Cloud Computing Architecture

1. INTRODUCTION TO
INTRODUCTION TO
CLOUD COMPUTING
CLOUD COMPUTING
Understand Cloud Computing Architecture
Understand cloud model
Upon completion of this
course, students should be
able:
C
L
O
1
Apply the core concepts
of distributed systems
underlying cloud
computing systems and
architecture.
(C3, PLO1)
C
L
O
2
Use the concepts of
distributed systems to
analyse, design and
implement cloud
computing systems by
using an appropriate
software. (C3, P3, A3,
PLO1, PLO2, PLO4)
C
L
O
3
Deploy new cloud
applications. (P4, A4,
PLO2, PLO4)

2. What
What
you will
you will
learn?
learn?
2.2 Understand Cloud Models:
2.2.1 Explain Cloud Service Models:
a. Infrastructure as a Services (Iaas)
b. Platform as a Services (Paas)
c. Software as a Services (Saas)
2.2.2 Explain Deployment Models
a. Public Cloud
b. Private Cloud
c. Hybrid Cloud
d. Community Cloud

3. Cloud
Computing
Presentation Title
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4. Cloud
Cloud
Computing
Computing
Service
Service
Model
Model
Cloud computing offered different services based on
three models:
Infrastructure as a Services (Iaas)
Platform as a Services (Paas)
Software as a Services (Saas)

5. About SAAS
About SAAS
• On-demand service
• Pay per use of application software to users
• Independent platform
• Don’t need to install the software on your
PC
• Runs a single instance of the software
• Available for multiple end users
• Cloud computing cheap
• Computing resources managed by vendor
• Accessible via a web browser or lightweight
client application
• User of SaaS : End customers

6. About SAAS
About SAAS
SaaS provides the complete infrastructure, software,
and solution stack as the service offering.
A good way to think about SaaS is that it is the cloud-
based equivalent of shrink-wrapped software.
SaaS applications come in all shapes and sizes, and
include custom software such as billing and invoicing
systems:
•Customer Relationship Management (CRM)
applications,
•Help Desk applications,
•Human Resource (HR) solutions,
•Myriad online versions of familiar applications

7. Characterist
Characterist
ic of SAAS
ic of SAAS
1. The software is available over the Internet globally through a browser on
demand.
2. The typical license is subscription-based or usage-based and is billed on a
recurring basis.
3. The software and the service are monitored and maintained by the vendor,
regardless of where all the different software components are running.
4. Reduced distribution and maintenance costs and minimal end-user system costs
generally make SaaS applications cheaper to use than their shrink-wrapped
versions.
5. Such applications feature automated upgrades, updates, and patch management
and much faster rollout of changes.
6. SaaS applications often have a much lower barrier to entry than their locally
installed competitors, a known recurring cost, and they scale on demand (a
property of cloud computing in general).
7. All users have the same version of the software so each user’s software is
compatible with another’s.
8. SaaS supports multiple users and provides a shared data model through a single-
instance, multi-tenancy model. The alternative of software virtualization of
individual instances also exists, but is less common.

8. Characterist
Characterist
ic of SAAS
ic of SAAS
Diagram shows the SaaS implementation based on
SOA

9. Popular
SaaS
Providers
Presentation Title
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10. SAAS : PROS
SAAS : PROS
 Universally accessible from any platform
 No need to commute, you can work from
any place
 Excellent for collaborative working
 Vendor provides modest software tools
 Allows for multi-tenancy

11. SAAS : CONS
SAAS : CONS
 Portability & Browser Issues
 Internet performance may dictate overall
performance
 Compliance restrictions

12. About of
About of
PAAS
PAAS
 This service is made up of a programming language
execution environment, an operating system, a
web server & a database.
 Encapsulate the environment where users can
build, compile & run their programs without
worrying of the underlying infrastructure.
 In this model, you manage data & application
resources, all other resources are managed by the
vendor.
 User of PaaS : Developers

13. About of
About of
PAAS
PAAS
 The Platform as a Service model describes a
software environment in which a developer can
create customized solutions within the context of
the development tools that the platform provides.
 Platforms can be based on specific types of
development languages, application frameworks,
or other constructs.
 PaaS systems must offer a way to create user
interfaces, and thus support standards such as
HTLM, JavaScript, or other rich media
technologies.
 App Engine of Google and Force.com are
examples of PaaS offering vendors. Developer may
log on to these websites and use the built-in API to
create web-based applications

14. About of
About of
PAAS
PAAS
 Platform-as-a-Service offers the runtime
environment for applications.
 It also offers development and deployment
tools required to develop applications.
 PaaS has a feature of point-and-click tools
that enables non-developers to create web
applications.

