1. What are some problems associated with assessing the costs of IT?
Placing a dolar value on the cost of IT investments may not be as simple as it sounds.
One of the major challanges that companies face is to allocate fixed costs among different IT projects. Fixed costs are those coss tah tremain teh same regardless of any change in teh activity level.
For IT, fixed costs include infrastructure cost, cost of IT services, and IT management cost. For e.g. teh salary of the IT director is fixed, and afdding one ore application will not change it.
Another complication is taht the cost of a system does not end when the system is installed. Costs for maintaining, debugging, and improving the system can accumulate over many years. In some caes, the company does not even anticipate them when it makes the investment. E.g. is the cost of the year 2000 (Y2K) reprogramming projects that cost organisations worldwide billions of dollars at the end of the 2oth century.
2. What difficulties accompany the intangible benefits from IT?
-benefits may be harder to quantidy, especially becasue many of them are intangible (e.g. improved customr or partner relations or iproved decision making.
-The fac tthat org's use IT for several purposes further complicates benefit analysis.
- In addition, to obtain a return from an IT investment, the company must implement the technology successfully.
- In reality, many systems are not implemented on time, wihtin budget, or with all the features originally envisioned for them.
- Finally, the proposed system may be "cutting edge." In these cases there may be no previous evidence of what sort of financial payback the company can expect.
3. Define NPV and ROI, and business case approaches.
Net Present Value: calculations for cost-benefit analyses. Using the NPV method, analysts convert future values of benefits to their present-value equivalent by "discounting" them at the organisation's cost of funds. They can then compare the present value of the future benefits to the cost required to achieve those benefits and determine whether the benefits exceed the costs.
ROI: measures managements effectiveness in generating profits with its available assets. It is a percenatge, and the higher the percentage return the better.
4. What type of companies provide outsourcing service?
Small/medium sized companies with few IT staff and limited budgets are best served by outside contractors. Acquiring IT applications from outside contractors or external organisations is called outsourcing.
Several types of vendors offer services for creating and operating IT systems inclusing e-commerce applications. Amnay softeare companies, from IBm to Oracle, offer a range of outsourcing services for developing, operating, and maintaining IT applications. IT outsourcers such as EDS, offer a variety of services.
5. Define ASPs and list their advantages to companies using them
Application Service Provider (ASP) is an agent or a vendor whoasssmebles teh software needed by enterprises and packages the software with services such as developemnt, operations, and maintenance. The custoerm then accesses these applciations via the internet.
-using hosting vendors is particualrly desirable option for SME businesses.
-developing and opearting IT applications in-house can be time-consuming and expensive for these entities.
6. List some disadvantages of ASPs.
Leasing from ASP's offers such compaies several advantages.
- It saves various expenses (labour costs) in the initial developement stage.
- Helps reduce the costs of software maintenance and upgrading and user training over the long run.
- the companycan select another software product from the vendor to meet its chamging needs.
- This oppostion savse the comapny the costs of upgrading the existign software.
- Makes teh company more competitive by enhancing teh comapy's ability to adapt to the changing market conditions.
7. List the major steps of selection of a vendor and a software package.
Step 1. Identify Potential Vendors through software catalogues, technical and trade journals, consultants and industry analysts, web searches.
Step 2. Determine the evaluation criteria.
-characteristsics of the vendor
-functional requirements of the sysetm
- technical requirements tah tthe software must satisfy
- amount and quality of documentation provided
- vendor support of the package
Step 3. Evaluate Vendors and Packages
Often the gives the vendors and packages an overall score:
- assigning an importnace weight to each of the criteria
- ranking the vendors on each of the weighted criteria (1 to 10)
- and then multiplying the ranks by the associated weights
Step 4. Choose the vendor and package
Once teh company has shortened the list of potential suppliers, it can begin negotiations with these vendors to determine how their packages might be modified to remove any discrepancies with teh companys IT needs.
Step 5. Negotiate a contract.
