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| Cloud Service Models | IndianTechnoEra |
Service models
There are 3 service models. Choose the service you need.
A Simple Analogy
Say you just a moved to a city and you are looking for a place to live.
What is your choice?
Build a new house,
buy an empty house, or
live in a hotel.
Let's build a new house
You can fully control everything your like, your view, new House to have. But that is a hard work.
If you buy an empty house
You can customize some part of your house, but never change the original architecture.
How about live in hotel?
Live in hotel will be a good idea if the only thing you care is enjoy your life. There is nothing you can do with the house expect living in it.
Now let's translate to cloud computing.
Service Models Overview
What if you want to have an IT department ?
Similar to build a new house in previous analogy :
You can rent some virtualized infrastructure and build up your own IT system among those resources, which may be fully controlled.
Technical speaking, use the Infrastructure as a Service (IaaS) solution:
Similar to buy an empty house in previous analogy
You can directly develop your IT system through one cloud platform, and do not care about any lower level resource management.
Technical speaking, use the Platform as a Service (PaaS) solution.
Similar to live in a hotel in previous analogy
You can directly use some existed IT system solutions, which were provided by some cloud application service provider, without knowing any detail technique about how these service was achieved.
Technical speaking, use the Software as a Service (SaaS) solution.
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| Service model overview | IndianTechnoEra |
Service models
Infrastructure as a Service
Platform as a Service
Software as a Service
Infrastructure as a Service
Infrastructure as a Service - IaaS
The capability provided to the consumer is to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications.
The consumer does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, deployed applications, and possibly limited control of select networking components .
Examples : Amazon EC2, Eucalyputs, OpenNebula, … etc
System Architecture - IaaS
Enabling technique - Virtualization
Virtualization is an abstraction of logical resources away from underlying physical resources.
Virtualization technique shift OS onto hypervisor.
Multiple OS share the physical hardware and provide different services.
Improve utilization, availability, security and convenience.
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| Traditional stack Virtualized stack |
Properties supported by virtualization technique :
Manageability and Interoperability
Availability and Reliability
Scalability and Elasticity
Provide service –Resource Management Interface
Several types of virtualized resource :
Virtual Machine – As an IaaS provider, we should be able to provide the basic virtual machine operations, such as creation, suspension, resumption and termination, …etc.
Virtual Storage – As an IaaS provider, we should be able to provide the basic virtual storage operations, such as space allocation, space release, data writing and data reading, …etc.
Virtual Network – As an IaaS provider, we should be able to provide the basic virtual network operations, such as IP address allocation, domain name register, connection establishment and bandwidth provision, …etc.
Provide service – System Monitoring Interface
Several types of monitoring metrics :
Virtual Machine – As an IaaS provider, we should be able to monitor some system states of each virtual machine, such as CPU loading, memory utilization, IO loading and internal network loading, …etc.
Virtual Storage – As an IaaS provider, we should be able to monitor some storage states of each virtual storage, such as virtual space utilization, data duplication and storage device access bandwidth, …etc.
Virtual Network – As an IaaS provider, we should be able to monitor some network states of each virtual network, such as virtual network bandwidth, network connectivity and network load balancing, …etc.
Issa Summary
IaaS is the deployment platform that abstract the infrastructure.
IaaS enabling technique:
Virtualization;
Server Virtualization
Storage Virtualization
Network Virtualization
IaaS provided services:
Resource Management Interface
System Monitoring Interface
Platform as a service
Platform as a Service - PaaS
The capability provided to the consumer is to deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages and tools supported by the provider.
The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, or storage, but has control over the deployed applications and possibly application hosting environment configurations.
Examples: Microsoft Windows Azure, Google App Engine, Hadoop, … etc
System Architecture - PaaS
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| Platform as a service system architecture | IndianTechnoEra |
Enabling technique – Runtime Environment Design
Runtime environment refers to collection of software services available. Usually implemented by a collection of program libraries.
Common properties in Runtime Environment :
Manageability and Interoperability
Performance and Optimization
Availability and Reliability
Scalability and Elasticity
Provide service – Programming IDE
Users make use of programming IDE to develop their service among PaaS:
This IDE should integrate the full functionalities which supported from the underling runtime environment.
This IDE should also provide some development tools, such as profiler, debugger and testing environment.
The programming APIs supported from runtime environment may be various between different cloud providers, but there are still some common operating functions.
Computation, storage and communication resource operation
Provide service – System Control Interface
Police-Based Control
Typically described as a principle or rule to guide decisions and achieve rational outcome(s)
Make the decision according to some requirements
Workflow Control
Describe the flow of installation and configuration of resources
Workflow processing daemon delivers speedy and efficient construction and management of cloud resources
Paas Summary
PaaS is the development platform that abstract the infrastructure, OS, and middleware to drive developer productivity.
PaaS enabling technique:
Runtime Environment
PaaS provide services:
Programming IDE
Programming APIs
Development tools
System Control Interface:
Policy based approach
Workflow based approach
Software as a Service
Software as a Service - SaaS
The capability provided to the consumer is to use the provider’s applications running on a cloud infrastructure. The applications are accessible from various client devices through a thin client interface such as a web browser (e.g., web-based email).
The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, storage, or even individual application capabilities, with the possible exception of limited user-specific application configuration settings.
Examples of software as a service - Saas:
Google Apps (e.g., Gmail, Google Docs, Google sites, …etc),
SalesForce.com,
EyeOS … etc
System Architecture - SaaS
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| System Architecture of software as service | IndianTechnoEra |
Enabling Technique – Web Service
Web 2.0 is the trend of using the full potential of the web
Viewing the Internet as a computing platform
Running interactive applications through a web browser
Leveraging interconnectivity and mobility of devices
Enhanced effectiveness with greater human participation
Properties provided by Internet :
Accessibility and Portability
Provide service – Web-based Applications
Conventional applications should translate their access interface onto web-based platform.
Applications in different domains
General Applications – Applications which are designed for general propose, such as office suit, multimedia and instant message, …etc.
Business Applications – Application which are designed for business propose, such as ERP, CRM and market trading system, …etc.
Scientific Applications – Application which are designed for scientific propose, such as aerospace simulation and biochemistry simulation, …etc.
Government Applications – Applications which are designed for government propose, such as national medical system and public transportation system service, …etc.
Provide service – Web Portal
Apart from the standard search engine feature, web portals offer other services such as e-mail, news, stock prices, information, databases and entertainment.
Portals provide a way for enterprises to provide a consistent look and feel with access control and procedures for multiple applications and databases, which otherwise would have been different entities altogether.
Some examples :
iGoogle
MSNBC
Netvibes
Yahoo!
SaaS - Summary
SaaS is the finished applications that you rent and customize.
SaaS enabling technique:
Web Service
SaaS provide services
Web-based Applications
General applications
Business applications
Scientific applications
Government applications
Web Portal