A Basic Description of Cloud Computing
Many different definitions of cloud computing exist, and entities deploy several different types of cloud computing to meet their specific needs. Based on the variety of definitions provided in the next section, the definition of cloud computing varies according to the perspective of the entity providing the description. Cloud service providers and other computing services providers (e.g. managed cloud services), describe cloud computing in different contexts, each according to their own business offerings.
Cloud Computing –Definitions
Based on the variety of definitions provided in this section, the definition of cloud computing varies according to the perspective of the entity providing the description. Cloud service providers describe cloud computing in different contexts, each according to their own business offerings. However, all of them agree that cloud computing requires internet service, even for onsite private clouds (see discussion on private clouds in the next section).
Dictionary – Internet-based computing in which large groups of remote servers are networked to allow sharing of data-processing tasks, centralized data storage, and online access to computer services or resources.
Microsoft Azure – Simply put, cloud computing is the delivery of computing services—servers, storage, databases, networking, software, analytics, intelligence and more—over the Internet (“the cloud”) to offer faster innovation, flexible resources, and economies of scale.
Amazon – Cloud computing is the on-demand delivery of computer power, database storage, applications, and other IT resources through a cloud services platform via the internet with pay-as-you-go pricing.
TechTarget – Cloud computing is a general term for the delivery of hosted services over the internet. Cloud computing enables companies to consume a computer resource, such as a virtual machine (VM), storage or an application, as a utility — just like electricity — rather than having to build and maintain computing infrastructures in-house.
Types of Cloud Computing
When we consider the topic ‘types of cloud computing’, we need to address cloud computing infrastructure and cloud services. In this section, we address cloud computing infrastructure and related management topics. In the next section, we address cloud computing services.
The NIST (National Institute of Standards and Technology) defines types of cloud computing in terms of cloud computing infrastructure as follows:
Private Cloud – The cloud infrastructure is operated solely for an organization. It may be managed by the organization or a third party and may exist on premise or off premise.
Community Cloud – The cloud infrastructure is shared by several organizations and supports a specific community that has shared concerns (e.g., mission, security requirements, policy, and compliance considerations). It may be managed by the organizations or a third party and may exist on premise or off premise.
Public Cloud – The cloud infrastructure is made available to the general public or a large industry group and is owned by an organization selling cloud services.
Note (comment not from NIST) – Private clouds dedicate infrastructure to a single client, most often located at the client’s location (onsite). The difference between private onsite cloud and traditional NOC is that the private cloud uses virtualization technology to manage resources, similar to that used with public clouds. In some cases, businesses outsource private cloud infrastructure and services to a cloud vendor, operating at a remote (vendor) location.
Hybrid Cloud – The cloud infrastructure is a composition of two or more clouds (private, community, or public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting for load-balancing between clouds).
You can learn more about the different uses of the various types of hybrid cloud computing in greater detail in the CIS Blog post 5 Ways Hybrid Cloud Can Benefit Business.
Cloud Computing Services
We most often refer to cloud computing services as ‘hosted services’, meaning vendor provided services for remote (vendor owned) server networks. However, some vendors also supply hosted services to infrastructure located at the client’s site. In this situation, the client or the vendor may own the infrastructure. Hosted ‘on-site’ services commonly include the use of virtualization software to distribute computing power and other computing resources efficiently.
Managed cloud computing spans a wide range of services, several of which we describe briefly below.
Hosted Infrastructure – Sometimes termed ‘IaaS’ (Infrastructure as a Service), hosted infrastructure refers to vendor owned hardware, provided to clients for a consumption-based fee. The vendor owned hardware resides remotely from the client’s location. The vendor owned and maintained servers store customer data and/or run hosted applications.
Hosted Applications – Sometimes termed ‘SaaS’ (Software as a Service), hosted applications run on vendor owned servers. The software interfaces with applications residing on client endpoints.
Disaster Recovery – The cloud provides an excellent platform for Disaster Recovery services. The remote location of the servers provides a barrier between a back-up database on onsite servers. This helps reduce the risk of malicious code on the client’s network from contaminating tornado, hurricane, flood, fire), the back-up data is not affected and disaster recovery can be complete and quickly deployed.
Cloud Benefits and Considerations
You can read more about cloud computing benefits and other cloud computing considerations from a CIS Blog post Get a New Server or Move to the Cloud.
CIS’ cloud solutions include elite cloud migration services, service monitoring and reporting, application hosting, and more. Refer to CIS Managed Cloud Services to learn more.