It specifies both the price of the software and the type and amount to support that the vendor agrees to provide. The contarct will be the only recourse if ither the system or the vendor does not performa s expected.
step 6. Establish a Service Level Agreement
SLA's are foraml agreemnts that specify how woerk is to be divided between the company and its vendors.They describe how quality checks will be made and what is to be done inc ase of dsiputes.
8. Describe a request for proposal (RFP).
is a document that is sent to potential vendors inviting them to submit a prposal taht describes their software package and expalins how it would meet the companys needs. The RFP provides the vendors with information abou tt eh objectives and requiremnts of the system. Specifically, it describes the enviroenmtn in which the system will be used, the geanearl criteria tah tthe comapny will use to evaluate the proposals and the conditions for submitting the proposals.
9. Describe SLAs.
SLA's are foraml agreemnts that specify how woerk is to be divided between the company and its vendors.They describe how quality checks will be made and what is to be done in case of dsiputes.
Accompish tehse goals:
1. definign the responsibilities of both partners
2. providing a framework for designing support services
3. allowing the company to retain as much control as possible over its own systems.
Sunday, October 19, 2008
Sunday, October 12, 2008
Ch 9: Managerial Support Systems
1. Describe the decision-making process proposed by Simon.
Simon (1977) described the process as composed of three major phrases: intelligence, design and choice. A fourth phrase, implementation was added later.
- The decision making process starts with the intelligence phrase, in which mnagers examine a situation and identify and define the problem.
- In the design phase, decision makers construct a model that simplifies the problem. They do this by making assumptions that simpify reality and by expressing te relationships among all the relevant variables. Managers than validate the model by using test data. Finally, decision makers set criteria for evaluating all potential solutions that are proposed.
- The choice phrase involves selecting a solution, which is tested "on paper".
- Once this proposed solution seems to be feasible, decision making enters the last phase - implementation. Implementation is successful if the proposed solution actually resolvesd the problem. Failure leasds to a return to the rpevious phases. Computer based decison support attempts to automate several tsks in the decision making process, in which modeling is the core.
2. Why do managers need IT support?
- the number of alternatives to br considered is constantly incresing due to innovations in technology, improved communications, the developemnt of global markets, an the use of the internet and e-business. The more alternatives that exist, the more copmputer-assisted search and comoarisons are needed.
- the decisions must be made under time pressure. Frequently, it is not possible to process informationmanually fast enough to be effective.
- Due to increased uncertainty in teh decison environment, decisions are becoming more complex. It is useually necessary to conduct a sophisticated analysisi in order to make a good decision. such analysisi requies the use of modeling.
- It is often necessary to access remote informaion rapidly, consult with experts, or conbduct a group decision-making session, all without incurring large expenses. Decision makers can be in different locations, as can the information. Bringing nthem all togethr quickly and inexpensively may be a difficult task.
3. Describe the decision matrix.
The three primary classes of problem structure and the three broad categories of the nature of decisions can be combined in a decsion support matrix taht consists of nine cells. Lower-level managers usually peform the structured and operational control-oriented tasks (cells 1, 2 and 4). The tasks in cells m3, 5, and 7 are usually the responsibility of middle managers and professionalstaff. Finally, tasks in cells 6, 8 and 9 are generally the responsibility of senior executives.
4. Describe the capabilities of data mining.
-Reatiling and Sales. Predicting sales, preventing theft and fraud, and determining correct inventory levels and districution sceduales among outlets.
- Banking. Forecasting levels of bad loans and fraudulent credit card use, predicting credit card spending by new customers, and determining whichc kinds of customers will best respond to (and qualify for) new loan offers.
- Manufacturing and Production. Predicting machinery failures and finding key factors that help optimize manufacuring capacity.
-insurance. Forescaring claim amounts and medical coverage costs, classifying the most important elemnets that affect medical coverage, and predicting which custoemrs will buy new insurance policies.
- Policework. Tracking crime patterns, locations, and criminal behaviour; identifying attributes to assist in solving criminal cases.
