Cloud Computing Architecture Interview Questions And Answers

Vertical scale up provides more resources to a single computational unit, whereas horizontal scale out provides additional computational unit and run them in parallel.
Vertical scale up provides a provision to move a workload to other system that doesn’t have workload, whereas horizontal scale out split the workload among various computational units.
Vertical scale up doesn’t have a database partitioning concept, whereas horizontal scale out provides the database partitioning.

There are lots of tools that are being used by the cloud architecture to provide the performance transparency and automation. The tools allow the user to monitor report and manage the cloud architecture. It also allows them to share the applications using the cloud architecture. Automation is the key component of cloud architecture as it provides the services to increase the degree of the quality. It brings the capacity on demand and allows the requirements of the user to be met.

Cloud architecture is a software application that uses on demand services and access pool of resources from the cloud. Cloud architecture act as a platform on which the applications are built. It provides the complete computing infrastructure and provides the resources only when it is required. It is used to elastically scale up or down the resources according to the job that is being performed.

Cloud architecture provide large pool of dynamic resources that can be accessed any time whenever there is a requirement, which is not being given by the traditional architecture. In traditional architecture it is not possible to dynamically associate a machine with the rising demand of infrastructure and the services. Cloud architecture provides scalable properties to meet the high demand of infrastructure and provide on-demand access to the user.

The three differences that make cloud architecture in demand are:
1. Cloud architecture provides the hardware requirement according to the demand. It can run the processes when there is a requirement for it.
2. Cloud architecture is capable of scaling the resources on demand. As, the demand rises it can provide infrastructure and the services to the users.
3. Cloud architecture can manage and handle dynamic workloads without failure. It can recover a machine from failure and always keep the load to a particular machine to minimum.

Cloud architecture uses simple APIs to provide easily accessible services to the user through the internet medium.
It provides scale on demand feature to increase the industrial strength.
It provides the transparency between the machines so that users don’t have to worry about their data. Users can just perform the functionality without even knowing the complex logics implemented in cloud architecture.
It provides highest optimization and utilization in the cloud platform

1. Zero infrastructure investment:
Cloud architecture provide user to build large scale system with full hardware, machines, routers, backup and other components. So, it reduces the startup cost of the business.

2. Just-in-time Infrastructure: It is very important to scale the infrastructure as the demand rises. This can be done by taking cloud architecture and developing the application in the cloud with dynamic capacity management.

3. More efficient resource utilization: Cloud architecture provides users to use their hardware and resource more efficiently and utilize it in a better way. This can be done only by applications request and relinquish resources only when it is needed (on-demand).

Cloud architecture mainly focuses on quality of service. It is a layer that manages and secures the transmission of the resources that is being acquired by on-demand access. Quality of service is being maintained such that it increases the performance, automated management, and support services. Cloud architecture provides easy to use methods and proper ways to ensure the quality of service. It is represented by a common cloud management platform that delivers many cloud services based on the same foundation.

Cloud architecture defines three roles:
Cloud service consumer: it is used to provide different services to the consumer on demand.
Cloud service provider: here provider provides the services to meet the requirements of the user by monitoring the traffic and demands that are coming.
Cloud service Creator: here creator is used to create the services and provide the infrastructure to the user to use and give the access to the resources.

The roles that are being defined can be performed by one person or it can be performed by many people together. There can be more roles defined depending on the cloud architecture and the complexity with which it will scale.

The major building blocks of cloud architecture are:
1. Reference architecture: it is used for documentation, communication, designing and defining various types of models
2. Technical Architecture: defines the structured stack, structure the cloud services and its components, show the relationship that exist between different components, management and security
3. Deployment Operation Architecture: it is used to operate and monitor the processes and the services.

It provides the consumer with hardware, storage, network and other resources on rent. Through this consumer can deploy and run software using dedicated software. This includes the operating system and the applications that are associated with it.

it provides the user to deploy their software and application on the cloud infrastructure using the tools that are available with the operating system.

it provides the users the ability to run its application on the cloud infrastructure and can access it from any client device using any interface like web browser.

it provides any business process that is delivered through cloud service model using the internet and accesses the resources through the web portal.

