Get an insight of cloud and how to develop its features

1. SEMINAR REPORT
on
Cloud Computing
As a partial fulfillment of B.Tech degree
in Information Technology
By
Ashutosh Anshu (14150014)
Under the guidance of
Dr. Daleesha M Vishwanathan
Division of Information Technology
School Of Engineering, CUSAT
2017
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2. ACKNOWLEDGEMENT
It is my proud privilege and duty to acknowledge the kind of help and guid-
ance received from my seminar guide Dr. Daleesha M Vishwanathan. It
would not have been possible to present the seminar and report in this form
without her valuable help, cooperation and guidance.
I am extremely grateful to her for the guidance and encouragement and for
providing me with best facilities and atmosphere for the creative work. I would
also like to thank my friends and also several people in presentation of the sem-
inar and preparation of this report.
Thanking you,
Ashutosh Anshu
2

3. ABSTRACT
Cloud Computing is a virtualized compute power and storage delivered via
platform-agnostic infrastructures of abstracted hardware and software accessed
over the internet. These shared on-demand IT resources are created and dis-
posed off efficiently and are dynamically scalable through a variety of program-
matic interfaces and are billed variably based on measurable usage.
Cloud Computing is a general term for anything that involves delivering
hosted services over the internet. These services are broadly classified into three
categories: Infrastructure as a Service (IaaS), Software as a Service (SaaS) and
Platform as a Service (PaaS). The 5-4-3 of Cloud Computing refers to 5 chara
teristics, 4 deployment models and 3 service models.
3

4. Contents
1 INTRODUCTION 6
2 5 CHARACTERISTIICS OF CLOUD COMPUTING 7
2.1 On-Demand Self Service . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Broad Network Access . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 Resource Pooling . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.4 Rapid Elasticity . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.5 Measured Service . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3 4 DEPLOYMENT MODELS 10
3.1 Private Cloud . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2 Public Cloud . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3 Hybrid Cloud . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.4 Community Cloud . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4 SERVICE MODELS 14
4.1 Software as a Service . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2 Platform as a Service . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.3 Infrastructure as a Service . . . . . . . . . . . . . . . . . . . . . . 15
4.3.1 Storage as a Service . . . . . . . . . . . . . . . . . . . . . 16
4.3.2 Containers as a Service . . . . . . . . . . . . . . . . . . . 17
4.3.3 Network as a Service . . . . . . . . . . . . . . . . . . . . . 18
4.3.4 Implementing IaaS on a small scale . . . . . . . . . . . . . 19
5 Comparison between the three service models 20
6 CHALLENGES TO CLOUD COMPUTING 21
6.1 Security and Privacy . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.2 Interoperability and Portability . . . . . . . . . . . . . . . . . . . 21
6.3 Reliability and Availability . . . . . . . . . . . . . . . . . . . . . 21
6.4 Performance and Bandwidth Cost . . . . . . . . . . . . . . . . . 21
7 CONCLUSION 22
8 REFERENCES 23
4

5. List of Figures
1 Real world scenario . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Openstack- a private cloud platform . . . . . . . . . . . . . . . . 10
3 The largest public cloud provider . . . . . . . . . . . . . . . . . . 11
4 Rackspace- a hybrid cloud provider . . . . . . . . . . . . . . . . . 12
5 Salesforce- a community cloud provider . . . . . . . . . . . . . . 13
6 Architecture for SaaS . . . . . . . . . . . . . . . . . . . . . . . . 14
7 Amazon Kinesis- a platform for Big Data applications . . . . . . 15
8 Object Storage Architecture . . . . . . . . . . . . . . . . . . . . . 16
9 Block Storage Architecture . . . . . . . . . . . . . . . . . . . . . 17
10 Difference between a Container and a Virtual Machine . . . . . . 17
11 Docker is the most optimized and largest used conatinerization
tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
12 AWS Network Load Balancer . . . . . . . . . . . . . . . . . . . . 19
13 IaaS Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
14 Comparison between all the service models . . . . . . . . . . . . 20
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6. Cloud Computing
CHAPTER 1
1 INTRODUCTION
Cloud computing is a model for enabling ubiquitous, convenient, on-demand network
access to a shared pool of configurable computing resources (e.g., networks, servers,
storage, applications, and services) that can be rapidly provisioned and released with
minimal management effort or service provider interaction. This cloud model is com-
posed of five essential characteristics, three service models, and four deployment mod-
els.
