud. We believe that there are no fundamental obstacles to making a cloud-

computing environment as secure as the vast majority of in-house IT environments, and that many of the obstacles can be overcome

immediately with well understood technologies such as encrypted storage,

Virtual Local Area Networks, and network middle boxes (e.g. rewalls, packet lters). For example, encrypting data before placing it in a Cloud

may be even more secure than unencrypted data in a local data center; this approach was successfully used by TC3, a healthcare company with

access to sensitive patient records and healthcare claims, when moving their HIPAA-compliant application to AWS.

Similarly, audit ability could be added as an additional layer beyond the

reach of the virtualized guest OS (or virtualized application environment), providing facilities arguably more secure than those built into the applications themselves and centralizing the software responsibilities related to condentiality and auditability into a single logical layer. Such a new feature reinforces the Cloud Computing perspective of changing our

focus from specic hardware to the virtualized capabilities being provided.



A related concern is that many nations have laws requiring SaaS providers

to keep customer data and copyrighted material within national boundaries. Similarly, some businesses may not like the ability of a country

to get access to their data via the court system; for example, a European customer might be concerned about using SaaS in the United States given the USA PATRIOT Act.

Cloud Computing gives SaaS providers and SaaS users greater freedom to

place their storage. For example,Amazon provides S3 services located

physically in the United States and in Europe, allowing providers to keep

data in whichever they choose. With AWS regions, a simple conguration change avoids the need to nd and negotiate with a hosting provider overseas.

Data Transfer Bottlenecks

Applications continue to become more data-intensive. If we assume

applications may be pulled apart across the

boundaries of clouds, this may complicate data placement and transport.

At $100 to $150 per terabyte transferred,

these costs can quickly add up, making data transfer costs an important

issue. Cloud users and cloud providers have to

think about the implications of placement and trafc at every level of the

system if they want to minimize costs. This

kind of reasoning can be seen in Amazons development of their new

Cloudfront service.

One opportunity to overcome the high cost of Internet transfers is to ship

disks. Jim Gray found that the cheapest

way to send a lot of data is to physically send disks or even whole

computers via overnight delivery services [22].

Although there are no guarantees from the manufacturers of disks or

computers that you can reliably ship data that

way, he experienced only one failure in about 400 attempts (and even this

could be mitigated by shipping extra disks



with redundant data in a RAID-like manner).

A second opportunity is to nd other reasons to make it attractive to keep

data in the cloud, for once data is in the

cloud for any reason it may no longer be a bottleneck and may enable new

services that could drive the purchase of

Cloud Computing cycles. Amazon recently began hosting large public

datasets (e.g. US Census data) for free on S3;

since there is no charge to transfer data between S3 and EC2, these

datasets might attract EC2 cycles. As another

example, consider off-site archival and backup services. Since companies

like Amazon, Google, and Microsoft likely

send much more data than they receive, the cost of ingress bandwidth

could be much less. Therefore, for example, if

weekly full backups are moved by shipping physical disks and compressed

daily incremental backups are sent over

the network, Cloud Computing might be able to offer an affordable off-

premise backup service. Once archived data is

in the cloud, new services become possible that could result in selling more

Cloud Computing cycles, such as creating

searchable indices of all your archival data or performing image recognition

on all your archived photos to group them

according to who appears in each photo. A third, more radical opportunity is to try to reduce the cost of WAN

bandwidth more quickly. One estimate is

that two-thirds of the cost of WAN bandwidth is the cost of the high-end

routers, whereas only one-third is the ber

cost [27]. Researchers are exploring simpler routers built from commodity

components with centralized control as a

low-cost alternative to the high-end distributed routers [33]. If such

technology were deployed by WAN providers, we

could see WAN costs dropping more quickly than they have historically.

Performance Unpredictability



Our experience is that multiple Virtual Machines can share CPUs and main

memory surprisingly well in Cloud Computing, but that I/O sharing is more

problematic. Figure 3(a) shows the average memory bandwidth for 75 EC2

instances running the STREAM memory benchmark [32]. The mean

bandwidth is 1355 MBytes per second, with a

standard deviation of just 52 MBytes/sec, less than 4% of the mean. Figure

3(b) shows the average disk bandwidth

for 75 EC2 instances each writing 1 GB les to local disk. The mean disk

write bandwidth is nearly 55 MBytes per

second with a standard deviation of a little over 9 MBytes/sec, more than

16% of the mean. This demonstrates the problem of I/O interference between virtual machines.

