What is Public Cloud
Cloud computing is a system of interlinked and networked servers that seeks to provide high-performance services comparable to supercomputing used by research institutions and the military, to the public mass. The network servers use specialized connections to connect the servers thus ensuring the spread of task within the system is done to maximize the computing power of the system.
Cloud computing can be classified as either public or private cloud computing where public computing, such as Amazon Elastic Computer Cloud provides services to anyone and on an open network usually the internet. Private clouds are cloud computing services that are preserved for a few individuals or organizations and are therefore not open to the public. The security systems put in place in private computing are usually high and at times unnecessary for personal uses as compared to those used in public clouds.
Characteristics of Public Cloud
There are three distinct characteristics of public cloud computing that distinguishes them from other forms of online computing services. Public cloud computing is sold on demand (by-the-hour or by-the-minute), the services are fully managed by the service provider and it is elastic.
The goal of cloud computing is to set up a pool of shared computer services that are can be accessed by many people who in turn do not have to privately purchase each and every service they may need. A good example is storage space, which can be provided in a public cloud system.
Broadly public cloud services are divided into three models;
- Infrastructure-as-a-service (IaaS)
- Platform-as-a-service (PaaS) and finally
- Software-as-a-service (SaaS)
IaaS is a public cloud package where customers are provided with virtual servers and online storage space. Customers are also provided with application program interfaces (API) which allow the clients to independently use their virtual servers and storage spaces by enabling the clients to start, stop and configure their servers as they wish.
SaaS is a model of software distribution and licensing where access to the software is attained via the internet to a hosting cloud. Clients pay for the services by subscriptions that may be monthly, bi-annual, annually or any period of time that befits the customer.
PaaS is a model in which the application development tools are provided. The development is hosted by the public cloud company and provided to clients via gateway software installed on the client computers via a portal website where clients log in to access the development tools.
Payment of Services
Public cloud typically uses the pay-as-you-go model. A client is therefore billed for the allocated instances which may be rounded up on a hour-by-hour basis. However, you may find some cloud services that are offered for free up to a certain quota, beyond which the client starts to pay. The online storage company, Dropbox uses this model.
Advantages of Public Cloud Computing
The advantages of using public clouds for computing services are so many. Notably among the advantages is the immense cost saving that can be done. Requisition of computer hardware and software is one expensive affair. Maintaining the setup can also prove to be costly in the long run. This is easily overcome by using a public cloud.
Other benefits of the public cloud are scalability to meet your precise needs, reliability, geographical location independence, and flexibility is also provided.