Cloud computing and types of services

Cloud computing defined as dynamically scalable shared resources accessed over a network. Cloud computing security sometimes referred to simply as "cloud security" is an evolving sub domain of computer security, network security, and more broadly information security. It refers to a broad set of policies, technologies, and controls deployed to protect data, applications, and the associated infrastructure of cloud computing. Cloud computing services such as Amazon EC2 and Windows Azure are becoming more and more popular but it seems many people are still unclear as to what exactly the buzzword “Cloud computing” actually means.  In its simplest form, the principle of Cloud computing is the provision of computing resources via a network.

There is a critical need to securely store, manage, share and analyze massive amounts of complex data. Because of the critical nature of the applications, it is important that clouds be secure. The major security challenge with clouds is that the owner of the data may not have control of where the data is placed. This is because if one wants to exploit the benefits of using cloud computing. Therefore, we need to safeguard the data in the midst of untrusted processes. Cloud Computing Security Issues depend on the type of Cloud Computing used. The framework for Cloud Computing Security is the same. The concept of cloud computing represents a shift in thought, in that end users need not know the details of a specific technology. Clouds allow users to pay for whatever resources they use, allowing users to increase or decrease the amount of resources requested as needed. Cloud servers can be used to motivate the initiation of a business and ease its financial burden in terms of Capital Expenditure and Operational Expenditure.

TYPES OF CLOUD SERVICES

Cloud services are usually divided in the three main types, Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS) and Infrastructure-as-a-Service (IaaS).

Software as a Service (SaaS)

Software as a service (SaaS) includes a complete software offering on the cloud. Users can access a software application hosted by the cloud vendor on pay-per-use basis. The applications are typically offered to the clients via the Internet and are managed completely by the Cloud provider. That means that the administration of these services such as updating and patching are in the provider’s responsibility. This is a well established sector. One big benefit of SaaS is that all clients are running the same software version and new functionality can be easily integrated by the provider and is therefore available to all clients. The pioneer in this field has been Salesforce.com offering in the online Customer Relationship Management (CRM) space. Other examples are online email providers like Google, Gmail, Microsoft’s hotmail, Google docs and Microsoft’s online version of office called BPOS (Business Productivity Online Standard Suite).

Platform-as-a-Service (PaaS)

Platform as a Service (PaaS) involves offering a development platform on the cloud. It’s more popular and mostly utilized by the developer community and was likely started with the introduction and popularity of Linux open source code. This cloud computing model provides a platform for developers to code, test and experiment new software without the complexity of setting up and maintaining test, development and production servers. Platforms provided by different vendors are typically not compatible. Typical players in PaaS are Google’s Application Engine, Microsoft’s Azure, and Salesforce.com.

Infrastructure-as-a-Service (IaaS)

This is hardware related services using the principles of cloud computing. It delivers hardware resources such as CPU, disk space or network components as a service. These resources are usually delivered as a virtualization platform by the Cloud provider and can be accessed across the Internet by the client. Leading vendors that provide Infrastructure as a service are Amazon EC2, Amazon S3, Rackspace Cloud Servers and Flexiscale.

Figure. Cloud Services

The above classification is well accepted in the industry. David Linthicum describes a more granular classification on the basis of service provided. These are listed below:

• Storage-as-a-service
• Database-as-a-service
• Information-as-a-service
• Process-as-a-service
• Application-as-a-service
• Platform-as-a-service
• Integration-as-a-service
• Security-as-a-service
• Management/Governance-as-a-service
• Testing-as-a-service
• Infrastructure-as-a-service