The evolution of cloud computing over the past few years is potentially one of the ma-
jor advances in the history of computing. However, if cloud computing is to achieve its
potential, there needs to be a clear understanding of the various issues involved, both
from the perspectives of the providers and the consumers of the technology. While a
lot of research is currently taking place in the technology itself, there is an equally ur-
gent need for understanding the business-related issues surrounding cloud computing.
Cloud computing is a technology towards which every enterprise (almost) is migrating
and spend on services provided by the cloud provider rather than spending huge funds
and time on working for getting the correct infrastructure for their firm. For example,
if there is a finance enterprise (company) whose main objective is to handle finance
issues of public as well as public sectors, the company would always want to invest
their man-power, time and cost on providing the core finance services for the company
has been formed rather than spending its resources on getting computer hardwares
and softwares for storing and managing data.
Data is the most important commodity for any enterprise. For storing their data
can not ignore the inevitable need for computer resource in abundance. The problem
for such companies is the same as discussed above. They would always want to utilize
their resources on their core services rather than on building perfect infrastructure for
data storage and management.
Figure 1: Real world scenario
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7. 5 Characteristics
CHAPTER 2
2 5 CHARACTERISTIICS OF CLOUD COM-
PUTING
When we say 5-4-3 of Cloud Computing, we mean 5 characteristics, 4 deployment
models and 3 service models.
These 5 characteristics include:-
2.1 On-Demand Self Service
On-demand self-service, as defined by the National Institute of Standards and Tech-
nology, is the process through which a consumer (or any user for our purposes here)
can unilaterally provision computing capabilities, such as server time and network
storage, as needed automatically without requiring human interaction with each ser-
vice provider. According to many critics, this feature of cloud computing is essential
for the proper advancement of this technology. This process may be viewed as an
evolution of software as a service. Although it is more connected to software utilities,
this type of on-demand service is also very much linked to the two other features of
cloud computing. When infrastructure as a service, software as a service and platform
as a service are viewed as interlinked, one can easily see how these features have helped
to create solutions such as on-demand self-service and on-demand computing.
On-demand self-service is a characteristic which is essential for the proper oper-
ation of cloud computing services. This feature allows cloud computing users to run
their own sessions, without interaction with service providers or other parties. A con-
sumer can provision computing capabilities such as server time and network storage, as
needed automatically, without any requirement of human interaction with each service
provider.
With subsequent rise and enhancement in technology, certain features (like AWS
Lambda) have improvised self configuration and made the resource configuration au-
tomated. Lambda can be used to scale-in or scale-out a set of resources based on the
computing power and requirement of the consumer/client.
2.2 Broad Network Access
Cloud computing separates computing capabilities from their consumers, so that they
dont have to maintain the capabilities themselves. A consequence of this is that the
computing capabilities are located elsewhere, and must be accessed over a network.
Broad network access refers to resources hosted in a private cloud network (operated
within a company’s firewall) that are available for access from a wide range of devices,
such as tablets, PCs, Macs and smart phones. These resources are also accessible from
a wide range of locations that offer online access. Companies that have broad network
access within a cloud network need to deal with certain security issues that arise. It’s
a debated topic because it touches at the heart of the difference between private and
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8. 5 Characteristics
public cloud computing. Oftentimes, companies choose private cloud service because
they are concerned about the potential for information leaks through the gaps left
open to outside networks in a public cloud.
Broad network access is something that, in a way, goes against the idea of a private
cloud. However, as more employees use smart phones, tablets and other devices with
online connectivity, they want to access company resources and continue to work from
these devices. It is possible to give access to various devices from a private cloud.
However, although broad network access may not be deployed by many companies in
a purely private cloud model, it is becoming more common in hybrid cloud settings.
2.3 Resource Pooling
Resource pooling is an IT term used in cloud computing environments to describe
a situation in which providers serve multiple clients, customers or ”tenants” with
provisional and scalable services. These services can be adjusted to suit each client’s
needs without any changes being apparent to the client or end user. The idea behind
resource pooling is that through modern scalable systems involved in cloud computing
and software as a service (SaaS), providers can create a sense of infinite or immediately
available resources by controlling resource adjustments at a meta level. This allows
customers to change their levels of service at will without being subject to any of the
limitations of physical or virtual resources.