One opportunity is to improve architectures and operating systems to

efciently virtualize interrupts and I/O channels. Technologies such as

PCIexpress are difcult to virtualize, but they are critical to the cloud. One

reason to be

hopeful is that IBM mainframes and operating systems largely overcame

these problems in the 1980s, so we have successful examples from which to learn.

Another possibility is that ash memory will decrease I/O interference.

Flash is semiconductor memory that

preserves information when powered off like mechanical hard disks, but

since it has no moving parts, it is much faster

to access (microseconds vs. milliseconds) and uses less energy. Flash

memory can sustain many more I/Os per second

per gigabyte of storage than disks, so multiple virtual machines with

conicting random I/O workloads could coexist

better on the same physical computer without the interference we see with

mechanical disks. The lack of interference

that we see with semiconductor main memory in Figure 3(a) might extend to semiconductor storage as well, thereby



increasing the number of applications that can run well on VMs and thus

share a single computer. This advance could

lower costs to Cloud Computing providers, and eventually to Cloud

Computing consumers.

Another unpredictability obstacle concerns the scheduling of virtual

machines for some classes of batch processing

programs, specically for high performance computing. Given that high-

performance computing is used to justify

Government purchases of $100M supercomputer centers with 10,000 to

1,000,000 processors, there certainly are many tasks with parallelism that can benet from elastic computing. Cost

associativity means that there is no cost

penalty for using 20 times as much computing for 1=20th the time. Potential applications that could benet include

those with very high potential nancial returnsnancial analysis,

petroleum exploration, movie animationand

could easily justify paying a modest premium for a 20x speedup. One estimate is that a third of todays server market

is high-performance computing [10].

The obstacle to attracting HPC is not the use of clusters; most parallel

computing today is done in large clusters

using the message-passing interface MPI. The problem is that many HPC

applications need to ensure that all the

threads of a program are running simultaneously, and todays virtual

machines and operating systems do not provide a programmer-visible way to ensure this. Thus, the opportunity to overcome this obstacle is to offer

something like

gang scheduling for Cloud Computing.

Bugs in Large-Scale Distributed Systems

One of the difcult challenges in Cloud Computing is removing errors in

these very large scale distributed systems. A



common occurrence is that these bugs cannot be reproduced in smaller

congurations, so the debugging must occur at

scale in the production datacenters.

One opportunity may be the reliance on virtual machines in Cloud

Computing. Many traditional SaaS providers

developed their infrastructure without using VMs, either because they

preceded the recent popularity of VMs or

because they felt they could not afford the performance hit of VMs. Since

VMs are de rigueur in Utility Computing,

that level of virtualization may make it possible to capture valuable

information in ways that are implausible without

VMs.

Scaling Quickly

Pay-as-you-go certainly applies to storage and to network bandwidth, both

of which count bytes used. Computation

is slightly different, depending on the virtualization level. Google AppEngine

automatically scales in response to

load increases and decreases, and users are charged by the cycles used.

AWS charges by the hour for the number of

instances you occupy, even if your machine is idle.

The opportunity is then to automatically scale quickly up and down in

response to load in order to save money,

but without violating service level agreements. Indeed, one RAD Lab focus

is the pervasive and aggressive use of

statistical machine learning as a diagnostic and predictive tool that would

allow dynamic scaling, automatic reaction

to performance and correctness problems, and generally automatic

management of many aspects of these systems.

Another reason for scaling is to conserve resources as well as money. Since

an idle computer uses about two-thirds

of the power of a busy computer, careful use of resources could reduce the

impact of datacenters on the environment,



which is currently receiving a great deal of negative attention. Cloud

Computing providers already perform careful

and low overhead accounting of resource consumption. By imposing per-

hour and per-byte costs, utility computing

encourages programmers to pay attention to efciency (i.e., releasing and

acquiring resources only when necessary),

and allows more direct measurement of operational and development

inefciencies.

Being aware of costs is the rst step to conservation, but the hassles of

conguration make it tempting to leave

machines idle overnight so that nothing has to be done to get started when

developers return to work the next day. A

fast and easy-to-use snapshot/restart tool might further encourage

conservation of computing resources.

