CP2 Computing January 2009

[1]	A low cost airline sends emails to customers advertising flights for sale.
(a)	Give two reasons, apart from speed of delivery and cost, why the airline may prefer to use email for this communication instead of using conventional post.	[2]
	using an address list, the same email can be sent to a large number of people multimedia attachments such as video clips can be sent
(b)	Describe one problem that may arise from using email in this way.	[1]
	a virus may be spread

2.(a)	Draw a diagram of a bus network.	[1]

(b)	Draw a diagram of a star network.	[1]
	xxx
(c)	Give one advantage of using a star network rather than a bus network.	[1]
	reliable - if one workstation goes down, the rest of the network is unaffected.
(d)	Describe two advantages of network computers compared with standalone computers.	[2]
	hardware can be shared eg. printer workstations on the network can communicate (send emails or files)

3.	Many cars are now fitted with satellite navigation systems. The car's destination is input and the driving directions are output.
(a)	One method of output is a screen display. looking at the screen while driving would be distracting for the driver. What other method of output would be more suitable?	[1]
	speech synthesis (voice output)
(b)	Explain why voice input would be a suitable method of input for this device.	[1]
	the driver does not have to use hands, or look at the device and can carry on driving safely.
(c)	Describe two situations where voice input may not be recognised by the device.	[2]
	local regional accents may not be recognised illness such as a cold may cause a voice to be unclear

4.	A secondary school has a file server with a 500 gigabyte hard disc.
(a)	Describe in detail a suitable strategy for backing up the data stored on the file server.	[2]
	Use another high-capacity external hard disc drive... ...and copy the contents of the current drive onto it every night.
(b)	Describe in detail a suitable strategy for restoring this data after a failure.	[2]
	Store the backup drive off-site, away from hazards Copy the contents back onto the original drive.

5.	An optician collects customer's details during their first visit. These details are stored on paper in files.
	The number of customers is increasing and the optician finds that amending customer details is extremely time consuming. Describe two other possible problems with the current paper-based system and describe how a computerised database system could solve these problems.	[4]
	Searching for a client's detail takes a long time.... ...a computerised database has high-speed search facilities (queries) Clients details are getting lost... ...the database can be backed up regularly to prevent data loss.

6.	Validation checks are carried out on customer data entered into a computer at a car rental company.
(a)	What is the purpose of validation checks?	[1]
	checks that the data is reasonable / sensible
(b)	One item of data being entered is the age of the car driver. Name a suitable validation check and describe how this check would detect an invalid age being entered.	[2]
	A range check could be used ... ...to check the age is between defined limits eg between 18 and 80

7.	The Conifer Hotels group has hundreds of hotels throughout the world. Guests of Conifer Hotels have loyalty cards that earn points for every stay at a participating hotel. Guests can access their loyalty card accounts on-line using the Internet. They are able to view statements and use points to claim free hotel nights. These accounts could be subject to malicious or accidental damage.
(a) (i)	Describe what is meant by the term malicious damage and explain how Conifer hotels could prevent malicious damage to the data stored in these accounts.	[2]
	Intentional altering or deleting of data Eg by hackers Use usernames and passwords to access the data
(ii)	Describe what is meant by the term accidental damage and explain how Conifer Hotels could prevent accidental damage to the data stored in these accounts.	[2]
	Unintentional alteration of data by mistake Make important data read-only.
(b)	Conifer Hotels comply with the Data Protection Act by ensuring that guests data is up to date and accurate, held securely and held for no longer than necessary. Describe three other ways in which Conifer Hotels must operate in order to comply with the Data Protection Act.	[3]
	Data must be obtained fairly and lawfully Data must only be used for the stated purpose They must allow customers to check their personal data to see if it is correct, and change it if it is not.

8. (a)	An operating system provides an interface between the hardware and the user and manages system resources.
(i)	Describe three functions of an operating system from a user's point of view.	[3]
	Loads and runs programs Maintains security - only allowing authorised users to have access to the computer system. Allows users to copy or delete files and folders.
(ii)	Name three resources which an operating system would manage.	[3]
	Backing storage devices such as hard drives/USB memory sticks Memory (RAM) Input and output from input or output devices such as keyboard/mouse
(b)	A theatre sells tickets using real time transaction processing. Describe how real time transaction processing works in this case and explain why it is the most suitable mode of operation	[2]
	As soon as the computer receives the data, it is processed and data is updated. Prevents double-booking of tickets.

9. (a)	Records within a file can be fixed length or variable length. Describe the difference between fixed and variable length records, giving one advantage of using a variable length record.	[3]
	Fixed length records - all records are the same size (number of bytes) Variable length - the records are different sizes, with separators between each field. Advantage of variable length - file size will be smaller so faster to download or transmit files.
(b)	A household gas supplier takes readings from customers' gas meters every three months. The current meter reading for each customer is stored in a transaction file. Customer details are stored in a master file.
(i)	Why is serial file organisation the most suitable method for the transaction file?	[1]
	There is no order and records can be added to the end of the file as they occur.
(ii)	Why is sequential file organisation the most suitable method for the master file?	[1]
	The records can be accessed in sorted order for the update process.
(iii)	Explain how the transaction file is used to update the master file when producing the gas bills.	[2]
	A new master file is created Each transaction record in turn is either copied to the new file, or used to update the corresponding record in the master file which is then saved in the new file.

10.	Explain what is meant by each of the following computer terms:
(a)	address bus;	[1]
	The path down which address data is sent
(b)	byte;	[1]
	8 binary digits (bits)
(c)	word;	[1]
	The number of bits that a processor can process at a time.
(d)	disk cache memory.	[1]
	An area of memory that stores data that has been read from a hard disc.

11.	In the following question, additional credit ( up to 3 marks) will be given if your answer demonstrates skill in written communication.
	A computer software company has been asked to produce a commercial web for a customer. The company employs a team of software developers who will be provided with the necessary hardware and software and will work from home and will have access to the company intranet.
	From the company perspective describe the benefits of the developers working from home.
	From the developers' perspective describe the drawbacks of working from home.
	Explain why the software developers would find the company's intranet useful.	[8+3]
	The company would not have to provide office space for the developers and would save money on electricity bills as they would not have to provide lighting or heating. They also would save money as they do not need to provide other facilities such as canteen food, toilets or car parking. The web project may also be completed faster because the developers could work in a more relaxed atmosphere in their homes, and work the hours they want to. There may a certain amount of distraction in the home environment such as small children or pets, and motivation to do the work may be difficult to achieve. There would also be a lack of social contact with fellow workers. The developers could use the company's intranet to keep in touch with the latest news and developments of the company, and they could use it to inform fellow workers about progress of the web. The intranet could also be used to communicate with other workers and share ideas about the web project.