There are lot of examples that uses cloud architecture for their applications like:
1. Processing Pipelines: uses like document processing pipelines that convert documents of any form into raw searchable text.
Image processing pipelines – create thumbnails or low resolution image
Video transcoding pipelines – convert video from one form to another online
Indexing – create an index of web crawl data
Data mining – perform search over millions of records

2. Batch Processing Systems
Systems that uses log management or generate reports.
Automated Unit Testing and Deployment Testing

3. Websites
Instant Websites – websites for conferences or events
Promotion websites

There are 5 major components of cloud architecture.
1. Cloud Ingress: provides a mean to communicate with the outside world. This can be done with the help of communication methods such as:
Queue based communications
HTTP communications
REST/SOAP
Service Bus
2. Processor Speed: processor speed is the major section on which the whole cloud architecture is based. It provides on demand resources that can be dynamically allocated to the user. It saves lots of cost and has many benefits of virtualization.

3. Cloud storage services: cloud services provide means to store data to user’s applications. It is used to provide services for different types of storages like: table data, files.

4. Cloud provided services:
Additional services are provided by the cloud, like data services, payment processing services, and search or web functionality services.

5. Intra-Cloud communications: it provides a way to communicate with other systems that are using cloud architecture. Providers usually provide services so that one user can communicate easily with another user by being on cloud.

There are four phases that basically gets involved in the cloud architecture:
1. Launch phase: it launches the basic services and makes the system ready for communication and for application building
2. Monitor phase: it monitors the services that is being launched and then manages them so that on demand the user will be able to get what he wants.
3. Shutdown phase: it shutdown the services that are not required first and after all the services gets shutdown, and then it closes the system services.
4. Cleanup phase: it clean up the left out processes and services that is being either broken or didn’t get shutdown correctly.

Service oriented architecture (SOA) is an architectural style that supports service oriented methodology that is being added in the cloud architecture as a mandatory component. Cloud architecture support the use of on-demand access to resources and it provides lots of other facilities that are being found in SOA as well. SOA makes these requirements optional to use. But, to get the full functionality and more performance based efficiency there is a requirement for the mixture of SOA and cloud architecture.

There are 4 types of cloud service models available in cloud architecture:
1. Infrastructure as a service:
It provides the consumer with hardware, storage, network and other resources on rent. Through this consumer can deploy and run software using dedicated software. This includes the operating system and the applications that are associated with it.

2. Platform as a service: it provides the user to deploy their software and application on the cloud infrastructure using the tools that are available with the operating system.

3. Software as a service: it provides the users the ability to run its application on the cloud infrastructure and can access it from any client device using any interface like web browser.

4. Business Process as a service: it provides any business process that is delivered through cloud service model using the internet and accesses the resources through the web portal.

The characteristics that makes cloud architecture above traditional architecture is:
► According to the demand cloud architecture provides the hardware requirement
► Cloud architecture is capable of scaling the resource on demand
► Cloud architecture is capable of managing and handling dynamic workloads without failure

To provide the performance transparency and automation there are many tools used by cloud architecture. It allows to manage the cloud architecture and monitor reports. It also allows them to share the application using the cloud architecture. Automation is the key component of cloud architecture which helps to improve the degree of quality.

Hypervisor is a Virtual Machine Monitor which manages resources for virtual machines. There are mainly two types of hypervisors:
► The guest Vm runs directly over the host hardware, eg Xen, VmWare ESXI
► The guest Vm runs over hardware through a host OS, eg Kvm, oracle virtualbox

Cloud computing architecture refers to the components and sub components required for cloud computing. These components typically consist of a front end platform (fat client, thin client, mobile device), back end platforms (servers, storage), a cloud based delivery, and a network (Internet, Intranet, Inter-cloud). Combined, these components make up cloud computing architecture.

► Reference architecture
► Technical architecture
► Deployment operation architecture

The software-as-a-service (SaaS) service-model involves the cloud provider installing and maintaining software in the cloud and users running the software from their cloud clients over the Internet (or Intranet). The users' client machines require no installation of any application-specific software - cloud applications run on the server (in the cloud). SaaS is scalable, and system administration may load the applications on several servers. In the past, each customer would purchase and load their own copy of the application to each of their own servers, but with the SaaS the customer can access the application without installing the software locally. SaaS typically involves a monthly or annual fee.