Reputation Fate Sharing

Reputations do not virtualize well. One customers bad behavior can affect

the reputation of the cloud as a whole. For

instance, blacklisting of EC2 IP addresses [31] by spam-prevention services may limit which applications can be effectively hosted. An opportunity

would be to create reputation-guarding services similar to the trusted

email services

currently offered (for a fee) to services hosted on smaller ISPs, which

experience a microcosm of this problem.

Another legal issue is the question of transfer of legal liabilityCloud

Computing providers would want legal

liability to remain with the customer and not be transferred to them (i.e.,

the company sending the spam should be

held liable, not Amazon).



Software Licensing

Current software licenses commonly restrict the computers on which the

software can run. Users pay for the software

and then pay an annual maintenance fee. Indeed, SAP announced that it

would increase its annual maintenance fee to at least 22% of the purchase

price of the software, which is comparable to Oracles pricing *38]. Hence, many cloud computing providers originally relied on open source software in part because the licensing model for commercial software is not a good match to Utility Computing.

The primary opportunity is either for open source to remain popular or

simply for commercial software companies to change their licensing structure to better t Cloud Computing. For example, Microsoft and

Amazon now offer pay-as-you-go software licensing for Windows Server and Windows SQL Server on EC2. An EC2 instance running Microsoft

Windows costs $0.15 per hour instead of the traditional $0.10 per hour of the open source version.

A related obstacle is encouraging sales forces of software companies to sell

products into Cloud Computing. Payas-you-go seems incompatible with the

quarterly sales tracking used to measure effectiveness, which is based on

one-time purchases. The opportunity for cloud providers is simply to offer

prepaid plans for bulk use that can be sold at discount. For example, Oracle sales people might sell 100,000 instance hours using Oracle that can be used over the next two years at a cost less than is the customer were to purchase 100,000 hours on their own. They could then meet their quarterly quotas and make their commissions from cloud sales

as well as from traditional software sales, potentially converting this customer-facing part of a company from naysayers into advocates of cloud

computing.



There are many possible advantages of cloud computing, but they may not

apply to all consumers.

Reduced Costs:

Cloud services paid for on a usage basis can be financially advantageous for

a consumer when compared to the outright purchase, or long-term rental,

of what would be a big-budget item. Also, there are reduced operating

costs, because a cloud consumer does not need to house, staff and

maintain their own equipment.

Up to date software:

SaaS consumers can always have the most up-to-date software, because

versioning is controlled centrally by the cloud provider, and when they

make a new release it is automatically available to every user.

This is particularly advantageous for cloud desktops, because deployment

of new software versions can be very costly and time consuming for a large

organisation with many PCs, and because it can therefore be difficult to

ensure that everyone has the same version of the organisation's PC

software applications at any one time.

Improved access:

Cloud computing involves using the Internet, and this can provide access

from multiple locations and many different types of user device.

Advantages



Sharing and co-operation

Cloud services are advantageous, when compared to PCs and local servers,

for activities that require co-operation among distributed groups.

Flexible and infinite scaling

Flexible and infinite scaling can be an advantageous feature of cloud-

computing services, for example to allow for a sudden increase in demand

by the users. This has traditionally been a difficulty for fully owned and self-

managed IT resources, where there can be, for example, one server with a

given, fixed size, and where some of its capacity may be wasted when

demand is low, but where it may be overloaded, resulting in slow response

times, when demand is high.

Simpler capacity sampling

Cloud computing moves the IT capacity-planning role from the consumer to

the cloud provider, and they can be in a better position to optimize the

cloud resources used by their consumers than the consumers themselves

would before their own resources.



Examples

For example, the provider may be able to supply better demand smoothing,

because they can perform capacity planning over a much larger pool of

resources, and for a large group of consumers, whose peak loads will

probably not occur all at the same time.

All cloud services have a dedicated-resource aspect, with consumer-controlled access

to these resources by authorised users, via a secure-access method, such as a login

ID. Also, the resources process data that is private to the consumer and their

associates, which means that it is entered or created by them, although it may be

accessible by others, including the general public.

There are many organisations that supply cloud services, and there is a very wide range

of such services.

