3. Instructor Background Information
Role@Star Storage :
Chief Delivery Officer for Infrastructure Solutions & Cloud Business Unit
Role@MCloud 1
Leaded the delivery team from Star Storage
Background
IT and Business Management
Business Process Management
Project Management
IT Security
Accredited Tier Specialist for Data Centers Operations (Uptime Institute)
Cloud Computing Certified Professional
4. Ground Rules
There are not any!…as long as you keep your mobiles
on mute and laptop/tablet closed
Ask questions, comment and challenge at anytime!
I don’t have all the answers, however might be able to
get it later.
Understand the time limitation -Rome was not built
in a day
6. Timetable
Session 1 - 05 March:
Session 1 - 10 : 00 AM – 11:20 AM
Coffee break – 11:20 AM – 11:40 AM
Session 2 – 11:40 AM – 13:00 PM
7. Session 1 Overview
A Brief History of Cloud Computing
Fundamental Terminology and Concepts
Characteristics of a cloud
Roles and Boundaries
Cloud Delivery Models
Cloud Deployment Models
Benefits of Cloud Computing
Challenges of Cloud Computing
Business Cost Metrics
Service Level Agreements (SLAs)
The world has chaged !
9. “When asked what “the cloud” is, a
majority respond it’s either an actual
cloud, the sky, or something related to
wheather”
Citrix Cloud Survey Guide
10. Cloud Computing Defined
“Cloud computing is a specialized form of
distributed computing that introduces
utilization models for remotely provisioning
scalable and measured IT resources.”
11. Cloud Defined
“A cloud is a distinct and remote IT
environment designed for the purpose of
remotely provisioning scalable and
measured IT resources.”
13. Overview
The idea of computing in a “CLOUD” traces back to the origins of utility
computing – a concept published in 1961 by scientist John McCarty:
“If computers of the kind I have advocated become the computers of the future,
then computing may someday be organized as a public utility just as the
telephone system is a public utility. … The computer utility could become the basis
of a new and important industry.”
In 1969, Leonard Kleinrock, a chief scientist of the Advanced Research
Projects Agency Network or ARPANET, stated:
“As of now, computer networks are still in their infancy, but as they grow up and
become sophisticated, we will probably see the spread of ‘computer utilities’ …”.
14. Overview
Mid-1990s, various forms of Internet-based computer utilities:
Search Engines: Yahoo!, Google
E-mail Services: Hotmail, Gmail
Social Media: My Space, Facebook, YouTube, Twitter, Linkedin
Term “Network Cloud” or “Cloud” was introduced in early 1990s in networking industry
In 2002, Amazon.com launched the Amazon Web Services (AWS) platform, a suite of
enterprise-oriented services that provide remotely provisioned storage, computing
resources, and business functionality
In 2006 the term “cloud computing” emerged in the commercial arena.
Amazon launched its Elastic Compute Cloud (EC2) services that enabled organizations to
“lease” computing capacity and processing power to run their enterprise applications
Google Apps also began providing browser-based enterprise applications in the same year,
and three years later, the Google App Engine became another historic milestone.
15. Overview
Cloud computing emerged from a combination of business drivers
and technology innovations.
Business drivers:
Capacity Planning
Cost reduction and Operating Overhead
Organizational Agility
Technology Innovations:
Grid Computing Technology
Clustering Technology
Virtualization Technology
16. Business Drivers: Capacity Planning
Capacity planning is an unavoidable responsibility for most IT
enterprises, requiring that future demands on IT infrastructure be
planned for and accommodated.
Capacity planning can be very challenging because it can
require estimating usage load fluctuations.
There is a constant need to balance peak usage requirements
without unnecessarily over-spending on IT infrastructure.
To accommodate maximum usage loads may require too high
of an investment. To moderate the investment may result in lost
transactions and other usage limitations due to lower usage
thresholds.
17. Business Drivers: Capacity Planning
Different capacity planning strategies exist :
Lead Strategy – adding capacity to an IT resource in anticipation of demand
Lag Strategy – adding capacity when the IT resource reaches his full capacity
Match Strategy – adding IT resource capacity in small increments, as demand
increases
18. Business Drivers: Cost Reduction
and Operating Overhead
Two costs need to be accounted for:
the cost of acquiring new infrastructure
The cost of its going ownership (TCO)
Common forms of infrastructure-related operating overhead
include the following:
technical personnel required to keep the environment operational
upgrades and patches that introduce additional testing and
deployment cycles
utility bills and capital expense investments for power and cooling
security and access control measures that need to be maintained
and enforced to protect infrastructure resources
administrative and accounts staff that may be required to keep
track of licenses and support arrangements
19. Business Drivers: Organization Agility
Organizational agility represents the responsiveness of an organization in
the face of business chance.
“… so even elephants can walk on a tightrope”
20. Technology Innovations:
Grid Computing
Grid computing emerged in the 90’s to introduce the
concept of “computing as a networked utility”.
A computing grid provides a platform in which computing
resources are organized into one or more logical pools.
With a grid you could plug into a pool of shared
computing power the same way you would plug an
appliance into a shared power grid
This concept led to the notion of “pay-as-you-go”
computing and further formed the basis of “elasticity” –
both of witch established fundamental characteristics of
a cloud
21. Technology Innovations:
Web/Clustering Architectures
Because Web Applications were commonly made available to a wide
public, they often became demand-driven and tended to be “spiky” in
their usage loads.
The back-end technology architectures that evolved in support of Web-
based applications therefore introduced the need for:
Load balancing
Server farms
Clustered servers
Clustered databases
22. Technology Innovations:
Virtualization Technology
Virtualization is an established technology that has enabled
hardware owners to repeatedly leverage physical servers for
wide, concurrent usage.
Virtualization further helped realize the notion of “server
elasticity” by allowing one physical server to host a variable
number of “virtual” servers.
Virtualization is a key technology in modern cloud
computing.
24. Overview
Before we can discuss the details of cloud computing, we need to first
establish some fundamentals terms and concepts :
IT Resource
Virtualization
Scaling
Cloud
On-Premise
Service
Cloud Service
Service Agent
25. IT Resource
An IT resource is a physical or virtual IT-related artifact (software or
hardware).
