CCSK Domain One Flashcards
In Cloud Computing what do the terms abstraction and orchestration mean ?
We abstract resources from the underlying physical infrastructure to create our pools and use orchestration to coordinate carving out and delivering a set of resources from the pools to the consumers.
In Cloud computing what do the terms segregation and isolation mean ?
Segregation allows the cloud provider to divvy up resources to the different groups and isolation ensures that they cant see or modify each others assets. Multitenancy doesnt only apply across different organisations, it is also used to divvy up resources between different units in a single business organisation.
What are the essential characteristics of cloud computing ?
Broad Network Access, Rapid Elasticity, Measured Service, On Demand Service and Resource Pooling
What are the three service models of cloud computing ?
SaaS, PaaS, IaaS
What are the four deployment models of cloud computing ?
Public, Private, Hybrid, Community
How does IaaS work under the hood ?
A series of physical servers each run two components - a hypervisor and the management/orchestration software to tie in the the servers and connect them to the compute controller. A customer asks for an instance of a particular size and the cloud controller determines which server has the capacity and allocates an instance of the requested size.
The controller then creates a virtual hard drive by requesting storage from the storage pool, and connects it to the appropriate host server and instance over the network. Networking including virtual network interfaces and addresses is also allocated and connected to the necessary virtual network.
The controller then sends a copy of the server image to the virtual machine boots it and configures it. This creates an instance running in a VM with virtual networking and attached storage - once completed the metadata and connectivity information is brokered by the cloud controller and available to the consumer who can now connect to the instance and log in.
How does PaaS work under the hood ?
PaaS adds an additional layer of integration with application development frameworks, middleware capabilities and functions such as databases, messages and queuing. These services allow developers to build applications on the platform with programming languages and tools that are supported by the stack.
In PaaS the cloud user only sees the platform, not the underlying infrastructure.
How does SaaS work under the hood ?
Many SaaS providers build on top of IaaS and PaaS due to increased agility, resiliency, and potential economic benefits. Modern cloud applications use a combination of approaches sometimes across different cloud providers. Many also tend to offer public APIs for some or all functionality.
What is infrostructure ?
Data and Information, content in data stores
What is applistructure ?
Applications that are deployed onto the cloud
What is metastructure ?
The protocols and mechanisms that provide the interface between the infrastructure layer and the other layers. Contol Plane
What is infrastructure ?
The core components of a computing system compute, network and storage
When do you select the cloud provider ?
Immediately after the requirements are determined and before defining the architecture
