2.2 Virtualization and Cloud Computing Concepts

Cloud Models

IaaS = infrastructure as a service - you will be managing the system, data security, software installation - cloud service only provides the hardware for you

SaaS = software as a service - on demand software you simply login and use - no need to maintain the application or installation

PaaS = platform as a service - no servers, no software, no maintenance - usually hosted with a third party, they give you the building blocks

XaaS = anything as a service - any type of sevice provided in cloud - pay for what you're using

Edge and Fog Computing

Edge computing = practice of processing data as close as possible to the location where it is generated or needed - it pushes computational resources and data storage closer to the "edge" of the network, which can be IoT devices, sensors, or user devices. - no latency, no network requirement - increased speed and performance, process where the data is, instead of processing in the cloud - by processing data locally, it minimizes the delay caused by sending data to a centralized data center or cloud server - used in systems where log latency is crucial

Fog computing = an extension of edge computing that adds a layer of computing resources and intelligence between edge devices and centralized cloud data centers. The "fog" represents the intermediate layer - edge devices send data to nearby fog nodes, which can be gateways or small data centers - preprocess data, perform analytics, and make decisions locally - filter and process data before forwarding relevant information to the cloud

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Designing the Cloud

Virtualization = running many different operating systems on the same hardware - each application instance has its own operating system - adds overhead and complexity

Application containerization container = contains everything you need to run an application - isolated process in a sandbox - lightweight, uses the host kernel - secure separation between applications

Monolithic application = each component and its associated components must all be present for code to be executed or compiled and for the software to run - multiple components are combined into one large application - application contains all decision making process like user interface, busines logic, data input/output

Microservice architecture = uses APIs which breaks down one single service into many different microservices - scalable, resilient, higher security

Serverless architecture = an approach to software that allows developers to build and run services without having to manage the underlying infrastructure - applications are separated into individual, autonomous functions - removes the operating system from the equation

Transit gateway = router in cloud which connects multiple VPCs (virtual private cloud) together

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Infrastructure as Code

IaC is an approach to managing and provisioning computing infrastructure through code and automation scripts, rather than manual configurations. e.g. Terraform, AWS CloudFormation

Software defined networks = innovative approach to network management that uses software-based controllers or application programming interfaces (APIs) to communicate with the underlying hardware infrastructure and direct traffic on the network. - SDN separates the control plane (manages traffic) from the data plane (forwards traffic), enabling dynamic and programmable network management