The following are common types of IT resources:
• physical server
• software program
• storage device
• virtual server
• service
• network device
26. Virtualization
Virtualization allows physical IT resources to provide multiple virtual
images of themselves so that their underlying processing capabilities
can be shared individually by multiple consumers.
The owner of the physical IT resource maintains centralized
administrative control and intentionally hides implementation details fro
consumers of the virtual IT resources.
This abstraction of the physical IT resource allows consumers to use the
provided virtual IT resources without any required knowledge of how the
underlying physical IT resource exists or operates.
As consumer usage demands fluctuate, the owner of the physical IT
resource can scale it accordingly.
27. Virtualization
For example, a physical computer will often contain a single installation
of an operating system that can be used by a single consumer.
Through virtualization, the same computer can provide multiple images
of the same operating system installation that can be independently
used by multiple consumers.
The owner of the physical computer can retain administrative control
of the computer hardware and the base operation system
environment.
Consumers of the virtual operating system images can independently
configure and control their respective virtual environments, but are not
given access to (nor require access to) the underlying physical
environment.
28. Virtualization
Virtualization is an established area of technology that
emerged long before cloud computing.
Within cloud environments, virtualization technology is primarily
utilized to replicate multiple virtual images of the same physical
server for remote access by consumers.
A virtual server is a form of virtualization software that emulates
a physical computer (a physical server).
Each physical server can host multiple virtual servers.
To a cloud consumer, a virtual server appears as an
independent physical server.
29. Scaling
Scaling, from an IT resource perspective, represents the ability of the IT
resource to gracefully handle increased or decreased usage demands.
The following are scaling –related terms used in these courses:
• horizontal scaling
scale out
scale in
• vertical scaling
scale up
scale down
30. Scaling (Horizontal)
Horizontal scaling refers to the allocation or releasing of resources of
the same type. The horizontal allocation of resources is referred to as
scaling out and the horizontal releasing of resources is referred to as
scaling in.
Horizontal scaling is a common form of scaling within cloud
environments.
31. Scaling (Vertical)
Vertical scaling occurs when an existing resource is
replaced by another.
The replacing of an IT resource with another that has
a higher capacity is referred to as scaling up and the
replacing an IT resource with another that has a lower
capacity is referred to as scaling down.
Vertical scaling is less common in cloud environments
due to the downtime required while the replacement
is taking place.
33. Cloud
A cloud is a distinct and remote IT environment designed for
the purpose of remotely provisioning scalable and measured
IT resources.
IT resources are provided by a cloud for consumers to
access remotely, from outside the cloud perimeter.
Consumers may or may not know the exact physical location of the IT
resources provided by a cloud.
Although a cloud will commonly be based on Web protocols and
technologies, it is not necessary for a cloud to be Web-based. A cloud
can exist with the use of any remote access protocols that allow for
access to its IT resources.
34. Cloud
Not every IT resource that resides inside a cloud needs to be made
directly available to consumers.
A cloud-based IT resource can be remotely accessed or it can support
the remote access of other cloud-based IT resources.
When an IT resource is made available to external consumers, it is
accessible as a cloud service (as explained in the upcoming Cloud
Service section).
35. Cloud Example
A cloud hosting eight IT resources: three virtual servers, two cloud
services, and three cloud storage devices.
36. On-Premise
The term on-premise (or “on-premises”) is used to qualify an IT resource
that is not remotely accessible via a cloud, but instead resides within an
internal IT enterprise environment.
It is important to note that very often cloud-based IT resources are
invoked by or communicate with on-premise IT resources.
For example, an IT resource may be moved from an on-premise
environment to a cloud, or vice versa.
38. Service
From an implementation perspective, a service is a software
program that can be remotely invoked via a published technical
interface (or API) referred to as a service contract.
When a software program invokes and interacts with a service, it is
labeled as a service consumer.
Services acting as service consumers can invoke other services.
When two or more services participate to complete a given task,
the services from a service composition.
A service can reside on-premise or in a cloud. In the latter case, it is
further qualified as a cloud service (as explained in the following
Cloud Service section).
39. Cloud Service
The term “service” within the context of cloud computing is very broad.
From a cloud computing perspective, any remotely accessible IT resource
is classified as a service.
A cloud service can therefore be considered an IT resource made
remotely accessible via a cloud.
Note that even though a cloud service exists as an IT resource, it may
further provide access to other cloud-based IT resources.
Note that a cloud service can exist as a software program that acts as an
endpoint or access point to a larger application, platform or environment.
From a consumer perspective, the larger application, platform or
environment itself (and in its entirety) may be considered the “service”.
40. Cloud Service
A cloud service can exist as:
• A traditional service (such as a Web
service or a REST service) accessed via a
published contract and messaging.
• A software program remotely accessed
via other means (such as communicating
with a software program on a server using
a proprietary protocol)
41. Service Agent
A service agent is an event-driven program capable of transparently
intercepting and processing messages sent to or from services.
Depending on the development platform you are working with, service
agents may be called “filters”, “listeners”, “interceptors”, “handlers”,
etc.
Most modern runtime environments (and operating systems) provide a
set of system service agents, but service agents can also be custom-
developed.
Service agents do not have a technical interface (or service contract)
and are therefore not explicitly invoked.
42. Service Agent
Service agents are depicted using the rectangular block symbol.
Common functions performed by service agents include routing,
logging, validation, and security related processing.
Service agents are important to cloud computing, especially for
providing runtime monitoring and load balancing functions.
44. Overview
Let’s revisit the definition of cloud computing:
Cloud computing is a specialized form of distributed computing that
introduces utilization models for remotely provisioning scalable and
measured IT resources.
Let’s revisit the definition of a cloud:
A cloud is a distinct and remote IT environment designed for the
purpose of remotely provisioning scalable and measured IT resources.
In order to remotely provision scalable and measured IT resources in an
effective manner, an IT environment requires a specific set of
characteristics.
These characteristics need to exist to a meaningful extent for the IT
environment to be considered an effective cloud.