Application Software

A range of cloud applications is available, including common small-business applications, such as accounting, and medium-to-large organisation line-of- business or mission-critical applications, such as CRM and ERP. These applications are:

Part of Software as a Service, which is one of the cloud-computing service

models.

Located in a private cloud if the software is supplied to just one consumer or in

a public cloud if any entity needing the software can become a consumer. These are

two of the cloud-computing deployment models. Hosted by an Application Service Provider (ASP).

The authorized users of the hosted software include the organizations staff, and possibly the staff of their associates, such as customers and suppliers. The private data includes confidential information entered by the users, such as



financial-transaction amounts, but there could also be a publicly-accessible aspect, such as a shopping-cart feature that can be used by visitors to a retail organizations website.

Third Party application provider

ASPs may host software that they have developed themselves, or

software developed by others. Some market-leading software systems,

such as SAP and Sharepoint, are available from third-party ASPs.

Database

Database as a Service (DbaaS) hosts cloud databases, and virtually all major database platforms are available in the cloud, including Amazon SimpleDB and Amazon Relational Database Service. The private data for these services consists of the records stored in the database.

Email

Email computing involves two aspects:

Composing, reading and organising emails.

Sending and receiving them via the Internet.

The first of these can be done on a user-device, such as a PC, in which case it is not part of cloud computing, or it can be done at the website of an ISP, in which case it is part of cloud computing. The second aspect is part of cloud computing in both cases. For PC-based email, composing and reading emails, and organizing them in folders, is done with software running on a PC, and all of the permanent storage, such as for the inbox, sent and other folders, and address books, is allocated on the PC. This is not cloud computing, because the email software and storage are not accessed via the Internet, but directly on the PC, even though the send and receive software is hosted by an ISP. The latter software is part of cloud computing, and the



private data for this computing consists of the received and sent emails stored, perhaps temporarily, by the ISP prior to being retrieved for reading on the PC, or sent via the Internet. For web-based email, or webmail, such as Gmail, the data is stored for the consumer in disk space allocated by the service provider, and emails are composed, read and organised using software hosted by the provider at their site. The private data for this computing includes all emails, folders and address books. Webmail is part of Software as a Service. In both cases, a PC, or other user device, is a cloud client used to access the services.

Office-productivity software

Office-productivity software, such as Google Docs, is available as a cloud

service. The private data for this software consists of the user's created

artefacts, such as word-processor documents and spreadsheet models, which

are stored and managed on the provider's infrastructure. This is part

of Software as a Service.

Software production

Development environments

There are cloud services, such as the Azure Services Platform, that provide software-development environments. These are part of Platform as a Service, which is one of the cloud-computing service models. The private data for these services consists of all development information, which would be accessible only by the consumers and their authorized users, including any third-party developers.

Customer support

There are cloud services, such as Get Satisfaction, that provide self-help and developer support for the customers of a software company. This



support is obtained and entered at a website that hosts and sells the companys products. This is a service for the software company, and the private data includes the domain names of the websites for which support is required.

Storage Service

Disk storage space can be rented from some cloud providers, and consumers of these services can upload software or data, for example by using the service for backup of client-device information. The private data would consist of the uploaded material. The infrastructure is:

Known as Storage as a Service, and it is part of Infrastructure as a Service,

which is one of the cloud-computing service models.

Hosted by a Storage Service Provider.

Co-oparation and Community service

There are cloud services that use the remote connectivity features of the Internet to support distributed co-operative activities, such as systems support, project work or voice and video communication. Examples of such services include:

Screen-sharing systems, such as LogMeIn and Mikogo that can be used for remote

support or co-operation on projects among geographically distributed participants.

Teleconferencing systems, such as Skype.

For these systems, client software needs to be installed on a user device, and this isn't part of cloud computing, but there is also central storage of a user's identity, so that they can connect with others. This storage and the associated connectivity software are part of cloud computing. The private data for this service includes the consumers identity.

Websites

Creation and hosting

There are cloud services that provide website creation and hosting.



The private data for the consumers of these services includes the websites content, and the dedicated resources would include a CMS, so that they can manage the website, and possibly a CRM, so that they can manage customers and purchases.

Feedback

There are cloud services for website operators, that allow visitors to a website to provide feedback to these operators, and that allow the operators to analyse this feedback. The private data includes the consumers domain names for which feedback is required.

