Cloud Services

Cloud computing is typically classified in two ways:

1. Location of the cloud computing
2. Type of services offered

Most time a Cloud can be described as a Stack, a broad range of services that are build on top of another. This article tells us the types of services a cloud offer,

Cloud Providers have build the cloud infrastructure on a well designed services with clearly defined interfaces. These services allow the Cloud to Scale. One the other hand, applications too going to Cloud are built as services.

Here are the services provided by Cloud,

Anything-as-a-Service (XaaS) is yet another service model, which

includes Network-as-a-Service, Business-as-a-Service, Identity-as-a-

Service, Database-as-a-Service or Strategy-as-a-Service.

Software as Service(SaaS)

Software that is deployed over internet. Applications that are deployed to the Cloud and provides services to the users who access them over the internet. Cloud provides the infrastructure and platforms that run the applications. This is also referred as "On-demand Software". Uses gains access to the software using the login Credentials

Cloud users do not have control over the cloud infrastructure and platform where the application runs. This eliminates the need to install and run the application on the cloud user's own computers, which simplifies maintenance and support.

Example - Microsoft Office 365

Characteristics of SAAS

Some of the characteristics of Saas are,

1) Web access to commercial software deployed in Cloid

2) Application is developed as on-to-many model

3) No Software upgrades and patches

4) Application Programming Interfaces (APIs) allow for integration between different pieces of software

Where can Saas be used,

SAAS implementations are seen every where these days. One of the most important example is the E-Mail System. SAAS is used

1) When applications where there is significant interplay between the organization and the outside world like E-mail etc

2) Application with multiple access base like web and mobile.

3) Application that is used for a shorter term.

4) Software where demand spikes significantly

More over SAAS may not be use-full where

1) Applications where extremely fast processing of real time data is required
2) Applications where legislation or other regulation does not permit data being hosted externally

Platform as a Service (PaaS)

This type of cloud service offers development environment that IT organizations can use to create cloud based applications. This includes services that developers build applications on the top of the infrastructure. This might include developer tools that are offered as a service to build services, or even data access and database services, or even billing services.

A cloud provider provides the computing platform, typically Operating system, Programming language execution environment, database and web server. Application developers can develop and run their software solutions on a cloud platform without the cost and complexity of buying and managing the underlying hardware and software layers

Example - Google App Engine, Microsoft Azura

Characteristics of PAAS

1) Integration with web services and databases via common standards

2) Support for development team collaboration – some PaaS solutions include project planning and communication tools

Where can Paas be used,

PaaS is especially useful in any situation where multiple developers will be working on a development project or where other external parties need to interact with the development process and finally PaaS is useful where developers wish to automate testing and deployment services

Infrastructure as a Service (IaaS)

This service layer offers storage and compute resources that developers and IT organizations use to deliver their custom applications. Its a way of delivering Cloud Computing infrastructure – servers, storage, network and operating systems – as an on-demand service. Rather than purchasing servers, software, datacenter space or network equipment, clients instead buy those resources as a fully outsourced service on demand

Examples - Amazon Web Services, Rack Space

Characteristics of IaaS

1) Resources are distributed as a service
2) Allows for dynamic scaling
3) Generally includes multiple users on a single piece of hardware

Where IaaS Makes Sense

1) For new organizations without the capital to invest in hardware 

2) Where the organization is growing rapidly and scaling hardware would be problematic 

3) Where demand is very volatile – any time there are significant spikes and troughs in terms of demand on the infrastructure