45. Cloud Characteristics
This section is dedicated to individually describing the following six cloud
characteristics :
• On-Demand Usage
• Ubiquitous Access
• Multitenancy
• Elasticity
• Measured Usage
• Resiliency
46. On-Demand Usage
A cloud consumer can unilaterally access cloud-based IT resources
giving the cloud consumer the freedom to self-provision these IT
resources.
Once configured, usage of the self-provisioned IT resources can be
automated, requiring no further human involvement by the cloud
consumer or cloud provider.
This results in an on-demand usage environment.
47. Ubiquitous Access
Ubiquitous access represents the
ability for a cloud service to be widely
accessible. Establishing ubiquitous
access for a cloud service can require
support for a range of transport
protocols, interfaces and security
technologies.
To enable this level of access generally
requires that the cloud service be
tailored to the particular needs of
different cloud service consumers.
48. Multitenancy (and Resource
Pooling)
Multitenancy is a characteristic of a software program that enables an
instance of the program to serve different consumers (tenants), each
of which is isolated from the other.
A cloud provider pools its IT resources to serve multiple cloud service
consumers by using the multitenancy model.
Cloud-based multitenancy models frequently rely on the use of
virtualization technologies.
Through the use of multitenancy technology, IT resources can be
dynamically assigned and reassigned, according to cloud service
consumer demands.
49. The figure on the left is an example of single tenancy in that each
cloud service consumer is provided a separate underlying IT
resource instance (in this case, a storage device).
The figure on the right illustrates multitenancy, whereby a single
instance of an IT resource is provided to both cloud service
consumers, each likely unaware that the IT resource is being shared.
50. Elasticity
Elasticity is the automated ability of a cloud to gracefully and
transparently scale IT resources, as required in response to runtime
conditions or as predetermined by the cloud consumer or cloud
provider.
Elasticity is often considered a core justification for the adoption of
cloud computing, primarily due to the fact that it is closely associated
with the Reduced Investment and Proportional Costs benefit.
Cloud providers with the vast resources can offer the greates range of
elasticity.
52. Measured Usage
Measured usage represents the ability of a cloud platform to keep
track of the usage of its IT resources by cloud consumers.
Based on what is measured, the cloud consumer is charged only for
the IT resources actually used and/ or for the timeframe where access
to the IT resources was required.
Measured usage is not limited to tracking statistics for billing purposes. It
also encompasses the general monitoring of IT resources and related
usage reporting (to both cloud provider and cloud consumers).
53. Measured Usage
A typical application
of measured usage
within a cloud is the
monitoring and
collection of runtime
data by the cloud
provider to be used
for cloud consumer
billing purposes, as
demonstrated here.
54. Resiliency
Resilient computing is a form of failover that distributes redundant
implementations of IT resources across physical locations.
IT resources can be pre-configured so that if one becomes deficient,
processing is automatically handed over to another redundant IT
resource.
Within cloud computing, resiliency can refer to redundant IT resources
within the same cloud (but in different physical locations) or across
multiple clouds.
Cloud consumers can increase the reliability and availability of cloud-
based IT resources.
55. Resiliency
For example, Cloud A provides Cloud
Service A as part of a failover system
that encompasses a redundant
implementation of Cloud Service A on
Cloud B. If Cloud Service A on Cloud A
fails, then Cloud Service A on Cloud B is
automatically provisioned transparently
to Cloud Service Consumer A.
Each cloud has a specific level of
reliability and availability that it
guarantees for Cloud Service A. By
spanning the failover system across
both clouds, the overall reliability and
availability will be higher than the
maximum reliability and availability of
either cloud.
58. Service Consumer
As described earlier in the Fundamental Terms & Concepts section,
when a software program accesses a service it is labeled as a
service consumer.
A service consume is therefore a temporary runtime role assumed
by a software program.
A service itself may assume the role of a service consumer when it
invokes and interacts with another service (as part of a service
composition).
To distinguish between service consumers that access on-premise
and cloud-based services, those that access cloud services are
further qualified as cloud service consumers (as explained next).
59. Cloud Service Consumer
The cloud service consumer is a temporary runtime role assumed by
a software program when it accessed a cloud service.
The following are common types of cloud service consumers:
• software programs and services capable of remotely accessing cloud
services with published service contracts (such as Web services)
• workstations, laptops and mobile devices running software capable of
remotely accessing other IT resources positioned as cloud services (such
as virtual servers)
61. Cloud Provider
A cloud provider is the organization that owns
(provides) a cloud.
One cloud provider may own multiple clouds.
When relevant, diagrams in these courses
indicate the cloud providers of depicted clouds.
When a cloud is not further labeled with a cloud
provider, it is still implied that the cloud has a
cloud provider.
62. Cloud Consumer
A cloud consumer is an organization or a human that uses a cloud
service consumer to access a cloud service.
The diagrams in these courses do not often explicitly label symbols
as “cloud consumers”.
Instead, it is generally implied that organizations or humans shown
remotely accessing cloud-based IT resources are considered cloud
consumers.
63. Cloud Consumer
In this example, Organization A is
the cloud consumer
In this example, the illustrated
human is the cloud consumer
64. Cloud Service Owner
A cloud service owner is the person or organization that legally owns
a cloud service.
The cloud service owner can be either the cloud consumer or the
cloud provider of the cloud within which the cloud service resides.
For example, if Cloud X hosts Cloud Service A then either the cloud
consumer of Cloud X or the cloud provider of Cloud X can be the
Cloud Service Owner of Cloud Service A. (See the upcoming
diagrams).
65. Cloud Service Owner
A cloud consumer can be a cloud service owner when it has
deployed its own service in a cloud.
A common example of this is when the cloud consumer uses a PaaS
offering to develop and deploy its own cloud service (as explained
in the upcoming Cloud Delivery models section).
66. Cloud Service Owner
A cloud provider can be a cloud service owner when it deploys its
own service in a cloud (typically for use by other cloud consumer)
A common example of this is when the cloud providers make
services commercially available as SaaS offerings (as explained in
the upcoming Cloud Delivery models section).
67. Cloud Resource Administrator
A cloud resource administrator is the person or organization
responsible for administering a cloud-based IT resource (including
cloud services).
