4.1 Cloud Computing and 2.2 Networking Hardware Flashcards
What is cloud computing?
The practice of using a network of remote servers hosted on the Internet.
List some characteristics of the cloud (there are nine in total).
- High availability
- Scalability
- Vertical scaling
- Horizontal scaling
- Rapid elasticity
- Metered utilisation
- Measured services
- Shared resources
- File synchronisation
What is the definition of availability?
Percentage of uptime versus downtime.
Define scalability.
Ability to increase the number of items in a system at a linear rate or less than a linear rate
Define vertical scaling.
Increasing the power of the existing resources in the working
environment
Define horizontal scaling.
Adding additional resources to help handle the extra load being
experienced
Define rapid elasticity.
Elasticity is the system’s ability to handle changes to demand in
real time
Define metered utilisation.
Being charged for a service on a pay per use basis (most services in the cloud are done this way)
Define measured services.
Charging is based upon the actual usage of the service being consumed.
What is shared resources?
- Pooling together all the hardware to make a cloud provider
- The ability to minimise the costs by putting VMs on other servers
What is file synchronisation?
The ability to store data that can spread to other places depending on the configuration.
List the cloud deployment models (there should be six).
- Public cloud
- Private cloud
- Hybrid cloud
- Community cloud
- Multitenancy
- Single-tenancy
How does a public cloud work?
Systems and users interact with devices on public networks, such as the internet and other clouds.
Who can access a private cloud?
Systems and users that only have access with other devices inside the system.
What is a hybrid cloud?
A combination of the public and private clouds.
What is a community cloud?
A collaborative effort where infrastructure is shared between several organisations from a specific community with common concerns.
Define multitenancy.
The ability for customers to share computing resources in a public or private cloud.
Define single-tenancy.
A particular resource assigned to a single organisation.
What are the two cloud service models (with a brief definition)?
On-premise solution: All hardware, software and personnel are procured and controlled by the organisation
Hosted solution: Third-party service provider that provides all hardware and facilities needed to maintain a cloud solution
What is Virtual Desktop Infrastructure (VDI)?
Desktop OSs within a virtualised environment hosted by a centralised server or server farm.
What is a centralised model in VDI?
All desktop instances hosted on a single server/server farm
What does the server do in VDI?
Performs all the application processing and data storage
What is the hosted model/Desktop as a Service?
Maintained by a service provider and provided to the end user as a service
What is a remote virtual desktop model?
Desktop image copied to local machine prior to being utilised by end user
Name three cloud storage services.
- Cloud storage application
- File synchronisation
- Content delivery network (CDN)
What is CDN (as a cloud storage service)?
A network of servers that locates the nearest server to minimise delay or download time
What does software-defined networking (SDN) do?
Enables the network to be intelligently and centrally controlled/programmed, using software applications.
What does the OSI application layer focus on?
The communication resource requests or information about the network as a whole
What does the control layer do?
Uses the information from the applications and decides how to route a data packet on the network
What is a key feature of the infrastructure layer?
It contains the network devices that receive information about where to move the data
What is the management plane used for?
- Monitoring traffic conditions and the status of the network
- Providing a layer of abstraction between the devices and the control and data flow that happen on the network
