Platform as a Service | PaaS:-
PaaS cloud computing platform is a developer programming platform which is created for the programmer to develop, test, run and manage the applications.
A developer is able to write the application as well as deploy it directly into this layer easily.
PaaS allows you to create applications using software components that are built into the PaaS (middleware). Applications using PaaS inherit cloud characteristic such as scalability, high-availability, multi-tenancy, SaaS enablement, and more
PaaS extend and abstract the IaaS layer by removing the hassle of managing the individual virtual machine.
In PaaS cloud computing platform, back end scalability is handled by the cloud service provider and the end user does not have to worry about to manage the infrastructure.
PaaS services are hosted in the cloud and accessed by users simply via their web browser.
All the infrastructure to run the applications will be over the internet.
Apprenda is one provider of a private cloud PaaS for .NET and Java.
PaaS providers provide the Programming languages, Application frameworks, Databases, and Other tools:
1. Programming languages
PaaS providers provide various programming languages for the developers to develop the applications. Some popular programming languages provided by PaaS providers are Java, PHP, Ruby, Perl, and Go.
2. Application frameworks
PaaS providers provide application frameworks to easily understand the application development. Some popular application frameworks provided by PaaS providers are Node.js, Drupal, Joomla, WordPress, Spring, Play, Rack, and Zend.
PaaS providers provide various databases such as ClearDB, PostgreSQL, MongoDB, and Redis to communicate with the applications.
4. Other tools
PaaS providers provide various other tools that are required to develop, test, and deploy the applications.
Popular PaaS Providers
The below table shows some popular PaaS providers and services that are provided by them –
|Google App Engine (GAE)||App Identity, URL Fetch, Cloud storage client library, Logservice|
|Salesforce.com||Faster implementation, Rapid scalability, CRM Services, Sales cloud, Mobile connectivity, Chatter.|
|Windows Azure||Compute, security, IoT, Data Storage.|
|AppFog||Justcloud.com, SkyDrive, GoogleDocs|
|Openshift||RedHat, Microsoft Azure.|
|Cloud Foundry from VMware||Data, Messaging, and other services.|
Advantages of PaaS cloud computing layer
1) Simplified Development:-Developers can focus on development and innovation without worrying about the infrastructure.
2) Lower risk: No requirements of up-front investment in hardware and software. Developers only need a PC and an internet connection to start building applications.
3) Prebuilt business functionality: – Some PaaS vendors also provide already defined business functionality so that users can avoid building everything from very scratch and hence can directly start the projects only.
4) Instant community:- PaaS vendors frequently provides online communities where developer can get the ideas, share experiences and seek advice from others.
5) Scalability: – Applications deployed can scale from one to thousands of users without any changes to the applications.
Disadvantages of PaaS cloud computing layer:-
1) Vendor lock-in:– One have to write the applications according to the platform provided by PaaS vendor so migration of an application to another PaaS vendor would be a problem.
2) Data Privacy:- Corporate data, whether it can be critical or not, will be private so if it is not located within the walls of the company there can be a risk in terms of privacy of data.