The cloud resource administrator can be (or belong to) the cloud
consumer or cloud provider of the cloud within which the cloud
service resides.
Alternatively, it can be (or belong to) a third-party organization
contracted to administer the cloud-based IT resource.
For example, a cloud service owner could contract a cloud
resource administrator to administer a cloud service.
68. Cloud Resource Administrator
A cloud resource administrator can be with a cloud consumer
organization and can administer remotely accessible IT resources that
belong to the cloud consumer.
69. Cloud Resource Administrator
A cloud resource administrator can be with a cloud provider
organization for which it can administer IT resources (internally and
externally available) belonging to the cloud provider.
70. Cloud Resource Administrator
The reason we don’t call the cloud resource administrator a cloud
service administrator, is because this person or organization may be
responsible for administering cloud-based IT resources that don’t
exist as cloud services.
For example, if the cloud resource administrator belongs to (or is
contracted by) the cloud provider, IT resources not made remotely
accessible may be administered by this role (and these types of IT
resources are not classified as cloud services).
71. In this scenario, the cloud provider’s cloud resource administrator
accesses an internal IT resource (the physical server) that hosts
externally accessible IT resources (the virtual server and the cloud
service) available to the cloud consumer.
72. Cloud Resource Administrator
Note that the cloud resource administrator is a role assumed
by a human (or a group of humans). It is not a role assumed
by a software program.
In diagrams, when we show the workstation symbol
remotely accessing an IT resource (such as the virtual server
in the diagram to the right), we refer to this as the “cloud
resource administrator”.
However, it is implied that the workstation being used by the
human to perform the administration task is using a software
program that technically is acting as a cloud service
consumer.
73. Roles Summary
Runtime roles assumed by software programs:
• service consumer (when a software program accesses an on-premise
service)
• cloud service consumer (when a software program accesses a cloud service)
Roles assumed by people/ organizations:
• cloud consumer (when a person/ organization uses IT resources provided by
a cloud)
• cloud provider (the person / organization that owns/ provides a cloud)
• cloud resource administrator (the person/ organization responsible for
administering a cloud-based IT resource)
74. Organizational Boundary and Trust
Boundary
An organizational boundary represents the physical perimeter that
surrounds a set of IT resources owned by a specific organization.
This means that an organizational boundary does not represent the
boundary of an actual organization (only a set of organizational IT assets
represented by IT resources).
Organizational boundaries are generally used to indicate regions or
environments that are under the control of the organization.
Incorporating cloud computing into an IT enterprise can require that IT
resources be placed outside of an organizational boundary.
This can result in a loss of control of an organization’s IT resources.
75. Organizational Boundary and Trust
Boundary
An organization acting as a
cloud consumer has its own
organizational boundary.
A cloud provided by a cloud
provider will have its own
organizational boundary.
76. Organizational Boundary and Trust
Boundary
A trust boundary establishes a logical perimeter wherein IT
resources are trusted from a security perspective.
The IT enterprise within an organization can establish an
internal trust boundary that encompasses its own IT
resources.
77. Organizational Boundary and Trust
Boundary
Cloud-based IT resources that are used by a cloud consumer reside
outside of the cloud consumer’s organizational boundary.
To use the IT resources, the cloud consumer will generally need to
trust them.
As a result, the cloud consumer’s
trust boundary is expanded beyond
its organizational boundary to
encompass the cloud.
79. Overview
A cloud delivery model represents a specific combination of IT
resources offered by a cloud provider.
Depending on the types of IT resources required by a cloud consumer,
three common delivery models are used:
• Infrastructure-as-a-Service (IaaS)
• Platform-as-a-Service (PaaS)
• Software-as-a-Service (SaaS)
Variations of these delivery models can also exist. Note that a cloud
delivery model is also referred to as a cloud service delivery model
because each model is classified as a different type of cloud service
offering.
80. Infrastructure-as-a-Service (IaaS)
The IaaS delivery model provides a self-contained IT environment
comprised of infrastructure-centric IT resources.
This environment can include hardware, network, connectivity,
operating systems, and other “raw” IT resources.
In contrast to traditional hosting or outsourcing IT environments, with
IaaS, IT resources are typically virtualized and packaged into
bundles that simplify up-front runtime scaling and customization of
the infrastructure.
81. Infrastructure-as-a-Service (IaaS)
Cloud consumers are provided with a range of contractual guarantees
by the cloud provider, pertaining to characteristics such as capacity,
performance, availability, etc.
82. Infrastructure-as-a-Service (IaaS)
The IT resources provided by IaaS are generally raw and not
preconfigured, placing the operational responsibility upon the cloud
consumer.
The IaaS delivery model is therefore used by cloud consumers that
require a high level of control over the cloud-based environment they
intend to create.
Sometimes cloud providers will contract IaaS offerings from other cloud
providers in order to scale their own cloud environments.
The types and brands of the IT resources provided by IaaS products
offered by different cloud providers can vary.
83. Platform-as-a-Service (PaaS)
The PaaS delivery model provides a pre-defined cloud environment
with already deployed and configured IT resources suitable for the
development and deployment of applications.
Three common reasons cloud consumers use PaaS:
1. The cloud consumer wants to extend on-premise environments into the
cloud for scalability and economic purposes.
2. The cloud consumer uses the ready-made environment to entirely
substitute an on-premise environment.
3. The cloud consumer wants to become a cloud provider and deploys its
own cloud services that are made available to other external cloud
consumers.
84. The PaaS delivery model relies on (and is primarily defined by) the
usage of a ready-made environment that establishes a set of pre-
packaged products and tools used to support the entire delivery
lifecycle of custom applications.
The cloud service consumer is given
access to a ready-made environment on
a virtual server (also with contractual
guarantees) but will typically not be given
knowledge of any further implementation
details.
85. Software-as-a-Service (SaaS)
The SaaS delivery model generally represents a product that exists
as a shared cloud service offered by a cloud provider to cloud
consumers.
The cloud consumer leases the cloud service from the cloud
provider, who is responsible fro maintaining the cloud service’s
underlying IT resources.
SaaS offerings are typically provided so that cloud consumers can
gain access to the cloud service with minimal up-front effort.
