In this article, we will try to understand in the simplest possible way; What is a cloud? What are different cloud offerings? How does it work for you?
Cloud computing constitutes a broad range of services. The web is the common thread between all of these. So something sitting on your desktop and able to operate on its own is not a cloud service.
Key characteristics of a cloud-based solution are:
- It is available on demand.
- It can be accessed through standard platforms like desktop, laptop, mobile.
- It can be used by multiple people.
- People can share resources.
- It can easily handle the increase/decrease of the user base.
- The solution can scale up/down easily.
- Billing for the service can be easily measured.
There are different types of cloud computing services commonly classified as Software as a Service (SaaS), Platform as a Service (PaaS) and Infrastructure as a Service (IaaS). In a very simplistic explanation:
- SaaS – is software delivered over the web.
- PaaS – is platform delivered over the web, for the creation of the software.
- IaaS – is infrastructure (hardware/software) delivered over web as an on-demand leased service.
Let’s take a deeper look at these services.
Software as a Service (SaaS)
Characteristics:
- It is available through the web either as a paid/free service.
- It is centrally managed and delivered to all.
- Software users should not require updating software or applying patches.
- Exposes APIs (Application Programming Interfaces) to allow integration between different modules.
Where does it work?
- Generic solutions are used by a variety of users.
- Solutions that need to be used over multiple channels (web, mobile), locations (home, office, on the way)
Where it doesn't work?
- Data sensitive applications with legal limitations.
- Solutions are used by a defined set of users (employees of a specific company)
Example – Salesforce.com is the best example of software delivered as a Service.
Platform as a Service (PaaS)
Characteristics:
- Provides services to help in the development of software products.
- Provides services and solutions to develop, test, deploy, host, manage software applications.
- Allows for multiple developers can work on the platform in parallel.
- Provides capability for failover, scalability, load balancing within the platform.
- Supports standard API, third party, DB integration protocols.
- Provides built-in support for features such as subscription management, billing for the applications built using the platform.
Where does it work?
- All the all technical stack requirements are met by platform offerings.
- Automation is paramount in testing, build, release.
Where it doesn't work?
- The application needs to be portable from a hosting perspective.
- Proprietary languages, technologies, practices would be required.
Example – Force.com is the best example of a platform delivered as a Service. Another very popular example is Google App Engine which provides a complete platform to enable the development of software applications. If your software technical requirements can be met completely by such platforms, PaaS is for you.
Infrastructure as a Service (IaaS)
Characteristics:
- Resources (hardware and software) are available as service.
- Allows for scaling up/down dynamically.
- Have billing/pricing based on usage.
- Provides capability for failover, scalability, load balancing within the platform.
- Resources can be shared between different users.
Where does it work?
- Requirements can change dynamically; may go up/down.
- For people/companies who do not want to invest (both money and labour) too much on hardware.
- For people who want to try something temporarily.
Where it doesn't work?
- Cases in which there are too much regulatory, security, legal factors are involved related to storage.
Example – Amazon AWS, Rackspace are some of the leaders in this space. People and organizations that want to move to Cloud computing should identify their needs and based on that find the cloud consulting services offering and model that suits best for their business needs. Cloud offers a lot; not everything may be useful for everybody.