The kinds of services that can apply to a resource pooling strategy include data
storage services, processing services and bandwidth provided services. Other related
terms include rapid elasticity, which also involves the dynamic provisioning of ser-
vices, and on-demand self-service, where customers could change their levels of service
without actually contacting a service provider. All of this automated service provi-
sioning is a lot like other kinds of business process automation, which replaced more
traditional, labor-intensive strategies with new innovations that rely on increasingly
powerful virtual networks and data handling resources. In these cases, the goal is to
separate the client experience from the actual administration of assets, so that the
process of delivery is opaque and the services seem to be automatically and infinitely
available.
2.4 Rapid Elasticity
In cloud computing, elasticity is defined as ”the degree to which a system is able
to adapt to workload changes by provisioning and de-provisioning resources in an
autonomic manner, such that at each point in time the available resources match the
current demand as closely as possible”. Elasticity is a defining characteristic that
differentiates cloud computing from previously proposed computing paradigms, such
as grid computing. The dynamic adaptation of capacity, e.g., by altering the use of
computing resources, to meet a varying workload is called ”elastic computing”.
Elasticity aims at matching the amount of resource allocated to a service with the
amount of resource it actually requires, avoiding over- or under-provisioning. Over-
provisioning, i.e., allocating more resources than required, should be avoided as the ser-
vice provider often has to pay for the resources that are allocated to the service. For ex-
ample, an Amazon EC2 M4 extra-large instance costs US0.239/hour.Ifaserviceisallocatedtwovirtualmachines, insteado
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9. 5 Characteristics
every year. Hence, the service provider’s expenses are higher than optimal and the
profit is reduced.
Under-provisioning, i.e., allocating fewer resources than required, must be avoided,
otherwise the service cannot serve its users with a good service. In the above example,
under-provisioning the website may make it seem slow or unreachable. Web users
eventually give up on accessing it, thus, the service provider loses customers. On the
long term, the provider’s income will decrease, which also reduces the profit
2.5 Measured Service
Measured service is a term that IT professionals apply to cloud computing. This is
a reference to services where the cloud provider measures or monitors the provision
of services for various reasons, including billing, effective use of resources, or overall
predictive planning.
The idea of measured service is one of five components of a definition of cloud
computing supported by the National Institute of Standards and Technology or NIST.
These five principles support a higher-level definition of cloud services and describe how
they are typically designed. Other aspects of this definition include the terms ’rapid
elasticity and ’resource pooling, which cover different kinds of resource allocation.
Theres also ’on-demand self-service, which refers to more automated service changes,
and ’broad network access, which refers to the overall footprint and capabilities of
cloud systems.
The NIST talks about measured service as a setup where cloud systems may con-
trol a user or tenants use of resources by leveraging a metering capability somewhere in
the system. The general idea is that in automated remote services, these measurement
tools will provide both the customer and the provider with an account of what has
been used. In more traditional systems, items like invoices and service change agree-
ments would fill these same roles. Measured service ensures that even when there is
no specific interaction for a service change, that service change is still noted so that it
can be negotiated or dealt with a later date, for instance, in a billing cycle.
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10. 4 Deployment Models
CHAPTER 3
3 4 DEPLOYMENT MODELS
Four deployment models are:-
3.1 Private Cloud
Private cloud is a type of cloud computing that delivers similar advantages to public
cloud, including scalability and self-service, but through a proprietary architecture.
Unlike public clouds, which deliver services to multiple organizations, a private cloud
is dedicated to a single organization.
As a result, private cloud is best for businesses with dynamic or unpredictable
computing needs that require direct control over their environments.
Public and private cloud deployment models differ. Public clouds, such as those
from Amazon Web Services or Google Compute Engine, share a computing infras-
tructure across different users, business units or businesses. However, these shared
computing environments aren’t suitable for all businesses, such as those with mission-
critical workloads, security concerns, uptime requirements or management demands.
Instead, these businesses can provision a portion of their existing data center as an
on-premises – or private – cloud.
A private cloud provides the same basic benefits of public cloud. These include
self-service and scalability; multi-tenancy; the ability to provision machines; changing
computing resources on-demand; and creating multiple machines for complex comput-
ing jobs, such as big data. Charge back tools track computing usage, and business
units pay only for the resources they use.