86. Software-as-a-Service (SaaS)
The cloud service consumer is given access the cloud service
contract, but not to any underlying IT resources or implementation
details.
87. Software-as-a-Service (SaaS)
Unlike with IaaS and PaaS models, the SaaS delivery model does not
provide cloud consumers with administrative control over the cloud
service or its IT resources.
Cloud consumers are granted usage control over the cloud service
– administrative control is retained by the cloud provider.
89. Administrative Control
The three delivery models differ with respect to the functionality and the
level of administrative control provided to cloud consumers.
90. Activities Control
Typical activities carried out by cloud consumers and cloud providers in
relation to the cloud delivery models
91. Administrative Control - IaaS
With the IaaS delivery model:
• The cloud provider will typically have full administrative control over the
physical hardware, physical network, storage devices, and virtualization
platforms.
• The cloud consumer will typically have full or partial administrative
control over virtual servers, databases, cloud service implementations,
and security settings.
92. Administrative Control - PaaS
With the PaaS delivery model:
• The cloud provider will typically have full administrative control over all
items listed under the IaaS model, plus virtual servers and databases.
• The cloud consumer’s administrative control is limited to the ready-
made environment(instead of accessing server settings directly,
administrative configuration are made via custom front-end provided
by the ready-made environment).
93. Administrative Control - SaaS
With the SaaS delivery model:
• The cloud provider will typically have full administrative control over all
items listed under the IaaS model, plus virtual servers and databases
and often the service implementation itself.
• The cloud consumer’s administrative control is limited to service
implementation which can be configured via a custom front-end.
94. Combining Cloud Delivery Models
As pointed out with each of the three preceding scenarios, there
are common steps to realizing each of the three cloud delivery
models.
This highlights a natural layered relationship between the three
delivery models providing cloud providers with the option of
establishing one cloud delivery model by leveraging IT resources
from another.
The following pages explore common combinations of cloud
delivery models.
95. IaaS +PaaS
To set up a PaaS environment a
cloud provider can leverage
physical and/ or virtual servers
provided by an existing IaaS
environment.
The PaaS ready-made
environments are built upon
virtual servers and physical
servers provided by a separate
IaaS environment.
96. IaaS +PaaS
The decision by a cloud provider to lease IT
resources from another cloud provider can be
economical or it may be influenced by cloud
consumer requirements. For example, a cloud
consumer may have a legal requirements for
data to be physically stored in a specific region
(for which the cloud provider needs to contract
a different cloud provider).
97. IaaS + PaaS +SaaS
All three cloud delivery models can be combined to establish layers
of IT resources that build upon each other.
Using the ready-made environment provided by PaaS, a cloud
consumer organization can develop and deploy its own SaaS cloud
service that it can then make available as a commercial product.
98. The SaaS product is developed using a
PaaS ready-made environment and
implemented upon virtual severs and
physical servers provided by a
separate IaaS environment.
101. Overview
A cloud deployment model represents a specific type of cloud
environment, primarily distinguished by ownership and size.
There are four common deployment models:
• Public Cloud
• Community Cloud
• Private Cloud
• Hybrid Cloud
(Variations of these deployment models can also exist)
102. Public Cloud
A public cloud is a publically accessible cloud environment owned by
a third-party cloud provider.
The IT resources (usually offered via the previously described delivery
models) on public clouds are generally offered to cloud consumers at
a cost.
The cloud provider is responsible for the creation and on-going
maintenance of the public cloud and its IT resources.
105. Community Cloud
A community cloud is similar to a public cloud except that its access is
limited to a specific community of cloud consumers.
The community cloud may be jointly owned by the community
member or it may be owned by a third-partu cloud provider that
provisions a public cloud with limited access.
The member cloud consumers of the community typically share the
responsibility for defining and evolving the community cloud.
However, membership in the community does not necessarily
guarantee access or control to the cloud’s IT resources.
106. An example of a “community of organizations accessing IT
resources from a community cloud.
107. Private Cloud
A private cloud is owned by a single organization.
Private clouds enable an organization to use cloud computing
technology as a means of centralizing access to IT resources by different
parts of the organization.
The use of a private cloud can change how organizational and trust
boundaries are defined and applied.
The actual administration of a private cloud environment may be
carried out by internal or outsourced staff.
108. Private Cloud
External private clouds can effectively extend on-premise
infrastructure to IT resources that are physically isolated in the private
cloud environment through the use of a virtual primate network
(VPN).
109. Private Cloud
With a private cloud, the same organization is technically both the
cloud consumer and cloud provider.
In order to differentiate these roles:
• a separate organizational department typically assumes the
responsibility for provisioning the cloud (and therefore assumes the
cloud provider role)
• departments requiring access to the private cloud assume the cloud
consumer role
110. Hybrid Cloud
A hybrid cloud is a cloud environment of two or more different
cloud deployment models.
For example, a cloud consumer may choose to deploy cloud
services processing sensitive data to a private cloud and non-
sensitive cloud services to a public cloud.
The result of this combination is a hybrid deployment model.
Hybrid deployment models can be complex and challenging to
create and maintain.
111. An organization using a hybrid cloud
model, which utilizes both a private
cloud and a public cloud.
113. Benefits of Cloud Computing
The following represent the primary benefits of cloud
computing:
• Reduced Investment and Proportional Costs
• Increased Scalability
• Increased Availability and Reliability
114. Reduced Investment and
Proportional Costs
By using virtualization, a cloud provider can offer the same IT resource to
multiple cloud consumers.
Cloud consumers that use cloud-based IT resources can generally lease
them with a pay-for-use model.
With this model, cloud consumers pay a usage fee for only the amount
of the IT resource actually used, resulting in directly proportional costs.
This gives an organization access to IT resources without having to
purchase its own, resulting in reduced investment requirements.
115. Reduced Investment and
Proportional Costs
By lowering required investments and incurring costs that are
proportional to their needs, cloud consumers can scale their IT
enterprise effectively and pro-actively.
As an example, this chart compares the
costs of on-premise IT resources with the
costs of cloud-based IT resources over a
three-year period.
