“It’s in the Cloud…” The Cloud has become a go-to word in computing across all levels of users, even my septuagenarian neighbour, who doesn’t even own a computer. Although she does have a smart phone and a smart TV. Trouble is ‘the Cloud’ is actually several types of cloud.
Cloud Computing existed as far back as the 1950’s. Mainframe computers used to connect to vast numbers of dumb terminals. Some of those terminals had remote access from sites away from the mainframe data centre. On all of the network diagrams, anything that went off-site from the mainframe was show connecting via a fluffy cloud indicating a private or public network including dedicated data lines and the public phone system for dial-up.
That cloud is now bigger, fluffier and, err, cloudier.
A cloud is an array of computers that connected together to operate as a single ecosystem. It will include servers of different types doing the authentication, computation, delivey of content or services and plenty of data storage. Hence clouds are configured to offer one or more services such as data storage, content delivery, or applications so that users can access these services remotely.
The user doesn’t have to know anything about the setup, operation or maintenance of the cloud or anything about how the services work – they just work. Users only have to ship requests up and down the connecting to the cloud, either sending data, retrieving data and maybe having something done to data in the servers in the cloud before getting it back.
Types of Cloud
Clouds are typically classified as deployment or service.
Deployment clouds fit into four categories:
Private Clouds are controlled and used by a single entity or organization, just not on their premises. Often the organisation has many remote sites or workers needing to tap into a centralised private cloud secured for that organisation’s activities. The organisation might manage and operate it; more likely it is contracted out to a third party to operate and maintain.
Public Clouds are open to the public, in so far as there are multiple levels of secure and open access depending on the type of services being offered. It may be a genuinely public service such as a network of public libraries or a commerical service such as cloud storage provider Dropbox.
Hybrid Clouds are a combination of private and public clouds where multiple clouds join together to share services or provide them to public and private users.
Community Clouds are private clouds whose services are shared amongst multiple entities or organizations, with common activities or types of user. Certain public bodies in different jurisdictions but in the same sector might be an example; joint academic programs across university departments and industry might be another.
Service Clouds currently fit into three main categories and many sub-categories further cloud services evolve:
Infrastructure-as-a-Service (IaaS) is the provision of computing resources such as server hardware, networking bandwidth, or network management itself. These are all infrastructure components, the cloud being a vehicle for whatever customers want to run on it. One example is Amazon’s web services., with Microsoft Azure being another. Oracle, IBM and Google offer infrastructure services.
Platform-as-a-Service (PaaS) describes an environment that users can use to develop software; they don’t want to manage either infrastructure, hardware or operating software, just develop products in a managed environment.
Software-as-a-Service (SaaS) is growing more common. Here, users gain access to applications so they don’t need to install and maintain copies locally and can access them remotely from anywhere. Office-365 and Gmail are leading examples.
That’s how to think about The Cloud – or as it turns out, lots of different clouds providing specific services for specific purposes to specific people and organisations. AJS