Figure 2: Openstack- a private cloud platform
3.2 Public Cloud
A public cloud is one based on the standard cloud computing model, in which a service
provider makes resources, such as virtual machines (VMs), applications or storage,
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11. 4 Deployment Models
available to the general public over the internet. Public cloud services may be free or
offered on a pay-per-usage model.
Public cloud is a fully virtualized environment. In addition, providers have a multi-
tenant architecture that enables users or tenants, to share computing resources. Each
tenant’s data in the public cloud, however, remains isolated from other tenants. Public
cloud also relies on high-bandwidth network connectivity to rapidly transmit data.
Public cloud storage is typically redundant, using multiple data centers and careful
replication of file versions. This characteristic has given it a reputation for resiliency.
The main benefits of using a public cloud service are: it reduces the need for orga-
nizations to invest in and maintain their own on-premises IT resources; it enables
scalability to meet workload and user demands; and there are fewer wasted resources
because customers only pay for the resources they use.
Figure 3: The largest public cloud provider
3.3 Hybrid Cloud
Hybrid cloud is a cloud computing environment which uses a mix of on-premises,
private cloud and third-party, public cloud services with orchestration between the
two platforms. By allowing workloads to move between private and public clouds as
computing needs and costs change, hybrid cloud gives businesses greater flexibility
and more data deployment options.
For example, an enterprise can deploy an on-premises private cloud to host sensi-
tive or critical workloads, but use a third-party public cloud provider, such as Google
Compute Engine, to host less-critical resources, such as test and development work-
loads. To hold customer-facing archival and backup data, a hybrid cloud could also
use Amazon Simple Storage Service (Amazon S3). A software layer, such as Eucalyp-
tus, can facilitate private cloud connections to public clouds, such as Amazon Web
Services (AWS).
Hybrid cloud is particularly valuable for dynamic or highly changeable workloads.
For example, a transactional order entry system that experiences significant demand
spikes around the holiday season is a good hybrid cloud candidate. The application
could run in private cloud, but use cloud bursting to access additional computing
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12. 4 Deployment Models
resources from a public cloud when computing demands spike. To connect private and
public cloud resources, this model requires a hybrid cloud environment.
Another hybrid cloud use case is big data processing. A company, for example,
could use hybrid cloud storage to retain its accumulated business, sales, test and other
data, and then run analytical queries in the public cloud, which can scale to support
demanding distributed computing tasks.
Public cloud’s flexibility and scalability eliminates the need for a company to make
massive capital expenditures to accommodate short-term spikes in demand. The pub-
lic cloud provider supplies compute resources, and the company only pays for the
resources it consumes.
Despite its benefits, hybrid cloud can present technical, business and manage-
ment challenges. Private cloud workloads must access and interact with public cloud
providers, so hybrid cloud requires API compatibility and solid network connectivity.
For the public cloud piece of hybrid cloud, there are potential connectivity issues,
SLA breaches and other possible public cloud service disruptions. To mitigate these
risks, organizations can architect hybrid workloads that interoperate with multiple
public cloud providers. However, this can complicate workload design and testing.
In some cases, workloads slated for hybrid cloud must be redesigned to address the
specific providers’ APIs.
Figure 4: Rackspace- a hybrid cloud provider
3.4 Community Cloud
A community cloud in computing is a collaborative effort in which infrastructure is
shared 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.This is controlled and used by a group of
organizations that have shared interest. 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.
A community cloud is a cloud service model that provides a cloud computing
solution to a limited number of individuals or organizations that is governed, managed
and secured commonly by all the participating organizations or a third party managed
service provider.
Community clouds are a hybrid form of private clouds built and operated specif-
ically for a targeted group. These communities have similar cloud requirements and
their ultimate goal is to work together to achieve their business objectives.Community
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13. 4 Deployment Models
clouds are often designed for businesses and organizations working on joint projects,
applications, or research, which requires a central cloud computing facility for build-
ing, managing and executing such projects, regardless of the solution rented.
Figure 5: Salesforce- a community cloud provider
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14. Service Models
CHAPTER 4
4 SERVICE MODELS
4.1 Software as a Service
Software as a service (SaaS) is a software distribution model in which a third-party
provider hosts applications and makes them available to customers over the Internet.