116. Increased Scalability
IT resources can be flexibly acquired from a cloud provider, almost
instantaneously and at a wide variety of usage levels.
By scaling with cloud-based IT resources, cloud consumers can
leverage this flexibility to increase their responsiveness to foreseen
changes and unforeseen changes.
This holds true for when a cloud consumer needs to scale IT
resources, based on current requirements.
117. Increased Scalability
The depicted example illustrates the variation of demand for an
application server during a period of 24 hours, measured in concurrent
users.
Assuming one server from a given cloud provider is
able to handle 2,000 concurrent user, the cloud
consumer can adjust the usage as necessary (in this
case between 1 and 5 servers) and pay only for the
hours of server usage.
118. Increased Availability and
Reliability
An IT resource with increased availability is available for longer periods of
time (for example, 22 hours out of a 24 hour day).
An IT resource with increased reliability is able to better avoid and recover
from exception conditions.
Cloud providers generally offer resilient IT resources for which they are able
to guarantee high levels of availability.
Cloud environments can be based on a modular architecture that provides
extensive failover support to further increase reliability.
Note that availability and reliability are explained in detail in the Service
Level Agreements section.
119. Increased Availability and
Reliability
In the upcoming example, a cloud transparently provides increased
availability and reliability.
During the two illustrated message exchanges, the cloud service
consumer is unaware it is interacting with different implementations
of Cloud Service A located in different geographical regions.
There are many different types of cloud-based technology
architectures that can be created to support this benefit, including
the option for one cloud to leverage IT resources in another cloud.
121. Increased Availability and
Reliability
1. The cloud service consumer invokes capability1 of Service A. Service A is
a cloud-based service that is physically implemented on a server residing
in a specific geographic region (Region 1).
2. Cloud Service A replies with the expected response message.
3. The next time the cloud service consumer attempts to invoke the same
capability of the same service, the cloud determines that the previous
implementation (the one residing in Region 1) is currently unavailable. The
request message is therefore automatically routed to a different
implementation of Cloud Service A, which resides in a different
geographic region (Region 2).
4. Cloud Service A replies with the expected response message.
123. Challenges of Cloud Computing
The following are common cloud computing adoption challenges:
• Increased Security Vulnerabilities
• Reduced Operational Governance Control
• Limited Portability Between Cloud Providers
• Multi-Regional Compliance and Legal Issues
Note that all of these challenges pertain primarily to cloud consumers
that use IT resources located in public clouds (as explained in the Cloud
Deployment Models section).
124. Increased Security Vulnerabilities
The remote usage of IT resources requires an expansion of trust
boundaries by the cloud consumer to include an external cloud.
Unless the cloud consumer and cloud provider support the same or
compatible security technologies, it can be difficult to establish a
security architecture that spans the trust boundary without
introducing vulnerabilities.
Furthermore, because cloud-based IT resources can be shared,
there can be overlapping trust boundaries from different cloud
consumers (as illustrated on the following page).
125. Increased Security Vulnerabilities
In the example on the following page, two organizations accessing
the same cloud service are required to extend their respective trust
boundaries to the cloud, resulting in overlapping trust boundaries. It
can be difficult for a cloud provider to offer security technologies
that accommodate the security requirements of both cloud service
consumers.
Furthermore, the fact that trust boundaries overlap can lead to
opportunities for an attacker to attack IT resources shared by
multiple cloud consumers.
127. Reduced Operational
Governance Control
When forming dependencies on externally cloud-hosted IT
resources, cloud consumers are almost always given a lower level of
governance control when compared to on-premise IT resources.
This reduced level of control can introduce risks pertaining to how a
cloud is operated by the cloud provider, as well as external
connections between the cloud consumer and the cloud.
Cloud consumers are often required to rely on Service Level
Agreements (SLAs) and other warranties made by the cloud
provider.
128. Reduced Operational
Governance Control
This challenge can relate to the organization providing a cloud or
the external connections required to communicate with the cloud.
For example:
• An unreliable cloud provider may not maintain guarantees it makes in
the SLAs published for its cloud services. This can jeopardize the quality
of cloud consumer solutions that rely on these cloud services.
• The geographic distance between the cloud consumer and cloud
provider can require additional network hops that introduce fluctuating
latency and potential bandwidth constraints. This can also jeopardize
the quality of cloud consumer solutions that rely on cloud services.
129. Reduced Operational
Governance Control
Legal contracts, combined with SLAs, technology inspections, and
monitoring can mitigate these risks.
However, with public clouds, there is always a risk that the cloud
provider will be acquired or may go out of business, potentially
resulting in an inability to fulfill legal obligations.
This, combined with the Limited Portability challenge (explained
shortly), can have significantly restrictive impacts on the cloud
consumer.
Note that SLAs are explained in detail in the Service Level
Agreements section.
130. Example of an Unreliable Cloud
Provider
Because a cloud provider has
more governance control than
the cloud consumer, it may be
able to make changes to IT
resources without the cloud
consumer's permission.
The diagrams on the right
depict an example whereby an
irresponsible cloud provider
performs a non-backwards-
compatible upgrade of the
messaging technology.
The details for each step are
listed on the next page.
131. Reduced Operational
Governance Control
1. The cloud service consumer accesses cloud services (not shown)
hosted on a virtual server. Both the cloud service consumer and the
cloud services are designed to support the exchange of messages
based on the SOAP 1.1 industry standard.
2. Without informing the cloud consumer, the cloud provider upgrades
the virtual machine so that it can now only support messages based
on the SOAP 1.2 industry standard. (The tact that this upgrade is non-
backwards compatible to SOAP 1.1 may be accidental.)
3. The cloud service consumer is no longer able to access cloud services
on the virtual server using SOAP 1.1 compliant messages.
Note that different cloud delivery models will offer different levels of
operational and governance control. This example is specific to the SaaS
delivery model, as explained in the Cloud Delivery Models section.
132. Reduced Operational
Governance Control
Example of an Unreliable Network
The following diagram explains that
despite the cloud consumer and cloud
provider each having reliable networks,
the network connection between their
respective environments can still
jeopardize communication.
