In this first post, we learn the fundamental basics of Cloud Computing, cloud characteristics and its advantages, different cloud implementation models, major cloud services providers in current market and different types of Cloud services offered by them. 

Below topics will be covered in this post

  1. What is Cloud Computing
  2. Advantages of Cloud Computing
  3. Different Types of Cloud Services
  4. Different Types of Cloud Delivery Models
  5. Characteristics and Features of Cloud Computing

Types of Cloud Services

Cloud service models are characterized by the term as a Service and are accessed by many types of devices, including web browsers, thin clients, and mobile devices. As cloud computing has grown in popularity, several different models and deployment strategies have emerged to help meet specific needs of different users.

Cloud Computing Services

Each type of cloud service, and deployment method, provides different levels of control, flexibility, and management for the users. Understanding the differences between these services & deployment strategies will help users decide what set of services is right for their needs. There are three primary service types

Infrastructure as a Service (IaaS)

  • It is the basic building blocks for cloud IT and typically provide access to networking features, computers (virtual or on dedicated hardware), and data storage space.
  • Infrastructure as a Service provides the highest level of flexibility and management control over IT resources and is most similar to existing IT resources that many IT departments and developers are familiar with today.
  • The cloud consumer purchases a basic computing hardware platform and can build their solutions on top of that. The consumer does not manage or control the underlying cloud infrastructure  such as physical servers, SSD disks, networking routers/switches etc but has control over operating systems, storage, deployed applications; and possibly limited control of select networking components (e.g., host firewalls). 
  • IaaS is the commonly and widely used service than the other cloud services. This will give maximum control over the IT infrastructure and users can build their own networking and security control as needed.

Platform as a Service (PaaS)

  • Platform as a Service sits on top of the IaaS and users will have less control over underlying when compared with IaaS.
  • The consumer of this service does not manage or control the underlying cloud infrastructure including network, servers, operating systems, or storage, but has control over the deployed applications and application hosting environment configurations.
  • Platform as a Service offers the compute and operating systems as a service and allows customers to install their applications on the Cloud platform.
  • The cloud provider takes responsibility up to the operating system level, including all hardware and OS software. The consumer can deploy their applications quickly without having to purchase and install their own servers and associated equipment.
  • This service removes the need for organizations to manage the underlying infrastructure and allow IT teams to focus on the deployment and management of their applications.
  • This helps IT teams to be more efficient as they don’t need to worry about resource procurement, capacity planning, software maintenance, patching, or any of the other undifferentiated heavy lifting involved in running applications, thus allowing for rapid deployment of applications.

Software as a Service (SaaS)

  • SaaS sits on top of the PaaS and the consumer of this service does not manage or control the underlying cloud infrastructure including network, servers, operating systems, storage, or even individual application capabilities.
  • The Software as a Service (SaaS) model is where the customer of the service accesses application software that is owned and controlled by the cloud company that has complete responsibility for management and support of the application. Some best examples are gmail, dropbox etc.
  • All networking, processing, storage, and applications are offered as a service in this model. Business applications are good examples of SaaS and can include customer relationship management, enterprise resource planning, human resources, payroll, and software development applications. Hosted applications such as email or calendars that are accessible from a browser are examples of SaaS. 
  • The service allows even small to medium-sized businesses to implement advanced technologies at a reasonable metered cost. New features can be quickly implemented, and there is no need for a staff to manage these communication services since the SaaS cloud provider takes responsibility.

Many cloud service providers offer more descriptive terms in their marketing and sales offerings, including Communications as a Service (CaaS), Anything as a Service (XaaS), Desktop as a Service (DaaS), and Business Process as a Service (BPaaS), to name a few of the additional offerings. However, all of these new services fit into either SaaS, IaaS, or PaaS.

Communications as a Service (CaaS)

  • This Service offers hosted voice, video conferencing, instant messaging, email, collaboration, and all other communication services that are hosted in the cloud.
  • These outsourced corporate communication services can support on-premise or mobile users accessing the applications hosted in the cloud.  Another common term for this service is Unified Communications as a Service (UCaaS).

Anything as a Service (XaaS)

This service can be described as offering complete IT services as a package. Anything as a Service is the combination of the services described in this post. It is a very broad term that is a catchall of the various service offerings.

Desktop as a Service (DaaS)

  • This service offers virtual desktops that is hosted in the cloud and accessed by desktop computers, laptops, tablets, and phones as well as any thin client solution.
  • This solution is sometimes called VDI, which stands for Virtual Desktop Infrastructure.
  • All desktop applications are hosted in the cloud and can consist of any type of application such as spreadsheets, word processing, and any other common application.
  • The DaaS provider manages all maintenance and configurations as well as licensing and version updates. 

Business Process as a Service (BPaaS)

  • This service is a specialized area that outsources many of a company’s day-to-day operations such as inventory, shipping, supply chain, finance, and other services to the cloud.
  • BPaaS is similar to SaaS except that it focuses specifically on applications that support a company’s business operations.
  • This allows for small and medium-sized businesses to access sometimes very expensive applications from a BPaaS service provider that pools its resources and allows for economies of scale in providing these services.


Do you know What is Disaster Recovery as a Service (DRaaS) is ?

Accountability and responsibility based on service models

When moving to the cloud, a company experiences a large shift in responsibilities and accountability that must be defined in service agreements. Service level agreements (SLAs) define who is accountable for what and who has ownership of responsibility for each part of the offered service. This can be very complex because many different models and responsibilities are defined.


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Cloud Solutions Architect with more than 10 years of experience in designing & deploying application in multiple cloud platforms. Owner of and tech blogs. Email me if you are interested in writing tech articles.