- Healthcare. Correlating the demographics of patients with critical illness and developing better insights on how to identify and treat symptoms and their causes.
- Marketing. Classifying customer demographics taht can be used to predict which customers will respond to a mailing or buy a particular product.
5. What are some of the capabilities of digital dashboards?
- Drill-down. Ability to go to details, at several levels; can be done by a series of menus or by direct quries (using intelligent agents and natural language processing).
- Critical Success Factors (CSF). The factors most critical for the success of business. These can be organisational, industry departmental, etc.
- Key Performance Indicators (KPI's). The specific measures of CSFs.
- Status Access. The latest data available on KPI or some other metric, ideally in real time.
- Trend Analysis. Short, medium and long term trend of KPIs or metrics, which are projected using forcasting methods.
- Ad-hoc analysis. Analyses made any time, upon demnads and with any desired factors and relationships.
-Exception reporting. Reports that highlight deviations larger than certain thresholds. Reports may include only deviations.
Simon (1977) described the process as composed of three major phrases: intelligence, design and choice. A fourth phrase, implementation was added later.
- The decision making process starts with the intelligence phrase, in which mnagers examine a situation and identify and define the problem.
- In the design phase, decision makers construct a model that simplifies the problem. They do this by making assumptions that simpify reality and by expressing te relationships among all the relevant variables. Managers than validate the model by using test data. Finally, decision makers set criteria for evaluating all potential solutions that are proposed.
- The choice phrase involves selecting a solution, which is tested "on paper".
- Once this proposed solution seems to be feasible, decision making enters the last phase - implementation. Implementation is successful if the proposed solution actually resolvesd the problem. Failure leasds to a return to the rpevious phases. Computer based decison support attempts to automate several tsks in the decision making process, in which modeling is the core.
2. Why do managers need IT support?
- the number of alternatives to br considered is constantly incresing due to innovations in technology, improved communications, the developemnt of global markets, an the use of the internet and e-business. The more alternatives that exist, the more copmputer-assisted search and comoarisons are needed.
- the decisions must be made under time pressure. Frequently, it is not possible to process informationmanually fast enough to be effective.
- Due to increased uncertainty in teh decison environment, decisions are becoming more complex. It is useually necessary to conduct a sophisticated analysisi in order to make a good decision. such analysisi requies the use of modeling.
- It is often necessary to access remote informaion rapidly, consult with experts, or conbduct a group decision-making session, all without incurring large expenses. Decision makers can be in different locations, as can the information. Bringing nthem all togethr quickly and inexpensively may be a difficult task.
3. Describe the decision matrix.
The three primary classes of problem structure and the three broad categories of the nature of decisions can be combined in a decsion support matrix taht consists of nine cells. Lower-level managers usually peform the structured and operational control-oriented tasks (cells 1, 2 and 4). The tasks in cells m3, 5, and 7 are usually the responsibility of middle managers and professionalstaff. Finally, tasks in cells 6, 8 and 9 are generally the responsibility of senior executives.
4. Describe the capabilities of data mining.
-Reatiling and Sales. Predicting sales, preventing theft and fraud, and determining correct inventory levels and districution sceduales among outlets.
- Banking. Forecasting levels of bad loans and fraudulent credit card use, predicting credit card spending by new customers, and determining whichc kinds of customers will best respond to (and qualify for) new loan offers.
- Manufacturing and Production. Predicting machinery failures and finding key factors that help optimize manufacuring capacity.
-insurance. Forescaring claim amounts and medical coverage costs, classifying the most important elemnets that affect medical coverage, and predicting which custoemrs will buy new insurance policies.
- Policework. Tracking crime patterns, locations, and criminal behaviour; identifying attributes to assist in solving criminal cases.
- Healthcare. Correlating the demographics of patients with critical illness and developing better insights on how to identify and treat symptoms and their causes.
- Marketing. Classifying customer demographics taht can be used to predict which customers will respond to a mailing or buy a particular product.