133. Reduced Operational
Governance Control
Example of an Unreliable Network (continued)
A cloud consumer has a local area network with a robust bandwidth of 1 Gbps.
The cloud provider also has a robust local area network with a bandwidth of 1 Gbps.
The network connecting the cloud consumer and cloud provider has a bandwidth of
100mbps.
The connection from the cloud consumer to the cloud provider over the Internet is
also subjected to variable speeds and network hops that further limit throughput.
The total throughput for communications between cloud consumer and cloud
provider is limited to a bandwidth of 100mbps, plus additional fluctuations.
134. Limited Portability Between
Cloud Providers
Due to a lack of established industry standards within the cloud computing
industry, individual public clouds are proprietary to various extents.
For cloud consumers that have custom-built solutions with dependencies
on these proprietary environments, it can be challenging to move from
one cloud provider to another.
This challenge can be mitigated if cloud consumers can build solutions
based on industry standards and if cloud providers support these industry
standards.
Note that this challenge is especially relevant for PaaS and laaS delivery
models.
135. As an example, a
cloud consumer
may be unable to
migrate an
application from
Cloud A to Cloud B
because the cloud
provider of Cloud B
does not support the
same security
technologies as
Cloud A.
136. Multi-Regional Compliance
and Legal issues
Cloud consumers will often not have information regarding the physical
location of the IT resources provided by third party cloud providers.
Depending on the nature of the cloud consumer’s business, there may be
industry or government regulations and policies that impose specific legal
requirements.
For example, the Payment Card Industry Data Security Standard (PCI DSS)
requires that cardholder data be stored in separated network segments.
Cloud consumers unaware of the location of data or IT resources hosted by
cloud providers may not be able to comply with such regulations and
policies.
137. Multi-Regional Compliance
and Legal issues
Another regional legal issue that can pose problems is the disclosure of
cloud hosted data.
A cloud consumer may be unaware that a cloud provider is physically
locating the cloud consumer's storage device in a country where the risk of
data being disclosed is higher than in other countries.
For example, data stored in the United States by a EU- based cloud
consumer can be easier accessed than data stored in EU countries due to
the enactment of the USA PATRIOT act.
Reputable cloud providers can generally provide guarantees that these
types of compliance and legal concerns are addressed.
139. Overview
Metrics are measured statistics collected for analysis purposes.
This section focuses on the following core metrics used to evaluate
the estimated costs and business value of leasing cloud-based IT
resources when compared to the purchase of on-premise IT
resources.
• Up-front Costs
• On-going Costs
The following additional cost metrics are also described:
• Cost of Capital
• Sunk Costs
• Integration Costs
• Locked-in Costs
140. Up-front Costs
Up-front costs represent the initial investment required by the
organization to fund the IT resources it requires.
Up-front costs for the purchase and deployment of on-premise IT
resources tend to be high.
Examples of up-front costs for on-premise environments can include
hardware, software and the labor required for deployment.
Up-front costs for the leasing of cloud-based IT resources tend to be low.
Examples of up-front costs for cloud-based environments can include
the labor costs required to assess and set up a cloud environment.
141. On going- Costs
On-going costs represent the expenses required by the organization to run
and maintain IT resources it uses.
On-going costs for the operation of on-premise IT resources can vary.
Examples of on-going costs for on-premise environments can include
licensing fees, electricity, insurance, and labor.
On-going costs for the operation of cloud-based IT resources can also vary,
but often exceed the on-going costs of on-premise IT resources (especially
over a longer period of time).
Examples of on-going costs for cloud-based environments include virtual
hardware leasing fees, bandwidth usage fees, licensing fees and labor.
142. Up-front Costs and On-going Costs
The following is an example metrics analysis:
Let’s assume an organization requires three new physical servers.
The purchase price of one server is $7,000 and the monthly lease cost of
the same server from a cloud provider is $1,000.
The organization chooses to calculate the up-front and on-going costs
for the usage of the servers over a period of three years.
The table on the next page provides a sample comparison of up-front
and on-going costs for on-premise and cloud-based environments.
143. Up-front Costs and On-going Costs
Over a period of three years, the on-
premise environment would cost the
organization $163,100 based on the
following calculation:
$33,500 up-front cost +
($3,600 on-going costs x 36 months)
Over a period of three years, the cloud-
based environment would cost the
organization $158,500 based on the
following calculation:
$100 up-front cost +
($4,400 on-going costs x 36 months)
144. Up-front Costs and On-going Costs
The preceding analysis assumes the three servers will be fully used over
the three-year period.
However, in most cases, the usage requirements of an organization will
fluctuate.
This is where the elasticity characteristic of cloud environments can
have a significant impact on on-going usage costs.
Let’s assume that, over the three-year period, the organization will
actually require a maximum of 3 servers, a minimum of 1 server and 2
servers on average.
The table on the next page shows the adjusted costs.
146. Up-front Costs and On-going Costs
The on-premise costs remain unchanged.
The cloud-based up-front cost has been increased to reflect the
additional labor required to set-up the scalability parameters for the
use of one to three servers.
The cloud-based on-going cost has been decreased to represent
the fact that, on average, less IT resources will be used.
The result is a decrease of the cloud-based costs to a total of
$124,900 over the three year period.
147. Additional Metrics
The preceding analysis provides a basic insight into the primary cost
metrics for evaluating the usage cloud-based IT resources.
However, this type of analysis can be more complex, as there are
additional metrics that can be taken into account, depending on a
given organization's unique requirements and circumstances.
The next pages describe the following additional types of metrics:
• Cost of Capital
• Sunk Costs
• Integration Costs
• Locked-in Costs
148. Cost of Capital
The cost of capital is a value that represents the cost incurred by
raising required funds.
For example, it will generally be more expensive to raise an initial
investment of $150,000 than it will be to raise this amount over a
period of three years.
The relevancy of this cost depends on how the organization goes
about raising the funds it requires.
If the cost of capital for an initial investment is high, then it further
helps justify the leasing of cloud-based IT resources.
149. Sunk Costs
An organization will often have existing IT resources that are already
paid for and operational.
The prior investment that has been made in these on-premise IT
resources is referred to as sunk costs.
