ONLINE STUDY MATERIAL (COMPUTER SCIENCE)

ONLINE STUDY MATERIAL CLASS XII

Computer Science Sample Paper 2015

Computer Science Sample Paper 2015 from Poonam Chopra

CLOUD COMPUTING

1. Cloud Computing	Cloud computing is an Internet based computing where virtually shared servers provide software, Infrastructure , platform , devices and other resources and hosting to customers on a pay-as-you-use basis.
2. Front end	The front end of the cloud computing system comprises the client’s device and some applications are needed for accessing the cloud computing system.
3. Back End	Back end refers to the cloud itself which may encompass various computer machines, data store systems and servers.
4.Infrastructure as a service (IaaS) or Hardware as a service(HaaS)	A model in which an organization outsources the equipment used to support operations including memory (storage space ) , hardware , virtual servers(server space) , databases and networking components.
5. Platform as a Service (PaaS)	Platform as a Service (PaaS)supplies all the resources  required to build applications and services over the internet, without having to download or install software.
Hybrid Cloud	A hybrid cloud is essentially a combination of at least two clouds , where the clouds included are a mixture of public, private or community clouds
Public Cloud	A public cloud can be accessed by any subscriber with an Internet connection and access to the cloud space.
Private cloud	Private cloud is the offering that arranges cloud computing on private networks. It consists of applications or virtual machines in a company’s own set of hosts.
Community cloud	A community cloud is shared among two or more organizations that have similar cloud requirements.

Question/ Answers:

1. What is cloud computing?

Ans. Cloud computing is an Internet based computing where virtually shared servers provide software, Infrastructure , platform , devices and other resources and hosting to customers on a pay-as-you-use basis.

2. What are the major components of cloud computing?

Ans. Clients , data center , and distributed servers.

3. Name companies which provide services in cloud computing.

Ans. Gmail, Yahoo, Hotmail, Orkut , Amazon and Microsoft.

4. What type of cloud services are provided by Amazon to public?

Ans. Amazon offers a number of cloud services ,including Elastic Compute Cloud (EC2) , Simple Storage Service (S3) ,Simple Queue Service (SQS) and Simple DB.

5. State two benefits of cloud computing.

Ans.       A. Increased security at a much lesser cost. B. Easy to maintain

6. State some characteristics of cloud computing.

Ans. Characteristics :

• ·        On demand self service by consumers
• ·        Broad access via network
• ·        Resource pooling of physical and virtual resources
• ·        Rapid scaling of capacity
• ·        Enhanced transparency of usage via metrics

7. What do you mean by the term services in cloud computing?

Ans. The term  services in cloud computing is the concept of being able to use reusable , fine grained components across a customer’s network these include:

• ·        Low barriers to entry , making them available to small businesses.
• ·        Large scalability
• ·        Resource sharing
• ·        Device independence, allows users to work on different hardware.

8. Name the resources that you can rent under HaaS.

Ans. The resources are server space, network equipments, memory , CPU cycles and storage space.

9. Name two database service providers which prominently support cloud computing.

Ans. MySQL , Oracle

10. Name three service models which are associated with cloud computing.

Ans.  The three service models are:

• ·        Infrastructure as a service (IaaS) or Hardware as a service(HaaS)
• ·        Platform as a Service (PaaS)
• ·        Software as a Service SaaS

11. State one advantage of IaaS.

Ans. IaaS allows organization to avoid the large capital expenses associated with Infrastructure and data centers.

12. State one advantage of SaaS.

Ans. SaaS eliminates the capital expenses of purchasing software and its maintenance.

13. What are the major challenges in adoption cloud computing for use?

The challenges are privacy/compliance, immaturity of vendors/offerings, legacy application.

14. what are the major threats of using cloud computing?

Ans. The threats are :

• ·        Spoofing Identity (Authentication, Protect Secrets, Avoid strong private information etc.)
• ·        Tampering with data ( Authorization , Digital Signature)
• ·        Repudiation (Digital signatures, Timestamps, Secure logging, Audit Trails etc.)
• ·        Denial of Service (Strong Authentication and authorization , Quality of Service etc.)

ONLINE STUDY MATERIAL

ONLINE STUDY MATERIAL