A2 IT

Human Computer Interface

What makes a good HCI....

• Layout Appropriate To Task
• Consistency of signposting and pop up information
• Clear navigational structure
• Built in / online helpfiles
• Shortcuts for experts - Wizard for Novice

HCI For Disabled

• Speech to text- amputees
• Text to speech - blind/visually impaired
• Colour Blindness- no red or green
• Customisable to needs of the user
• Screen magnifier
• Braille keyboards

Networks

Ring Networks
Advantages
Quick - one direction
Least cable - cost down
Simple to set up
Disadvantages
Break --> all down
Difficult to locate

Bus Networks
Advantages
1 PC Unplugged does not mean network down
Easier to add computers/printers than ring
Disadvantages
Possible Collisions- slower than ring
More expensive than ring network
Harder to set up than ring network

Choice of Network Factors

Size of Organisation
LAN ( Data Comms.) / WAN (Tele Comms.)

How the system will be used
No. of applications
File Sizes

Existing Systems to Integrate
Not from scratch, need to fit in
Expand e.g.) when new branch opens
Support peripherals

Performance
In terms of : reliability/user friendliness/capacity/speed of processing
Different parts of organisation- different performace required
E-commerce systems may require greater speeds/capacity/reliability

Security

Cost

Misuse

• Introduction of viruses
• Personal Use
• Cyber Bullying
• Misuse of data for own business - sell to others
• Licensing

Code of Conduct

Definition - Rules created by management for employee use

• Responsibilities
• Rights of others
• Legislation
• Malicious Damage
• Access Rights
• Security
• Consequences of breaking the code
• Complying with licensing agreement

E-Commerce

Requires.....
1) Trained/Skilled Staff
2) Catalogue of Stock
3)Payment System
4)Database of Orders
5)Order Tracking

Advantages to Business
Lower Start-up costs
Wider customer base
Can sell 24/7
Disadvantages to Business
System down = no sales
Increased Competition

Advantages to Customer
No travelling
Disabled Use
Price Comparison
Greater choice + Obscure Goods
Disadvantages to Customer
Fraudulent Sites
Security
Returning Goods
Hard to assess the quality
Social Pleasure of Shopping lost

Lack of Control of the Net

Censorship

Can't trust information

****/Violence

Plaigarism

Thailand - No Copyright Law

Grooming/Paedophiles

Risk Analysis

1) Identify Risk e.g.)Virus

2) Probability of Happening

3) Consequences of Happening

4) Current Equipment Level

5) Prepared to spend money to minimise the risk

File Transfer Protocol

Definition
A standard set of rules that have been established to allow the exchange of (large) files over the internet.

Advantage
No file size limit - Used for uploading websites to the internet.

Maintenance

Perfective

Adapting the system
Efficiency

Adaptive

Changes in law - VAT, Tax Rate changes

Corrective

Bugs
Security

Management Information Systems

Effective MIS
Accurate and Relevant Data
Info when required
Range otf Users
Output in appropriate form
Flexibility of system

Good MIS
Improve communication amongst management and employees
Allows individual project planning
Avoid information overload

Poor MIS
Complexity of the System
Inadequate initial analysis
Lack of management knowledge
Poor communication between professionals
Inappropriate hardware/software

Management Information Systems

Definition
Systems that convert data from internal or external sources into information and resources designed to support the choices of managers.

Example
Looking at pupil attendance figures to try and see if there are trends and to ensure less pupils truant

Databases

Relational Database
A group of tables linked by primary and foreign keys

Data Normalisation
A staged process to simplify data structure so that attributes are not dependent on the entity

Distributed Database
A single database that is under the control of a database management system, where the strange devices are not all attached to a common processor

Distributed Databases

Advantages
Stored at two locations
Faster to query hard disk than telecom
Less network traffic
No dependence on central site
If data lost on central state, it can be reducplicated

Disadvantages
Reliant on internet
Data inconsistency
Security threats
Heavy reliance on communications

Internet Connection Types

• Broadband not avaliable everywhere
• Broadband does not tie up phone line
• Broadband allows more devices/computers to be connected to the internet at the same time

Mobile Access to the Internet

Advantages
Can work more productively
Collaboration
Can easily modify plans - flights, trains and hotels

Disadvantages
Can be very expensive
Black spots/poor connectivity
Battery life
Work progress hampered by distractions

Security Policies

 1) Audit Trails

2) Physical Security - Locks & Biometric Devices

3) User ID's - levels of access

4) Firewall

5) Code of Conduct

6) Training

7) Backup/disaster recovery

8) Disciplinary Procedures

Audit Log - WHO? WHAT? WHERE? WHEN?