SaaS is one of three main categories of cloud computing, alongside infrastructure as
a service (IaaS) and platform as a service (PaaS). SaaS removes the need for organi-
zations to install and run applications on their own computers or in their own data
centers. This eliminates the expense of hardware acquisition, provisioning and main-
tenance, as well as software licensing, installation and support. Other benefits of the
SaaS model include:
Flexible payments: Rather than purchasing software to install, or additional hard-
ware to support it, customers subscribe to a SaaS offering. Generally, they pay for
this service on a monthly basis using a pay-as-you-go model. Transitioning costs to a
recurring operating expense allows many businesses to exercise better and more pre-
dictable budgeting. Users can also terminate SaaS offerings at any time to stop those
recurring costs.
Scalable usage: Cloud services like SaaS offer high scalability, which gives cus-
tomers the option to access more, or fewer, services or features on-demand.
Figure 6: Architecture for SaaS
A client requests the server for a particular software. The server on acceptance of
the request configures SSH at its end and enables X-Window Forwarding using which
the software reaches the client.
4.2 Platform as a Service
Platform as a Service (PaaS) or application platform as a Service (a-PaaS) is a category
of cloud computing services that provides a platform allowing customers to develop,
run, and manage applications without the complexity of building and maintaining
the infrastructure typically associated with developing and launching an app. PaaS
can be delivered in two ways: as a public cloud service from a provider, where the
consumer controls software deployment with minimal configuration options, and the
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15. Service Models
provider provides the networks, servers, storage, operating system (OS), middleware
(e.g. Java runtime, .NET runtime, integration, etc.), database and other services to
host the consumer’s application; or as a private service (software or appliance) inside
the firewall, or as software deployed on a public infrastructure as a service.
The advantages of PaaS are primarily that it allows for higher-level programming
with dramatically reduced complexity; the overall development of the application can
be more effective, as it has built-in infrastructure; and maintenance and enhancement
of the application is easier.[3] It can also be useful in situations where multiple devel-
opers are working on a single project involving parties who are not located nearby.
One disadvantage of PaaS offerings is that developers may not be able to use a
full range of conventional tools (e.g. relational databases, with unrestricted joins).
Another possible disadvantage is being locked in to a certain platform. However, most
PaaSes are relatively lock-in free.
Figure 7: Amazon Kinesis- a platform for Big Data applications
4.3 Infrastructure as a Service
Infrastructure as a service (IaaS) is a form of cloud computing that provides virtualized
computing resources over the internet. IaaS is one of the three main categories of
cloud computing services, alongside software as a service (SaaS) and platform as a
service (PaaS). In an IaaS model, a cloud provider hosts the infrastructure components
traditionally present in an on-premises data center, including servers, storage and
networking hardware, as well as the virtualization or hypervisor layer.
The IaaS provider also supplies a range of services to accompany those infrastruc-
ture components. These can include detailed billing, monitoring, log access, security,
load balancing and clustering, as well as storage resiliency, such as backup, replication
and recovery. These services are increasingly policy-driven, enabling IaaS users to
implement greater levels of automation and orchestration for important infrastructure
tasks. For example, a user can implement policies to drive load balancing to maintain
application availability and performance.
IaaS customers access resources and services through a wide area network (WAN),
such as the internet, and can use the cloud provider’s services to install the remaining
elements of an application stack. For example, the user can log in to the IaaS plat-
form to create Virtual Machines (VMs); install operating systems in each VM; deploy
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16. Service Models
middleware, such as databases; create storage buckets for workloads and backups; and
install the enterprise workload into that VM. Customers can then use the provider’s
services to track costs, monitor performance, balance network traffic, troubleshoot
application issues, manage disaster recovery and more.
Any cloud computing model requires the participation of a provider. The provider
is often a third-party organization that specializes in selling IaaS. Amazon Web Ser-
vices (AWS) and Google Cloud Platform (GCP) are examples of independent IaaS
providers. A business might also opt to deploy a private cloud, becoming its own
provider of infrastructure services.
Infrastructure as a Service mainly comprises of three services:-
4.3.1 Storage as a Service
Storage as a service (SaaS) is a business model in which a company leases or rents
its storage infrastructure to another company or individuals to store data. Small
companies and individuals often find this to be a convenient methodology for managing
backups, and providing cost savings in personnel, hardware and physical space. A
company providing SaaS may be called a storage service provider (SSP). Storage as a
service can also be referred to as hosted storage.
