4Feb/100
Computer Science: Study Notes [Outsourcing] – yr 12
| Advantages | |
| Give business freedom to focus on core compentencies | Cost an efficiency savings |
| Access to cheaper labour | Allows the company to focus on core operations' |
| Access world class help desk support | The company doesn't have space to accomidate a new employee and building onto an existing building is costly or cannot be done because of lack of space. |
| Access state of the art technology | Staff flexibility, allows the company to access additional resources |
| Disadvantages | |
| Wages of Australian workers may be pushed down. | Loss of control over the outsourced task |
| Quality of services recieved from outside sources may not be of the same standard | Hidden cost - one may sign a contract that contains hidden costs |
| Local workers have to compete on the global market | Threat to security and confidentiality - outsourcing propietry or knowledge, drawings, formulas. - may be at risk as these would have to be sent to the outsoucing company |
| Security issues in relation to sensitive data | |
| language and cultural barriers | |
| Alternatives to outsourcing | |
| Provide pathways for students to develop in these ICT areas | |
| Provide incentives to business to take on trainees | |
| Provice accredited training organisations to deliver ICT cources to a set standard | |
| Scholarships | |
| Tax benefits to Australian businesses to emply australian ICT workers over outsourced workers |
4Feb/100
Computer Science: Study Notes [Protocals & Misc] – yr 12
| Protocals | |
| TCP/IP | Transmission Control Protocol Internet Protocol |
| HTTP | HyperText Transfer Protocol, a protocol use to retrieving inter-linked resources called hypertext documents |
| SMTP | Simple Mail Transfer Protocol, internet standard for electronic mail. |
| WAP | Wireless Application Protocol, main use is to enable access to the mobile web from a mobile phone |
| Network Devices | |
| NIC | Network Interface Card |
| Switch | A computer networking device that connects network segments |
| Router | Connect two or more subnets Route and forwards information to the correct host, taking the quickest path. |
| Modem | Converts digital signals to analog signals, so that information can be transported on the telepone network |
| Transmission Media | |
| Coaxial | An electrical cable with an inner conductor surrounded by a tubular insulating layer typically of flexible meterial with high dielectric onstant all of which are surrounded by a conductive layerand finly cover with a thing insulating layer on the outside. Normally used for television transmissioms(cableTV) - but is also use as a high speed internet solution. |
| Twisted Pair | Is a form of cabling where two conductors are twisted togther to cancel out electromagnet interference (EMI) |
| Optical | A form of high speed communication, where light is passed throught optical fiber. |
| Wireless | Is the transfer of information over a distance without the use of electrical contuctors or wites. Uses radio ways to do so. |
| Network topogies | |
| Star | |
| bus | |
| mesh | |
| Token Ring | |
| Token bus | |
| Tree and hypertree networks | |
| Encryption Methods | Is the process of transforming plaintext using an algorith to make it unreadable. |
| SSL | Secure Socket Layer |
| MD5 | |
| Factors Effecting the functioning of ICT equipment | |
| EMI | ElectroMagnetic Interference |
4Feb/100
Computer Science: Study Notes [Types of Computers] – yr 12
| Handhelp Computers | Single User computers that provice ease of portability because of their small size. Such as PDA's, mobiles phones so forth |
| Portable Computers | Can be caried around easily eg laptops, notebooks, sub-notebooks or tablet computers |
| Thin client computers | Low-cost centrally managed computer with no extra drives, such as CD/DVD or expansions slots. They have limited capabilities and perform only essential applications. Thin clients download software from a network when needed making support, distribution and updating of software easier and less expensive - one example of this is cloud computing. |
| Desktop Computers | Relatively small, inexpensive single-user computer systmes that are highly versatile. Desktop computers can provide sufficient memory and stoage for most business computing desks. |
| Workstations | Workstations are more powerfull than PC's but still small enough to fit on a desk. They are used to support engineering and technical users who perform heavy mathematical computing, computer aided design (CAD). Users need powerful CPUs large amounts of main memory and high resolution graphics displays. |
| Servers | Servers are computers used by many users to perform a specific task, such as running nework or internet applications. Servers usually have large memory and stoage capacities along with fast and efficient communications abilities. Servers offer scalability easy to increase the processing capability so it can handle more users data in a given period. Scaling up adds more powerful processors Scaling out adds many more equal or even less powerful processors to increase the total data procession capacity. |
| Web Server | Handles traffic and communications -- needs to be refined.. |