Distributed Computing

Definiton: A series of computers networked together working on the same problem with the same shared data processing.

S.E.T.I
(Search for extraterrestrial intelligence)

Advantages
Cheaper than supercomputer
Anyone can contribute

Disadvantages
Security
Reliant on networking
Good will
Communication break down

Management of Change

1) New Skills
2) Organisation Structure
3) Work patterns being altered
4) Change of internal procedures
5) Workforce Fears

Internal Procedures
Tradutional jobs done quickly, so they  may have to undertake new duties. Can cause stress if not involved in decisions or given proper training.

Workforce Fears
Redundancy
Loss of status
Fear of looking ridiculous
Changes in location

How to manage change
Training
Explanation of advantages
Learn new skills
Involve them
Keep social groups together

Databases

Advantages of relational database
No redundant data
Data consistency
Data integrity
Data independence - CSV
Access Rights

Definitons
Redundancy - Storing an item of data more than once
Consistency - The relationship between the input data, processed data and output data
Integrity - Correctness of the data
Independence - The data and applications/programs used to access it are indpendent/seperate

Data

Data Warehouse
Somewhere where a lot of data is held (archived)
Large archive used for decision making

Data Mining
Interrogating the data to find the patterns in the data  which is stored in the warehouse.

Example
Going through data to find patterns
Positioning of products within a store

Remote Management

1) Guide users through problems
2) Check to see no unauthorised software loaded on machines
3) Log off users
4) Check on components to see if any failing
5) Shut down status
6) Rebuild stations/ re setup stations/install/update software
7) Send instant messages
8) Control stations
9) Clear printer queues

Changeover Strategies

1) Direct - High risk but few resources (training)

2) Parallel - Reduces risk, allows comparison, duplication of work

3) Phased - problems, split into quarter

4) Pilot - More manageable - takes a lot longer

Disaster Recovery

1) Cost - Backup systems

2) Risk - Problems, Likelihood etc.

3) Data - Frequency of backup ?

4) Hardware/ Software comms. - Paint the picture

5) Personnel, Responsibilities and training - Make someone responsible for backups

6) Procedures - Describe backing up and test backups

Moral,Social and Ethical Issues

Moral Issues
Deliberately setting up websites with false information
Bullying
Inappropriate websites - ****,violence and plaigarism
Email to give bad news - redundancy, fired
Spread rumours

Social Issues
Plaigarism
Sending spam
Monitoring staff use
Wi-fi- no permission
Photo editing to distort reality

Social Issues
Privacy
Gambling addiction
Obesity
Addiction to computer games

Network Performance

Speed

Reliability

Cheap - cost

User Freindly

Teleworking for Employee

Advantages
Cost and time of commuting
Live anywhere
Disabled
Work own hours
Stress reduction

Disadvantages
Utility Bills
Social isolation
Lower pay
Boundary between home and work lost
No posh offices

Teleworking for Employer

Advantages
Smaller offices - less rent
Fewer cleaners = less wages
Sick staff
Staff on flexitime
Employ anyone - vast pool of talent

Disadvantages
Monitoring staff
Harder to manage
Difficult to hold meetings
Pay for hardware
Data security
How hard are people working

Teleworking Effects on Society

Reduction in greenhouse gases and congestion = less pollution

Rural communities/oppurtunities/Shares the wealth

Family relations and more time at home

Feasability Report

Definition - The summary of an inital investigation to look at the lielihood of being able to create a new system

Includes...
User Requirements
Outline correct system
Identification of problems
Existing hardware and software
Benefits of new system
Is the new system worth it
Cost/benefit analysis
Conclusions - Yes/No

Investigation Methods
Interview
Observation
Questionnaire
Inspection of records - paper based system

Wireless Networks

Advantages of Wi-Fi
Work wherever you want within zone
Cheap -> no cable
Networks in old listed buildings
Global set of standards - all over the planet

Disadvantages of Wi Fi
Limited range
Transmission speed - currently slower than cable
Interference- from other wireless acces points
Power consumption
Health
Security

Online Databases

Company --> Orders, stock and customers

Customers -->  Stock and previous orders

P2P vs Client Server

Cost - Server is more expensive
Status- P2P all the same. Client server, server more important
Knowledge- P2P easier
Reliance on server
Security - network manager responsible
Backup - network manager accountable and easier as 1 machine
P2P small networks only (15 or less)

Dissatisfaction with ICT systems over time

Speed - no space on hard drive

Compatibilty

Security

Browser issues - lack of support

Change of business needs

Cost of user support

Web Crawler

Definition
A program that automatically browses web pages

e.g) Harvesting email addresses

Boolean Searching

AND

OR

NOT