Module 2.6- Virtualisation & Cloud Technologies

Question 1

Virtualisation

Answer 1

• a technology that allows you to create virtual versions of physical hardware, e.g. servers, storage devices, or even networks, within a single machine or across multiple systems
• allows multiple OSs and applications to run on the same physical hardware

Question 2

Hyperviser (Key Feature)

Answer 2

• a software that virtualisation relies on, and it sits between the physical hardware and the virtual machines (VMs); manages the VMs, allocating resources like CPU, memory, and storage
• Type 1 hypervisors- these run directly on the hardware, bare metal, and include solutions like VMware ESXi or Microsoft Hyper v
• Type 2 hypervisors- these run on top of an existing OS, like Oracle VirtualBox or VMware Workstation
• Virtual machines (VMs)- these are individual OSs, e.g. Windows or Linux, running on the virtualised hardware; each VM operates independently, even though it shares physical resources with other VMs

Question 3

Resource Efficiency (Key Feature)

Answer 3

• allows you to use hardware more efficiently by running multiple VMs on a single physical machine; this reduces hardware costs and maximises resource utilisation
• e.g. instead of running ten physical servers in a data center, each running a single application, virtualisation allows you to run ten VMs on a single physical server
• each VM can run a different OS or application all while sharing the same underlying hardware

Question 4

Cloud Computing

Answer 4

• refers to the delivery of computing resources such as servers, storage, databases, networking, software over the Internet
• instead of owning and maintaining physical hardware, you can rent resources on demand from a cloud service provider e.g. Amazon Web Services, AWS, Microsoft Azure, or Google Cloud

Question 5

Key Features

Answer 5

1) on demand resources- allows users to access resources when needed, scaling up or down based on demand; you only pay for what you use

2) public cloud- resources are provided by third party providers e.g. AWS, Azure, and Google Cloud, and shared across multiple users

3) private cloud- resources are dedicated to a single organisation, either hosted internally or by a third party provider

4) hybrid cloud- combines public and private cloud elements, allowing data and applications to move between the two as needed; service models, cloud computing is delivered in different models

Question 6

Key Features

Answer 6

5) infrastructure as a service (laaS)- provides virtualised computing resources, VMs, storage, networking

6) Platform as a service (PaaS)- delivers a platform for developers to build applications without worrying about the underlying infrastructure

7) Software as a service (SaaS)- delivers software applications over the Internet, eliminating the need to install or manage software on local machines

• e.g. if you use Google Drive to store files or Microsoft Office 365 for document editing, you’re using SaaS, software as a service. If you rent virtual machines from AWS to host a website, you’re using IS infrastructure as a service

Question 7

Virtualisation (Key Differences)

Answer 7

• you control and own the physical hardware, but you create virtual environments on top of it
• you manage both the physical server and the virtual machines running on it
• a business running virtual machines on its own servers is using virtualisation
• typically takes place on premises in your own data center or IT environment
• since you own the hardware, there’s an upfront capital expenditure, CapEx, for purchasing servers and networking equipment; however, virtualisation helps reduce operational costs by optimising hardware usage
• with virtualisation, you’d need to invest in physical servers regardless of how often they’re used

Question 8

Cloud Computing (Key Differences)

Answer 8

• physical infrastructure is managed by a third party provider such as AWS or Azure
• you don’t own or manage the hardware, and you only manage the virtual resources you’ve rented
• a business using VMs rented from AWS or Azure is using cloud computing
• cloud resources are typically located off premises and accessed over the Internet
• operates on a pay as you go model- you’re billed based on the resources you use, turning what would normally be capital expenses into operational expenses, opex
• e.g. in cloud computing, if you need to host a website temporarily, you can rent a virtual server for a short time and only pay for the resources you use

Question 9

Scalability

Answer 9

• scaling requires purchasing and configuring additional hardware to host more virtual machines
• Cloud computing is highly scalable as you can instantly provision or deprovision resources with just a few clicks- the cloud provider handles scaling, meaning you don’t need to invest in additional hardware
• e.g. during peak business hrs, an ecommerce website might need additional processing power to handle the increased traffic- cloud computing allows you to scale up temporarily and scale down after the traffic decreases

Question 10

Virtualisation in the Cloud

Answer 10

• important to note that cloud computing often uses virtualisation under the hood- Cloud providers like AWS and Azure use virtualisation to offer services like virtual machines, which are rented out to customers
• e.g. when you spin up an EC2 instance in AWS, you’re essentially using a virtual machine that runs on virtualised hardware in the cloud provider’s data centre
• without virtualisation, cloud providers couldn’t offer scalable, flexible resources in the way they do

Question 11

Advantages of Virtualisation

Answer 11

• better hardware utilisation- multiple VMs can share the same physical server, maximising hardware usage
• isolation- each VM operates independently, meaning one can fail without affecting others
• cost efficiency- reduces the need to purchase as many physical machines

Question 12

Use Cases

Answer 12

1. Testing and development- developers can create multiple test environments on a single server; server consolidation, running multiple applications on fewer physical servers, advantages and use cases of cloud computing advantages, scalability, instantly add or remove resources as demand changes
2. Cost savings- no need to invest in physical hardware; only pay for what you use
3. Accessibility- access resources from anywhere with an Internet connection
4. Web hosting- hosting websites or applications without needing to maintain physical servers
5. Data backup and recovery- storing backups in the cloud ensures data safety and accessibility from anywhere
6. SaaS applications- using software like Google Workspace or Microsoft Office 356 directly through the cloud

Question 13

Summary

Answer 13

• choosing between virtualisation and cloud- in summary, virtualisation is a key technology that helps you manage and maximise your on premises hardware
• while cloud computing is a service model that delivers scalable resources over the Internet, often using virtualisation under the hood
• deciding which one to use depends on your organisation’s needs for control, scalability, cost, and infrastructure