| Internet Caching Server | Stores websites that are used frequently by an organisation |
| Enterprise server | Stores and provides access to programs that meet the needs of an entire organisation. |
| File server | Stores and coordinates program and datafiles |
| Transaction Server | processes business transactions |
| Blade server | houses many computer motherboards that include one or more processors, computer memory and computer storage and computer network connections. They all share a common power supply and air cooling source with a a single chassis. This makes the blade server more powerful and less expensive than a traditional system. |
| Server Farm | When an organisation houses a lage number of servers in the same room where the access to the machines can be controleld easil managed and maintained the facility is called a server farm. |
| Mainfraae Computers | A large powerful computer shared by doezens or hundres of concurrent users connected to the machine over a network. The mainframe computer much reside in a data center with special heating, ventilation and air conditioning equipment to control the remperature, humidity and dust levers. Most mainframes are kept in a secure data center with limited access to room. Mainframes can handle the millions of daily transactions associated with airline hotel/motel reservation systems. |
| Supercomputers | The most powerful computers with the fastest processing speed and highest preformance. |
| Microcomputer | Small personal computers PC's that are based on an intergrated circuit or chip called a microprocessor and are designed for use in homes and small organisations. |
4Feb/100
Computer Science: Study Notes [Programming Def's] – yr 12
| Reference | http://4dahl.com/howto/programdevelopmentsteps.html |
| Word | Definition |
| Algorithm | A set of simple instructions that combine to accomplish a task. |
| Data Validation | |
| Global data | Data that can be addressed by any process while in kernel mode for example tables such as open file table and process tavle and other data maintained by the kernel such as buffer |
| Local data | |
| Algorithm | A detailed outline A recipe |
| Pseudo code | Pseudo English is an intended outline with key words showing structure. |
| Modular design | Modular design involves grouping tasks together because they perform the same function. |
| Top-down development | IN the top-down development of a program design, a general solution to the problem is outlined first. This outline is then divided gradually in to more detailed steps until finally the most detailed levels have been completed. It |
| Types of programming | |
| Procedure Driven Programming | The procedure-driven design bases on the idea that the most important feature of a program is 'what' it does. |
| Event Driven Programming | The event driven program design is based on the idea that an event or interaction with the outside world can cause a program to change from one know state to another. |
| Data driven Programming | The data driven program design is based on the idea that the data in a program is more stable that the processes involved. |
| Object oriented programming | object oriented programming breaks the problem into a set of separted objects that perform actions and relate to each other. |
4Feb/100
Computer Science: Study Notes [OSI Model + Summerised ] – yr 12
| The OSI Model | ||||
| Definiton | Protocols | |||
| 7. Application layer | This layer interacts with the software -> closest to the end user | ftp, http | ||
| 6. Presentation | responisble for delivery and formatting of information | ASCII, LPP | ||
| Host Layers |
5. Session | Controls the connections between computers. Establishes, manages and terminates the connection between local and remote applications |
ADSP, ZIP, PAD | |
| 4. Transport | Provides transfer between users, reliable services to the upper layers controls the flow, segmentation/ desegmentation and error control. |
TCP, UDP, SPX | ||
| 3. Network | Provides the functional means of transferring data from source to the destination as well as amintain qaulity of service requested by the transport layer. |
IPv4, IPv6 | ||
| Media Layers |
2. Data-link | Provides the function and procedural means to transfer between network devices as well as finding possilbe errors in the physical layer. |
Ethernet, ATM | |
| 1. Physical | The physical devices that make up the network - such as hubs, switchs and calbes |
|||
| OSI MODEL | All People Seem To Need Data Processing | |||
| Summerised OSI Model | Protacals | |||
| 7. Aplication Layer | User Application Services | DNS, FTP, HTTP, SMTP | ||
| 6. Presentaion Layer | Data Translation; Compression and Encryption | SSL | ||
| Host Layers |
5. Session Layer | Session Establishment, Management and Termination | NetBIOS | |
| 4. Transport Layer | Flow control, Connections | TCP, UDP | ||
| 3. Network Layer | Logical addressign; Routing; error handling and diagnostic | IP, NAT, IPv6 | ||
| Media Layers |
2. Data-Link | Error detection and handling of the physical layer; Addressign; Data Framing Logical Link Control | ATM, PPP | |
| 1. Physical | The network topology and design, hardware specifications. | Ethernet |