15. PaaS
Products &
Services
Presentation Title
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16. PAAS : PROS
PAAS : PROS
 Cost effective rapid development (Its
Scalable)
 Faster market for developers
 Easy Deployment of web applications
 Private or public deployment is possible

17. PAAS : CONS
PAAS : CONS
 Developers are limited to the providers
languages & tools
 Migration Issues – Such as the risk of
vendor lock in

18. About of
About of
IAAS
IAAS
 This services offers the computing architecture
& infrastructures, all computing resources but
in a virtual environment so that multiple users
can access them.
 Resources include : data storage,
virtualization, servers & networking. Most
vendors are responsible for managing these
resources.
 User will be responsible for handling other
resources such as applications, data, runtime
& middleware.
 User of IaaS : Sys Admins

19. Characterist
Characterist
ic of IAAS
ic of IAAS
Here are the characteristics of IaaS service model:
Virtual machines with pre-installed software.
Virtual machines with pre-installed operating systems
such as Windows, Linux, and Solaris.
On-demand availability of resources.
Allows to store copies of particular data at different
locations.
The computing resources can be easily scaled up and
down.

20. Characterist
Characterist
ic of IAAS
ic of IAAS
All of the resources are made available to end user
via server virtualization. Moreover, these resources
are accessed by the customers as if they own them.

21. IaaS
Products &
Services
Presentation Title
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22. IAAS : PROS
IAAS : PROS
 The cloud provides the infrastructure
 Enhanced scalability – Dynamic workloads
are supported
 IaaS is flexible

23. IAAS : CONS
IAAS : CONS
 Security issues
 Network & Service Delays

24. Service
Service
Delivery
Delivery
Model
Model
Products and companies shown for illustrative purposes only and should not be
construed as an endorsement

25. Cloud
Cloud
Service
Service
Model
Model
Cloud
Delivery
Model
Typical Level of
Control Granted to
Cloud Consumer
Typical Functionality Made Available to Cloud Consumer
SaaS
Usage and usage-
related configuration
Access to front-end user-interface
PaaS Limited administrative
Moderate level of administrative control over IT resources
relevant to cloud consumer’s usage of platform
IaaS Full administrative
Full access to virtualized infrastructure-related IT resources
and possibly to underlying physical IT resources
Cloud
Delivery
Model
Common Cloud
Consumer
Activities
Common Cloud Provider Activities
SaaS
Uses and
configures cloud
service
 Implements, manages and maintains cloud service
 Monitors usage by cloud consumers
PaaS
Develops, tests,
deploys and
manages cloud
services and cloud-
based solutions
Pre-configures platform and provisions underlying
infrastructure, middleware and other needed IT resources as
necessary
IaaS
Sets up and
configures bare
infrastructure, and
installs, manages,
and monitors any
needed software
 Provisions and manages the physical processing, storage,
networking and hosting required
 Monitors usage by cloud consumers
Reference: http://home.sogang.ac.kr/sites/gsinfotech/study/Lists/b15/Attachments/2/Cloud%20Computing%20Lecture%20Note%202%20-
%20Fundamental%20Concepts%20and%20Models.pptx

26. Service
Service
Model
Model
Architecture
Architecture
Cloud Infrastructure
IaaS
PaaS
SaaS
Infrastructure as a Service (IaaS)
Architectures
Platform as a Service (PaaS)
Architectures
Software as a Service
(SaaS)
Architectures
Cloud Infrastructure
SaaS
Cloud Infrastructure
PaaS
SaaS
Cloud Infrastructure
IaaS
PaaS
Cloud Infrastructure
PaaS
Cloud Infrastructure
IaaS

27. Q & A
Thank You
Thank You
Reference: Barrie Sosinsky (2011), “Cloud Computing Bible”, page 46 – 64.