Storage can be said to be of two types:-
Object Storage
Object storage (also known as object-based storage) is a computer data storage archi-
tecture that manages data as objects, as opposed to other storage architectures like
file systems which manage data as a file hierarchy and block storage which manages
data as blocks within sectors and tracks.
Figure 8: Object Storage Architecture
Block Storage
Block storage is a type of data storage typically used in storage-area network (SAN)
environments where data is stored in volumes, also referred to as blocks. Each block
acts as an individual hard drive and is configured by the storage administrator. These
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17. Service Models
blocks are controlled by the server-based operating system, and are generally accessed
by Fibre Channel (FC), Fibre Channel over Ethernet (FCoE) or iSCSI protocols.
Because the volumes are treated as individual hard disks, block storage works well
for storing a variety of applications such as file systems and databases. While block
storage devices tend to be more complex and expensive than file storage, they also
tend to be more flexible and provide better performance.
Figure 9: Block Storage Architecture
4.3.2 Containers as a Service
A container image is a lightweight, stand-alone, executable package of a piece of soft-
ware that includes everything needed to run it: code, runtime, system tools, system
libraries, settings. Available for both Linux and Windows based apps, containerized
software will always run the same, regardless of the environment. Containers isolate
software from its surroundings, for example differences between development and stag-
ing environments and help reduce conflicts between teams running different software
on the same infrastructure.
Figure 10: Difference between a Container and a Virtual Machine
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18. Service Models
Virtual Machines
Virtual machines (VMs) are an abstraction of physical hardware turning one server
into many servers. The hypervisor allows multiple VMs to run on a single machine.
Each VM includes a full copy of an operating system, one or more apps, necessary
binaries and libraries - taking up tens of GBs. VMs can also be slow to boot.
Containers
Containers are an abstraction at the app layer that packages code and dependencies
together. Multiple containers can run on the same machine and share the OS kernel
with other containers, each running as isolated processes in user space. Containers
take up less space than VMs (container images are typically tens of MBs in size), and
start almost instantly.
Figure 11: Docker is the most optimized and largest used conatinerization tool
4.3.3 Network as a Service
Network-as-a-service (NaaS) is a business model for delivering network services vir-
tually over the Internet on a pay-per-use or monthly subscription basis. From the
customer’s point of view, the only thing required to create an information technology
(IT) network is one computer, an Internet connection and access to the provider’s
NaaS portal. This concept can be appealing to new business owners because it saves
them from spending money on network hardware and the staff it takes to manage a
network in-house. In essence, the network becomes a utility, paid for just like electric-
ity or water or heat. Because the network is virtual, all its complexities are hidden
from view.
NaaS isn’t a new concept, but its deployment has been hindered by some of the
same concerns that have affected other cloud computing services, especially questions
about the provider’s ability to guarantee high availability (HA). Other concerns in-
clude dealing with service level agreements (SLAs), compliance issues related to data
sovereignty and the possibility of vendor lock-in.
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19. Service Models
From the customer’s point of view, the only thing required to create an information
technology (IT) network is one computer, an Internet connection and access to the
provider’s NaaS portal. This concept can be appealing to new business owners because
it saves them from spending money on network hardware and the staff it takes to
manage a network in-house. In essence, the network becomes a utility, paid for just
like electricity or water or heat. Because the network is virtual, all its complexities
are hidden from view.
NaaS isn’t a new concept, but its deployment has been hindered by some of the
same concerns that have affected other cloud computing services – especially questions
about the provider’s ability to guarantee high availability (HA). Other concerns in-
clude dealing with service level agreements (SLAs), compliance issues related to data
sovereignty and the possibility of vendor lock-in.
Figure 12: AWS Network Load Balancer
4.3.4 Implementing IaaS on a small scale
Figure 13: IaaS Architecture
Client requests the server for an OS with RAM, CPU and Hard Disk. The server
configures its resources and pools them to the client using VNC (for mobile phones)
and No-VNC (for PC).