When comparing cloud-based IT resources to on-premise IT
resources with sunk costs, the up-front costs for on-premise IT
resources is significantly lower.
It can therefore be more difficult to justify the leasing of cloud-
based IT resources as an alternative.
150. Integration Costs
Integration testing is a form of testing required to measure the effort
required to make IT resources compatible and interoperable within a
new environment, such as a new cloud platform.
Depending on the cloud deployment model and cloud delivery model
being considered by an organization, there may be the need to further
allocate funds to carry out integration testing and additional labor
related to enable interoperability between cloud service consumers
and cloud services.
These expenses are referred to as integration costs.
High integration costs imposed by cloud providers can make the option
of leasing cloud-based IT resources less appealing.
151. Locked-in Costs
As explained earlier in the Challenges of Cloud Computing section 24,
cloud environments can impose portability limitations.
When performing a metrics analysis over a longer period of time, it may
be necessary to take into consideration the possibility of having to
move from one cloud provider to another.
Due to the fact that cloud service consumers can become dependent
on proprietary characteristics of a cloud environment, there are locked-
in costs (primarily related to labor) associated with this type of move.
Locked-in costs can further decrease the long-term business value of
leasing cloud-based IT resources.
153. Service Level Agreements
A Service Level Agreement (SLA) is a document that describes
quality-of-service features, behaviors, and limitations of a service.
An SLA can be considered a human-readable part of a service
contract that extends the technical service contract.
Because cloud environments intentionally hide back-end
implementation details about cloud services, the guarantees
expressed in SLAs become very important to cloud consumers.
154. Service Level Agreements
A typical SLA document for a cloud service will cover three specific
quality-of-service characteristics:
• availability
• reliability
• performance
The following sections describe each of these characteristics
separately.
155. Service Level Agreement:
Availability
The availability of an IT resource is the probability that it will be
accessible.
The probability value is generally expressed with a percentage
representing the amount of time that the IT resource is accessible
during a given period.
The percentage is calculated as follows:
1. Divide the amount of hours the IT resource was unavailable (within a
measured period) by the total amount of hours within the measured
period.
2. Multiply the value by 100.
3. Deduct the value from 100.
156. Service Level Agreements:
Availability
For example, let's take a Web service that was unavailable for 18
hours over the course of a year (24 x 365 = 8,760 hours):
• 18 hours / 8,760 hours = 0.002
• 0.002 x 100 = 0.2
• 100-0.2 = 99.8
The availability rating of the Web service for the measured period is
99.8%.
157. Service Level Agreements:
Availability
The availability value guaranteed in the SLA is based on assumptions
regarding future downtimes.
Future downtimes are estimated by assigning the event that causes a
downtime a probability for its occurrence and the time it would take to
bring up the IT resource again.
The percentage is calculated as follows:
1. Multiply the probability of downtime by the actual estimated downtime.
2. Divide the value by a measured period of time.
3. Multiply the value by 100.
4. Deduct the value from a 100.
158. Service Level Agreements:
Availability
For example, a Web service may rely on a network that has a 20%
probability of crashing over the course of a year, plus it is further
estimated that it would take 12 hours to recover:
0.2 x 12 hours = 2.4
2.4 / 8,670 = 0.00028
0.00028x100 = 0.028
100 - 0.028 = 99.97 (rounded to two decimals)
The availability rating of the network for the measured period is
99.97%.
159. Service Level Agreements:
Reliability
Reliability represents the probability that an IT resource performs its
intended functions without failure under pre-defined conditions.
A common formula tor calculating the reliability rating of an IT
resource, is to take the number of successful executions of its
function(s) and divide that value by the number of attempts made to
execute those function(s).
Multiple the result by 100 to determine the reliability percentage.
160. Service Level Agreements:
Reliability
For example, let's take a Web service that received 3,000 invocation
attempts over a given period, but only executed 2,892 of those
attempts successfully:
• 2,892 /3,000 = 0.964
• 0.964 x100 = 96.4
The reliability rating of the Web service during the measured period is
96.4%.
Reliability is closely related to availability because, in order to be
reliable, the IT resource needs to be available.
161. Service Level Agreements:
Performance
The maximum performance of an IT resource represents the capacity
up to which the IT resource is able to perform its functions.
The determination of this capacity (the performance rating) of a given
IT resource depends on its type and purpose.
For example, a Web service's performance rating could be specified in
calls per seconds and the response time for each call.
A development environment, on the other hand, may measure
capacity in the maximum number of concurrent users that can be
supported.
162. Service Level Management
Agreements Types
There are three types of SLM agremeents:
Service Level Agreement (SLA)
Operational Level Agreement (OLA)
Underpinning Contracts (UC)
163. Service Level Management
Agreements Types
OLA : An Agreement between an IT Service Provider and another part
of the same Organization. An OLA supports the IT Service Provider's
delivery of IT Services to Customers. The OLA defines the goods or
Services to be provided and the responsibilities of both parties.
For example there could be an OLA between the:
IT Service Provider and a procurement department to obtain hardware in
agreed times
Service Desk and a Support Group to provide Incident Resolution in agreed
times.
164. Service Level Management
Agreements Types
UC : A Contract between an IT Service Provider and a Third Party. The
Third Party provides goods or Services that support delivery of an IT
Service to a Customer.
The Underpinning Contract defines targets and responsibilities tat are
required to meet agreed Service Level Targets in an SLA.
176. “In 1999: 38M people had
broadband internet
Today: 1.3B people have it on their
mobile phones”
Ctrlaltdeletebook.com
177. The world is changing has changed
MOBILITY:
1,3 billion world’s
mobile worker
population will be
reached by 2015
SOCIAL:
65% of companies
are deploying at
least one social
software tool
CLOUD:
70% of business are
either using or
investigating cloud
computing solutions
ANALYTICS:
Big Data market is
growing 40% every
year to reach $17
billion by 2015
178. IDC Prediction
3rd Platform will dominate
growth
3rd Platform will
cannibalize 2nd Platform
Value migrating within
3rd Platform
179. The CLOUD takes shapes
The key objectives behind your approach to cloud adoption?
“Business executives are starting to appreciate the potential
transformative value of cloud”