IT1 Section A: Networks - Database systems Flashcards
what does a computer network consists of?
- a computer network consists of two or more computers and peripherals that are linked together
- peripherals= printers, scanners
what is a standalone computer?
-a standalone computer is not part of a network and can only access data files that are stored on that computer
can be data be shared or not shared on a network computer?
-data can be shared on a network computer
what are the advantages and disadvantages of a network computer?
Advantages
- hardware can be shared
- software can be shared
- data can be shared
- there is improved communications between users
- improved security
- central backup
Disadvantages
- purchasing the network cabling and file servers can be expensive
- viruses can spread to other computer throughout a computer network
- danger of hacking so procedures are needed to prevent it such as firewalls
what are the advantages of standalone computers?
- fewer hardware requirements (don’t need as much cables, routers, gateways)
- reliability of performance
- security (as it’s not as susceptible to virus)
- less ict knowledge required
what are the two types of networks?
- LAN
- WAN
describe and state what LAN stands for
- LAN (local area network)
- restricted to one room or building; connected via dedicated cables (although can be wireless)
describe and state what WAN stands for
- WAN stands for Wide Area Network
- spread over a wide geographical area; linked via public telecom systems such as telephone lines satellite link and microwave signals
give examples of WANS
- booking systems
- home banking
- bank ATMs
- National Lottery
- Stock Control
- the internet is a very large WAN
what is the internet?
-the internet (international network) is a very large number of computer networks that are linked together via telecom systems
what is the World Wide Web (WWW)?
-the WWW is a vast collection of pages in multimedia form held on the internet
what are the uses of internet?
- communicate quickly each other via VoIP (skype) and email
- share data
- use browser software to access web pages
- search for information
what are the advantages and disadvantages of the internet?
Advantages
- easy communication with other people
- a vast amount of information can be accessed
- publishing documents on the internet saves paper
- enables more people to work from home using a computer networks (teleworking)
Disadvantages
- much of the information isn’t checked and may be incorrect or irrelevant
- too much time spent on the internet could result in a lack of face-to-face interaction with others and loss of social skills
- you’re at risk of hackers or viruses damaging your computer when you go online
- large telephone bills can easily be run up
what are the developments of the internet?
- videoconferencing
- E-commerce
- Web Publishing
- Broadcasting
- Downloading
how can you access the internet?
- a browser is needed to access the internet e.g Safari, Internet Explorer
- you need an internet service provider (ISP) to connect to the internet, e.g Sky, BT, AOL
- the ISP normally provides an email address and a limited amount of web space.
- the ISP provides users with a software package that needs installing on their computer, sometimes have filters.
what is e-mail
Electronic Mail
to enable the sending and receipt of electronic mail anywhere in the world for the same cost as accessing the internet
what are the benefits of email?
-it is an accurate transcript of an exchange
-it is instant
-emails can be sent to on person or several people at once
-
what are the disadvantages of email?
- you can get spam- unsolicited email i.e junk mail
- can be abrupt
- overuse can lead to a lack of social interaction
- the recipient needs access to the internet to receive email
- viruses are easily spread via email attachments
what is FTP and what is the purpose of it?
File Transfer Protocol
- a standard set of rules to enable exchange of files over the internet (e.g downloading)
what is a search engines
- a program that searches for pages on the WWW that have a keyword the user has specified e.g Google
what is intranet? give an example and what are the benefits?
-a private internet/ closed network only accessible within the organisation
benefits:
(for a hospital) allows consultants to access privileged info from home
-allowers users to access med info that staff can not have
-reduces paper
what is extranet? give an example
- An intranet that is partially accessible to people outside of a company who must be authorised (e.g suppliers, customers) who still need a user name and password
e. g suppliers, customers etc. who still need a user name and password so they cans see their items and tracking details of items.
what is a forum/newsgroup?
an online discussion group
what is a chat room?
a chat room is where a number of users communicate about a certain topic
what do HCIs allow users to do?
HCIs allow the user to tell the computer what to do and the computer to interact with the user by giving them a response
what things have to be taken into account in the making of HCIs? expand on each factor
TASK- CAD (fast processing), Primary school (animations), Computer game (high def graphics)
USER EXPERIENCE- more experienced users what less key strokes, beginners need more
USER PREFERENCE- pull down menus; icons, commands
RESOURCES- more sophisticated HCIs require large processing power and memory
USER NEEDS- disabilities; poor eye sight etc.
ENVIRONMENT OF USE- where are they e.g on the go, in a factory
what are the types of HCIs?