Visitor statistics

There are cloud services, such as Google Analytics, that provide website visitor statistics to the operators, and that provide analysis of these statistics. These are consumed by website operators, and the private data includes the consumers domain names for which statistics are required.

Payment

There are cloud services, such as PayPal, that allow website visitors to pay for anything purchased at the site. These are consumed by website operators, and the private data includes information on the consumers connected bank accounts, so that transfers of accumulated payment amounts can be made.

Personal uses

Cloud storage

Anyone with Internet access can rent cloud storage and upload their

personal data, for backup or sharing purposes. This is known as

a personal cloud, and it is part of Infrastructure as a Service. For example, with photos in the cloud, a family can share them with

members and friends that are in distributed locations, in a way that

couldnt happen with data on their PCs. The private data consists of the



uploaded information, and the authorised users consist of all those given

access to this information.

Potentially, this type of service could have the largest group of tenants

across all providers, because any member of the general public with a

device that can access the Internet can become a consumer, if only to

backup data.

Internet TV

Internet TV, also known as cloud TV, is a cloud service. The private data for the consumers of these services includes their multicast address.

Online banking

Online banking is an example of SaaS for the banks customers, and the private data for each consumer includes their bank account transaction information. Besides desktop and portable computers, the cloud clients used to access this service include ATMs, online or mobile wallets, and point-of-sale terminals.

Social media and networking

Media and networking sites, such as Facebook and LinkedIn, are part of cloud computing. The private data for the consumers includes uploaded information, and this is accessible by the authorized network consisting of their friends or colleagues.

Synced data

Different client devices owned by the same consumer can have their data synchronized, or synced, via the cloud, so that each device can access the data produced by all the other devices. This is done by automatically backing up the data of each client using cloud infrastructure. One example of this for personal use is the iCloud, which provides cloud storage for an individual's music downloads from the iTunes Store in such a way that they can be accessed from any of their client devices. In this



case, the private data consists of the tunes that are automatically gathered for the consumer onto their cloud storage, regardless of how they are purchased.

Online retailing

There are cloud services, such as eBay, that allow individuals to sell items on the Internet. The private data for these services includes details of the consumers sale items.

Blogging

There are cloud services, such as WordPress, that enable individuals to create and maintain a weblog. The consumers of these services control access by allowing only themselves to contribute blog topics and to respond to visitor comments, or by authorising others to do so. The private data includes the:

1. Topics that are entered from time to time.

2. Comments entered by blog visitors, which can be published or

suppressed by the consumer.

3. Responses of the consumer.

4. Details of who can read or contribute to the blog, which can be the

general public, or an exclusive group.

Peer-to-peer file sharing

Cloud computing involves using a network of remote servers hosted on the Internet. These servers can be kept in a datacentre operated by a single cloud provider, but they can also be part of a distributed P2P network that shares resources via the Internet. In such a network, all participating systems are peers, which means that they are both clients and servers, and so their users are both service consumers and service providers. For example, P2P file-sharing is part of cloud computing. At any one time, the group participating in this service consists of the users of all devices



with the same file-sharing software, such as BitTorrent, that are on-line at any one time. For these participants, the service is the mutual sharing of files, and this sharing is:

1. Consumed by each participant by uploading from another participant, or

downloading to another participant.

2. Provided by each participant by making available some of the files on

their own device, for downloading or uploading.

For the participants, as:

A. Consumers, the:

1. Private data consists of the files on their own device that they allow to be shared.

2. Dedicated resources include their file-sharing software, which is used for the

uploading and downloading of files, and to identify them as part of the network. 3. Controlled access consists of allowing the use of their client device for uploading

to, or downloading from, the other participants.

B. Providers, they host on their own behalf.

Collaborative distributed computing

The Internet services that control collaborative, distributed computing, such as GIMPS and SETI@home, are part of cloud computing.This is also known as volunteer computing. These services divide up the computation into small parts that are then distributed to the participating user devices over the Internet. After carrying out its part of the task, a device sends the results back to the cloudbased control as a contribution to the whole process. The consumers of these services are the participants whose user devices carry out parts of the computation. The private data for each consumer consists of their registration info

cloud computing project

Documents