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20. Comparison of service models
CHAPTER 5
5 Comparison between the three service models
Figure 14: Comparison between all the service models
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21. Challenges
CHAPTER 6
6 CHALLENGES TO CLOUD COMPUTING
Cloud computing challenges have always been there. Companies are increasingly aware
of the business value that cloud computing brings and are taking steps towards transi-
tion to the cloud. A smooth transition entails a thorough understanding of the benefits
as well as challenges involved. Like any new technology, the adoption of cloud com-
puting is not free from issues. Some of the most important challenges are as follows:-
6.1 Security and Privacy
The main challenge to cloud computing is how it addresses the security and privacy
concerns of businesses thinking of adopting it. The fact that the valuable enterprise
data will reside outside the corporate firewall raises serious concerns. Hacking and
various attacks to cloud infrastructure would affect multiple clients even if only one
site is attacked. These risks can be mitigated by using security applications, encrypted
file systems, data loss software, and buying security hardware to track unusual behavior
across servers.
It is difficult to assess the costs involved due to the on-demand nature of the ser-
vices. Budgeting and assessment of the cost will be very difficult unless the provider
has some good and comparable benchmarks to offer. The service-level agreements
(SLAs) of the provider are not adequate to guarantee the availability and scalabil-
ity. Businesses will be reluctant to switch to cloud without a strong service quality
guarantee.
6.2 Interoperability and Portability
Businesses should have the leverage of migrating in and out of the cloud and switching
providers whenever they want, and there should be no lock-in period. Cloud computing
services should have the capability to integrate smoothly with the on-premise IT.
6.3 Reliability and Availability
Cloud providers still lack round-the-clock service; this results in frequent outages. It is
important to monitor the service being provided using internal or third-party tools. It
is vital to have plans to supervise usage, SLAs, performance, robustness, and business
dependency of these services.
6.4 Performance and Bandwidth Cost
Businesses can save money on hardware but they have to spend more for the band-
width. This can be a low cost for smaller applications but can be significantly high
for the data-intensive applications. Delivering intensive and complex data over the
network requires sufficient bandwidth. Because of this, many businesses are waiting
for a reduced cost before switching to the cloud.
All these challenges should not be considered as road blocks in the pursuit of cloud
computing. It is rather important to give serious consideration to these issues and the
possible ways out before adopting the technology.
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22. Conclusion
CHAPTER 7
7 CONCLUSION
Cloud computing is changing the way IT departments buy IT. Businesses have a
range of paths to the cloud, including infrastructure, platforms and applications that
are available from cloud providers as online services. Many people may be confused by
the range of offerings and the terminology used to describe them and will be unsure
of the risk and benefits. There are many more players in the on-demand market that
many reports acknowledge. These range from basic infrastructure offerings (IaaS),
through platform support (PaaS) to full applications (SaaS). The long term cost of
ownership may at first not seem to add up, but take into consideration other factors
such as reduced risk and added value and for many organisations on-demand services
make a lot of sense
”I dont need a hard disk in my computer if I can get to the server faster
carrying around these non-connected computers is byzantine by comparison.
Steve Jobs, Co-founder, CEO and Chairman of Apple Inc.”
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23. References
CHAPTER 8
8 REFERENCES
• Colin Ting Si Xue, Felicia Tiong Wee Xin: Benefits And Challenges Of The
Adoption Of Cloud Computing In Business, International Journal on Cloud
Computing: Services and Architecture (IJCCSA) Vol. 6, No. 6, Asia Pa-
cific University of Technology and Innovation Technology Park Malaysia Kuala
Lumpur, Malaysia, December 2016
• Ahmad Rashidi and Naser Movahhedinia: model for trust in Cloud Computing,
International Journal on Cloud Computing: Services and Architecture(IJCCSA),Vol.2,
No.2, University of Isfahan, Isfahan, Iran, April 2012
• Sinung Suakanto, Suhono H Supangkat, Suhardi, Roberd Saragih: Performance
measurement of Cloud Computing Services, International Journal on Cloud
Computing: Services and Architecture (IJCCSA),Vol.2, No.2, Bandung Insti-
tute of Technology, Bandung, Indonesia, April, 2012
• John Fink: Docker, a Software as a Service, Operating System- Level Virtual-
ization Framework, International Journal on Cloud Computing: Services and
Architecture (IJCCSA),Vol.2, No.2, McMaster University, December, 2014.
• Sudha, Harish G, Nandan, Usha: Performance Analysis Of Kernal-Based Virtual
Machine, International Journal of Computer Science And Information Technol-
ogy ,Vol 5, No 1, Department of MCA, R V College of Engineering, Bangalore,
February 2013
• https://aws.amazon.com/documentation/
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