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Cloud Service Models
SaaS, PaaS, and IaaS are the three main cloud computing service model categories.
You can access all three via an Internet browser or online apps available on different devices.
The cloud service model enables the team to collaborate online instead of offline creation and
then share online.
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Software as a Service (SaaS)
Software as a Service (SaaS) is a web-based deployment model that makes the software
accessible through a web browser. SaaS software users don’t need to care where the software
is hosted, which operating system it uses, or even which programming language it is written
in. The SaaS software is accessible from any device with an internet connection.
This cloud service model ensures that consumers always use the most current version
of the software. The SaaS provider handles maintenance and support. In the SaaS model, users
don’t control the infrastructure, such as storage, processing power, etc.
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Characteristics of SaaS
There are the following characteristics of SaaS:
It is managed from a central location.
Hosted directly on a remote server.
It is accessible over the Internet.
SaaS users are not responsible for hardware and software updates.
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The services are purchased on a pay-as-per-use basis.
Advantages SaaS
Here are the important advantages/pros of SaaS:
The biggest benefit of using SaaS is that it is easy to set up, so you can start using it
instantly.
Compared with on-premises software, it is more cost-effective.
You don’t need to manage or upgrade the software, as it is typically included in a SaaS
subscription or purchase.
It won’t use your local resources, such as the hard disk typically required to install
desktop software.
It is a cloud computing service category that provides a wide range of hosted
capabilities and services.
Developers can easily build and deploy web-based software applications.
You can easily access it through a browser.
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Disadvantages SaaS
Here are the important cons/drawbacks of SaaS:
Integrations are up to the provider, so it’s impossible to “patch” an integration on your
end.
SaaS tools may become incompatible with other tools and hardware already used in
your business.
You depend on the SaaS company’s security measures, so your data may be
compromised if any leaks occur.
Consider Before SaaS Implementation
Need to consider before SaaS implementation:
It would help if you opted for configuration over customization within a SaaS-based
delivery model.
You must carefully understand the usage rates and set clear objectives to achieve the
SaaS adoption.
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You can complement your SaaS solution with integrations and security options to make
it more user-oriented.
Platform as a Service (PaaS)
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Platform-as-a-Service (PaaS) provides a cloud computing framework for software
application creation and deployment. It is a platform for the deployment and management of
software apps. This flexible cloud computing model scales up automatically on demand. It also
manages the servers, storage, and networking, while the developers manage only the
application part. It offers a runtime environment for application development and deployment
tools.
This Model provides all the facilities required to support the complex life cycle of
building and delivering web applications and services entirely for the Internet. This cloud
computing model enables developers to rapidly develop, run, and manage their apps without
building and maintaining the infrastructure or platform.
Characteristics of PaaS
There are the following characteristics of PaaS:
Builds on virtualization technology, so computing resources can easily be scaled up
(Auto-scale) or down according to the organization’s needs.
Support multiple programming languages and frameworks.
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Integrates with web services and databases.
Advantages PaaS
Here are the important benefits/pros of PaaS:
Simple, cost-effective development and deployment of apps
Developers can customize SaaS apps without the headache of maintaining the software
Provide automation of Business Policy
Easy migration to the Hybrid Model
It allows developers to build applications without the overhead of the underlying
operating system or cloud infrastructure
Offers freedom to developers to focus on the application’s design while the platform
takes care of the language and the database
It helps developers to collaborate with other developers on a single app
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Disadvantages of SaaS
Here are the important cons/drawbacks of PaaS:
You have control over the app’s code and not its infrastructure.
The PaaS organization stores your data, so it sometimes poses a security risk to your
app’s users.
Vendors provide varying service levels, so selecting the right services is essential.
The risk of lock-in with a vendor may affect the ecosystem you need for your
development environment.
Consider Before PaaS Implementation
Here are essential things you need to consider before PaaS implementation:
Analyze your business needs, decide the automation levels, and also decides whether
you want a self-service or fully automated PaaS model.
You need to determine whether to deploy on a private or public cloud.
Plan through the customization and efficiency levels.
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Infrastructure as a Service (IaaS)
Infrastructure-as-a-Service (IaaS) is a cloud computing service offering on-demand
computing, storage, and networking resources. It usually works on a pay-as-you-go basis.
Organizations can purchase resources on-demand and as needed instead of buying the
hardware outright.
The IaaS cloud vendor hosts the infrastructure components, including the on-premises
data center, servers, storage, networking hardware, and the hypervisor (virtualization layer).
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This Model contains the basic building blocks for your web application. It provides
complete control over the hardware that runs your application (storage, servers, VMs, networks
& operating systems). IaaS model gives you the best flexibility and management control over
your IT resources.
Characteristics of IaaS
There are the following characteristics of IaaS:
Resources are available as a service
Services are highly scalable
Dynamic and flexible Cloud Service Model
GUI and API-based access
Automate the administrative tasks
Advantages of IaaS
Here are the important benefits/pros of PaaS:
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Easy to automate the deployment of storage, networking, and servers.
Hardware purchases can be based on consumption.
Clients keep complete control of their underlying infrastructure.
The provider can deploy the resources to a customer’s environment anytime.
It can be scaled up or downsized according to your needs.
Disadvantages of IaaS
Here are the important Cons/drawbacks of IaaS:
You should ensure that your apps and operating systems are working correctly and
providing the utmost security.
You’re in charge of the data, so if any of it is lost, it’s up to you to recover it.
IaaS firms only provide the servers and API, so you must configure everything else.
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Consider Before IaaS Implementation
Here are some specific considerations you should remember before IaaS Implementation:
You should clearly define your access needs and your network’s bandwidth to
facilitate smooth implementation and functioning.
Plan out detailed data storage and security strategy to streamline the business process.
Ensure that your organization has a proper disaster recovery plan to keep your data
safe and accessible.
How can select the Best SaaS Service Provider
Here are some essential criteria for selecting the best cloud service provider:
Financial stability: Look for a well-financed cloud provider that has steady profits
from the infrastructure. If the company shuts down because of monetary issues, your
solutions will also be in jeopardy.
Industries that prefer the solution: Before finalizing cloud services, examine its
existing clients and markets. Your cloud service provider should be popular among
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companies in your niche or neighboring ones.
Datacenter locations: To avoid safety risks, ensure that cloud providers enable your
data’s geographical distribution.
Encryption standards: You should make sure the cloud provider supports major
encryption algorithms.
Check accreditation and auditing: The widely used online auditing standard is
SSAE. This procedure helps you to verify the safety of online data storage. ISO
27001 certificate verifies that a cloud provider complies with international safety
standards for data storage.
Backup: The provider should support incremental backups so that you can store
offsite and quickly restore.
Driving Factors and Challenges of Cloud
Data Security and Privacy
Data security is a major concern when switching to cloud computing. User or
organizational data stored in the cloud is critical and private. Even if the cloud service provider
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