- Command Line interface
- Graphical User Interface
- Voice Interface
- Graphic Devices
- Game Playing Devices
- Touch Sensitive Screens
- Biometric Devices
state the uses of Command Line interface
- expert using it to find information on network/system configuration
- writing small batch files (in DOS)
state the advantages of Command line interface
- fast to execute (run)
- don’t have to go through the menu system/ faster to enter commands
- need very little overheads (memory/processor)
state the disadvantages of command line interface
- need to know the commands
- can run slowly
state the uses of Graphical User Interface
- for a primary school child using a maths program
- setting up a profile on a games console
- customising a desktop application
- uses WIMP (windows, icons, menus and pointers)
state the advantages of graphical user interface
- makes the operation of the computer as user friendly as possible by using a high resolution graphics and pointers
- instead of typing in commands you enter them by pointing and clicking
- fun to use
- colourful and engaging
state the disadvantages of graphical user interface
- needs a powerful processor
- can run slowly
state the uses of touch sensitive devices
- in museums to allow children to gather information
- in shops to enter info at POS mobile phones to dial or display information
- buying tickets at railway stations
state the advantages of touch sensitive devices
- saves having to type, quicker to enter information as it may be in a fixed list of options
- empowering for the disabled people who may have physical disability as there is no need for a mouse and keyboard
- used in hostile environments because keyboards can get sticky
- frees staff to do other jobs
state the disadvantages of touch sensitive devices
- might not have all the options
- the screens could get dirty or damaged
- screens require recalibration
state the uses of Voice interface
- student dictating an essay directly into word processing software
- mobile phones e.g to dial the phone number of a contact
- control systems e.g to control the lights in a room
- security systems e.g to allow entry
- in car navigation systems e.g to plan route
state the advantages of voice interface
- quicker than typing
- allows people to enter text directly into a computer without using a keyboard
- can perform complicated tasks by dictation
- can empower the disabled
- uniqueness of voice print cannot be used by others q
state the disadvantages of voice interface
- have to speak slowly
- interference from background noise
- colds, soar throats may affect voice
- takes time to train the system
- similar words (homonyms) may be confused e.g to, too, two
state the uses of biometric devices
- retina scan
- Iris recognition to gain access to room, facial recognition at airports for identity
- thumbprints used for school registration systems
state the advantages of biometric devices
- accuracy
- unlike smart cards you cant easily lose a finger, eye etc.
state the disadvantages of biometric devices
- equipment is very expensive to buy
- ethical issues about schools storing biometric data
- potential misuse for biometric data e.g a staff’s dna profile could also be used to screen for various genetic diseases or other ‘undesirable traits’.
State the uses of Game playing devices
- joysticks to control a plane in a flight stimulator
- steering wheels to control a stimulation of a car
- line of motion sensors (camera tracking motion) could be used in racing
- virtual reality interface can be used in games
- Omni directional treadmill
state the advantages of game playing devices
- saves having to type, quicker to enter information/fixed list of options
- greater realism in the game playing/ more interactive
- greater accuracy/ sensitivity/ complexity in the movement
- aids fitness
state the disadvantages of game playing devices
- some people find the joysticks, controllers etc. more difficult to control than a traditional mouse
- some devices are not particularly robust and can break easily if too much force is used on them
State the Uses of Graphic devices
- often used by graphics designers and illustrators
- consists of a flat pad (the tablet) on which you ‘draw’ with a special pen
- as you draw on the pad an image is created on the computer monitor from within the application that the tablet is connected to
state the advantages of graphic devices
- it is much more natural to draw diagram with a pencil type implement (the stylus) rather than with a mouse
- a great level of accuracy can be achieved
state the disadvantages of graphic devices
- not really suitable for general selection work such as pointing and clicking on menu items
- graphics tablets are much more expensive than a mouse
what legal requirement was created that was required for employers to use?
the health and safety (display screen equipment) regulations of 1992 made it a legal requirement for employers to protect the health of workers using computers
what is RSI? what are the causes and what are the remedies?
RSI is repetitive strain injury
Causes:
-Using a keyboard which means hands are positioned at an awkward angle
-sitting for long periods at poorly organised workstation
-squeezing a mouse over long periods
Remedies:
- use ergonomic keyboards
- wrist supports
- regular breaks
what are the causes and what are the remedies of eye strain?
Causes:
- looking at the screen for a long time
- poorly sited screen
- wrong lighting in a room
Remedies:
- non-flickering screens and screen filters
- appropriate blinds
- eye tests
- eye line level with top of the screen
- regular breaks
what are the causes and what are the remedies of back problems?
Causes:
- incorrect height of chair
- sitting for long periods
Remedies:
- ergonomic
- height adjustable swivel chair
- document holders
- tilt and turn screens
- regular breaks
what are the causes and what are the remedies of stress?
Causes:
- inappropriate HCI
- hardware failure
- slow response time
Remedies:
- training
- well designed software
- appropriate hardware
what is ELF radiation? what are the causes and remedies?
