Cloud Computing Interview Questions – Part 1
By Kamal Jacob
Cloud computing is not just a modern buzzword, it is a technology that is powering applications for the smallest to the largest organizations in the world today. Clearly, for your career growth in the field of information technology, cloud computing holds several opportunities. In order to help you advance your career, here is a curated list of most frequently asked questions in the cloud computing interviews.
Let’s get started.
What is the difference between IaaS, PaaS, and SaaS?
Infrastructure as a service (IaaS)
IaaS (Infrastructure as a Service) is the basic model of cloud computing services. In the case of IaaS, users rely on renting the computing infrastructure, which includes servers, virtual machines (VMs), storage, networks, and operating systems. They rent these resources from a cloud service provider on a pay-as-you-go basis.
Platform as a service (PaaS)
PaaS (Platform as a Service) is a set of cloud computing services which involve providing an Internet-based environment for developing, testing, delivering and managing software applications. PaaS solutions are built to make it possible for developers to code directly on the Web and easily build a web or mobile apps. This eliminates the hassle of establishing an operating system, setting up servers, storage for code and configuration, and databases required for developing a software application. It takes care of the infrastructure requirements automatically for developers.
Software as a service (SaaS)
SaaS (Software as a service) is a cloud service delivery model where software solutions are delivered over the Internet to the users. They are typically delivered on an on-demand basis and are charged frequently on a subscription basis. In the case of SaaS solutions, the cloud service providers take care of developing, hosting and managing the software applications, their underlying platform, infrastructure, etc. They are also responsible for handling all the maintenance and management issues, security issues and for further development, releases, upgrades, and patches. In the case of SaaS, users access the applications using their browsers on their mobile or desktop computing devices.
What according to you is better - Azure or AWS?
Azure & AWS both are the dominant cloud players & both have pros & cons. Azure has the majority of market share, but AWS is still the largest cloud service provider. Both of these platforms have ample growth opportunities.
While AWS has a weak hybrid strategy, Azure is open to hybrid cloud systems. AWS has plenty & complex scale offerings which makes it hard for users to choose the best fit service, & on the other hand, Azure provides ease of transition. Sometimes, Azure has low-quality support & has less flexibility than AWS. Unlike Azure, AWS has high transfer stability. And the list goes on.
But above, all these pros, cons & your business needs, both are highly reliable cloud service providers & one must not hesitate to choose either of them as both provide its users with ingenious offerings at economical cost.
What are the various deployment types in the cloud & what are their use?
There are the following types of cloud deployments:
A public cloud is a cloud environment that is owned and operated by a third-party cloud service provider and not by the consumer of the cloud services. The third-party cloud service providers owning the public cloud deliver the computing resources such as servers, platforms, storage, databases, networks, etc. over the Internet. The consumers of cloud services are responsible for managing the resources they have a subscription to and typically, use web browsers to do so.
AWS (Amazon Web Services), Microsoft Azure, Google Cloud Platform (GCP), IBM Cloud, Rackspace are few leading public cloud service providers. However, their services, geographies and target segments are not the same despite having some common services.
Private cloud is a cloud computing deployment model where all the cloud computing resources belong to a single enterprise or business, exclusively. In terms of the physical location of the private cloud, it could be hosted at the on-premise data centers of the organization or could be hosted at the data centers owned, maintained and managed by the third-party service providers. All the computing resources in a private cloud are maintained on a private network.
As the name suggests, is a hybrid cloud model, a hybrid cloud offers a combination of public and private clouds. These private and public clouds are connected together by technology components that enable the sharing of data and applications between the two. Because data and applications can be connected between the private and public clouds, you get advantages of having great flexibility, multiple topologies for integration, more options for deployment and an increased ability to choose your workloads where they fit the best. In addition, hybrid cloud offers you better able to optimize security, performance, data residency and compliance.
What are the crucial modules of cloud architecture?
Cloud architecture comprises of components like Cloud Ingress, Processor speed, Cloud storage services, provided services, & intra-cloud communications.
What are the unique attributes of Cloud Computing?
Some unique attributes of the cloud are Elasticity, Utility type of delivery & low barrier to entry.
What is the difference between scalability and elasticity?
Scalability refers to the ability of cloud computing that allows handling of the increase in workload by increasing the amount or capacities of the resources allocated to your applications. Scalability ensures that your applications won’t suffer a poor performance even if there is a significant in load or traffic.
Elasticity is a characteristic of cloud computing that enables automated or manual commissioning and decommissioning of a large amount of resource capacity dynamically. It is measured by the speed by which the resources are becoming available on demand and the usage of the resources. Elasticity also allows the ramping down of the resources as the demand decreases.
What is the difference between scaling up and scaling out?
Scalability enables your applications to not suffer the performance degradation at the times of higher resource utilization by increasing the amount or capacities of the resources allocated for computing. It is of two types: scaling up, also known as vertical scaling and scaling out, also known as horizontal scaling.
Scaling up or vertical scaling refers to the event when you add more computing resources to the same server. For example, increasing memory or storage to the same server may be termed as scaling up.
Scaling out or horizontal scaling refers to the addition of more servers in parallel to handle more load.
What Is The Requirement Of Virtualization Platforms In Implementing Cloud?
Virtualization is a technique that allows the sharing of the same computing environment amongst multiple instances. It forms the basis of cloud computing by offering a huge computing infrastructure to a large set of users. There sare multiple platforms, such as VMWare, that provides the provision to create a private cloud and provide a bridge to connect external cloud with private cloud.
Virtualization can be achieved on your private cloud after careful consideration of the following aspects:
1. Cloud operating system.
2. Management of the service level policies.
3. Isolation at various levels, such as user level, infrastructure level, network level and data layer level. This is important to ensure in order to keep each user separate from another user.
Which services need to be negotiated in SLA’s?
Usually, auditing, logging, & regulatory compliance demand planning in the cloud systems.
How to protect data in Cloud?
Whatever service model has been chosen, needs to ensure access control, auditing, & authentication in order to provide data security requirements in the cloud.
In the next part of the interview series, we will have a look at some more important questions that are often asked during a cloud computing interview.
If you are looking to gain a 360-degree knowledge on cloud computing, do not forget to check Manipal Prolearn’s courses on cloud computing