Cloud Computing: Cloud Service Models
Cloud Computing: Cloud Service Models
A cloud refers to a distinct IT environment that is designed for the purpose of remotely provisioning scalable and measured IT resources. The term originated as a metaphor for the Internet which is, in essence, a network of networks providing remote access to a set of decentralized IT resources. Prior to cloud computing becoming its own formalized IT industry segment, the symbol of a cloud was commonly used to represent the Internet in a variety of specifications and mainstream documentation of Web-based architectures. Let's discuss the various service models of Cloud Computing in this article.
Earlier article: Cloud Computing: Characteristics
You are probably using cloud computing right now, even if you don’t realise it. If you use an online service to send email, edit documents, watch movies or TV, listen to music, play games or store pictures and other files, it is likely that cloud computing is making it all possible behind the scenes.
Let's get to our topic.
Service Models of Cloud Computing
The service models are dynamically changing as cloud providers come out with new offerings focused on being competitive, increase market share, each with the aim to becoming one-stop shop. Mainly, there are five Cloud Computing Service based models. These are given as follows:
Infrastructure as a Service (IaaS)
It is the foundation of cloud services. It provides clients with access to server hardware, storage, bandwidth and other fundamental computing resources. The service is typically paid for on a usage basis. The service may also include dynamic scaling so that if the customer needs more resources than expected, s/he can get them on the fly (probably to a given limit). It provides access to shared resources on need basis, without revealing details like location and hardware to clients.
Software as a Service (SaaS)
It includes a complete software offering on the cloud. Users can access a software application hosted by the cloud vendor on pay-per-use basis. This is a well-established sector. SaaS is a model of software deployment where an application is hosted as a service provided to customers across the Internet by removing the need to install and run an application on a user’s own computer.
It is seen as a way for businesses to get the same benefits as commercial software with smaller cost outlay. SaaS can alleviate the burden of software maintenance and support but users relinquish control over software versions and requirements.
Platform as a Service (PaaS)
PaaS (Platform as a Service), as the name suggests, provides you computing platforms which typically includes operating system, programming language execution environment, database, web server etc. Examples: AWS Elastic Beanstalk, Windows Azure, Heroku, Force.com, Google App Engine, Apache Stratos.
Say, Google App Engine allows clients to run their web applications (i.e. software that can be accessed using a web browser such as Internet Explorer over the internet) on Google’s infrastructure. It has evolved from Software as a Service (SaaS) and Infrastructure as a service (IaaS).The major drawback of Platform as a environment and stack of software components.
Network as a Service (NaaS)
Network-as-a-service (NaaS) is a business model for delivering network services virtually over the Internet on a pay-per-use or monthly subscription basis.
It is a category of cloud services where the capability provided to the cloud service user is to use network/transport connecting services. NaaS involves optimization of resource allocation by considering network and computing resources as a whole. Some of the examples are: Virtual Private Network, Mobile Network Virtualization etc.
Communication as a Service (CaaS)
CaaS has evolved in the same lines as SaaS. CaaS is an outsourced enterprise communication solution that can be leased from a single vender. The CaaS vendor is responsible for all hardware and software management and offers guaranteed Quality of Service (QoS). Such communications can include voice over IP (VoIP or Internet telephony), instant messaging (IM), collaboration and videoconference applications using fixed and mobile devices
Enterprises have to select the right service model based on their specific requirements. The selection has to be done considering various factors such as cost benefit analysis, relevant risks, security and controls and the criticality of the data and services. Typically, the enterprises would choose the model, which offers them the best savings with the required security.
We shall discuss the advantages and disadvantages of Cloud Computing in the coming articles, stay tuned for that.
And like always, if you have any queries, doubts or suggestions, please let me know. Just click on Ask Questions