ELF radiation stands for extremely low frequency
Causes:
-but monitors emitting radiation causing abnormal pregnancies
-miscarriages
Remedies:
- low emission monitors
- screen filters
what is the Code of practice?
a behaviour code for ICT users describing their responsibilities, rules for maintaining security and the penalty for misuse.
give examples of the responsibilities found in the code of practice
-relating to use of hardware and software data
give examples of the rules found in the code of practice
- only use your own user ID
- how often passwords should be changed
state the penalties found in the code of practice
- Verbal Warning
- Written Warning
- Dismissal
- Prosecution
what is the Computer Misuse Act of 1990 and what sort of crimes were made under this act?
-Act that aims to protect computer users against malicious vandalism and information theft.
Crimes made under this act were:
- Hacking
- knowingly spreading viruses
what are the three sections in the Computer Misuse Act of 1990? give examples and the penalties given for each
1.) Unauthorised access to computer material
-trying to access programs or data without permission and trying to guess password
e.g a student gains access to another student’s area
Penalty: max. six months prison and £5000 fine
2.) Unauthorised access with internet to commit or allow further offences
-accessing a computer system wanting to commit fraud or blackmail
e.g breaking into a computer system to find out secret information that could be used for fraud
Penalty: max. five years prison
3.) Unauthorised modification of computer material
-altering data or programs within a computer deliberately
e.g changing the balance of a bank account/ changing examination marks
Penalty: max. five years prison
what does the Data Protection Act 1998 cover?
- covers personal data that is collected by companies
- organisations must declare to the information commissioner what data they are collecting, why they are collecting it and abide by the DPA ‘principles’
who are Data subjects?
people whose data is being collected that have rights
who are data controllers?
people who process personal data within a company that must follow good information handling practices
what principles do the Data Protection Act include?
- data must be lawfully processed
- data must be processed for registered purposes
- data must be adequate, relevant and not excessive
- data must be accurate and up to date
- data must not be kept longer than is necessary
- data must be processed in line with the data’s subject’s rights
- data must be kept secure
- data must not be transferred to countries without adequate protection
what exemptions does the Data Protection Act include?
- national security
- crime detection and prevention
- tax collection
- household affairs
what does the Copyright, Designs and Patents Act of 1988 cover? what things does it say is illegal to do?
-Covers the rights of authors, musicians
It is illegal to
- Copy Software (pirate)
- sell or distribute copies of software
- Adapt software
- Transmit software
what must you have to be exempted from the Copyright, Designs and Patents Act and what is the penalty of committing a crime under the act?
-You have to have a licence
Penalty: unlimited fine and two years imprisonment
what is meant by a computer crime? give examples
this is an illegal act6 that has been committed using a computer
e. g
- theft of money/information/ goods using a computer
- using false identification to obtain a loan
what is meant by the term Malpractice? give examples
this is negligent or improper professional behaviour, breaking the company rules.
e. g
- excessive personal use of a computer
- wasting time on the internet
- accessing inappropriate sites
what is a virus?
- program written with the sole purpose of infecting computer systems
- they cause damage to a computer’s hard disk and is spread through email or removable storage devices. It is hidden and automatic
what is a worm?
a type of program that copies itself e.g use up all the memory and close the pc
what is a Trojan horse?
-looks like a innocent program (maybe to remove a virus) but when downloaded introduces another virus.
what is a database?
a collection of data items with links between them
what is a flat file database?
one table of data
what is a relational database?
many tables of data which are linked together via primary and foreign keys
what is the problem with flat files?
- data is duplicated
- data is inconsistent
what are the advantages of relational databases?
- data independence
- data consistency
- no data redundancy (no duplicated data)
- greater data integrity (greater data correctness)
what are the disadvantages of relational databases?
- more complex and costly to build
- users will need training to use it
- greater security issues can arise (because there are lots of different users)
describe what a database is made up of?
- a database is made up of records
- each record has fields
- each field has a data type
- fields can be coded to reduce space and speed up data entry
- a database allows validation checks
- each record has a key field (unique identifier)
what are the different types of access rights-hierarchy of passwords in database security?
- Full access
- read/write
- read only
- no access
what is meant by the term access rights?
-restrictions to a user’s access to only those files needed in order to perform their job
state the definition for password
-a series of characters which need to be typed in before access to certain ICT resources is allowed
what is a query? (include benefit for a hospital)
- when you interrogate (search) a database to find some information
- a query could be used to look for patients who have appointments the following week so a letter of reminder can be sent to them
what is report? (include benefit for a hospital)
- the output from a database in which the results are presented in a way that is controlled by the user
- a consultant can show treatment has bee effective by displaying the results in graphical form
what is meant by import/export? (include benefit for a hospital)
- transferring data from one piece of software to another
- merging names and addresses into a word processing program to produce appointment letters
what is speech synthesis?
-computers that produce human like speech