5. What are some of the capabilities of digital dashboards?
- Drill-down. Ability to go to details, at several levels; can be done by a series of menus or by direct quries (using intelligent agents and natural language processing).
- Critical Success Factors (CSF). The factors most critical for the success of business. These can be organisational, industry departmental, etc.
- Key Performance Indicators (KPI's). The specific measures of CSFs.
- Status Access. The latest data available on KPI or some other metric, ideally in real time.
- Trend Analysis. Short, medium and long term trend of KPIs or metrics, which are projected using forcasting methods.
- Ad-hoc analysis. Analyses made any time, upon demnads and with any desired factors and relationships.
-Exception reporting. Reports that highlight deviations larger than certain thresholds. Reports may include only deviations.
Monday, October 6, 2008
Chapter 8: Organisational Information Systems
Section 8.1
TPSs monitor, collect, store, and process data generated from all bsuiness transactions. These data are inputs to the organisation's database. Theye are also inputs to teh functional information systems, decison support systems, customer relationship management, knowledge management, and e-commerce. TPSs have to handle high volume and large variations in volume. (e.g. during peak times) efficently, avoid errors and downtime, record results accureltly and securely, and maintain privacy ajnd security.
First data is collected by people or sensors and are enterd into the computer via any input device. Next, teh system processes data in one of 2 basic ways: batch processing (palcing data into groups). The system then prepares and processes the batches periodically (e.g every night).
Section 8.2 - Before You Go On…
1. What is a functional area information system? List its major characteristics.
FAISs provide information mainly to lower and middle level managers in teh functional areas. They use this information to help them plan, organisae and control opeartions. The information is provided in a variety of reports. E.g comparitive reports compare, for e.g., the peformances of different business units or time periods.
2. How does an FAIS support management by exception? How does it support on-demand reports?
Section 8.3
1. Define ERP and describe its functionalities.
Enterprise Resource Planning Systems integrate the planning, managemnt, and use of all of an organisations resources. The major objectives of ERP stsrems are to tightly integrate the functional areas of the organisation and to enable information to flow seamlessly across the functional areas. Tight integration means that chjamnges in one functional area are immediately reflkected in all other pertinent funcational areas.
ERP provide the information necessary to vcontrol the business processes of the orgnaistaion. A business process is a set of relkated steps or preocedures designed to produce a specific outcome. Business processes can be located entirely within one functional area, such as approving a credit card application or hiring a enw employee.
ERP software included a set of interdependednt software modules, linekd o a common database, taht provide support for the internal business processes in the following functional areas: finance & marketing, sales & marketing, manufacturing & production.
2. List some drawbacks of ERP software.
- expensive
- extremely complex
- time consuming to implement.
- Companies may need to changeeisting busines processes to fit the predefined business processes of the software.
Section 8.5
1. Define a supply chain and supply chain management (SCM).
Supply Chain: refers to the flow of materials, information, money, and services from raw material suppliers, through factories and warehouses to the end custoemr. A supply chain also includes the organisations and processes taht create and deliver products, infomation, and services to end customers.
SCMs: function is to plan, organise, optimise the supply chains activities. Like other functional areas, SCM utilises information systems. The gola of SCM systems is to reduce friction along the supply chain. mFriction can invlve increased time, costs, and inventories as well as decreased customer satisfaction. SCM systems, then, reduce uncertainty and risks by decresing inventorylevels and cycle time and improving business processes ans customer service. All these benefits contribute to increased profitability and competitiveness.
2. List the major components of supply chains.
Involves 3 segments:
1. Upstream: where sourcing or procurement from external supplers occurs (orders, info, payments, returns)
2. Internal: where packaging, assembly, or manufacturing takes place.
3. Downstream: where distribution takes place, frequently by external distributors (products, services, info).
INTERNAL
Tier 3 Tier 2 Tier 1 <----------> Distributor or
Suppliers <->Suppliers<-> Suppliers<->manufacturer<-> Wholesaler<->Reatiler<->Customer
There are 3 flows in teh supply chain:
- Material Flows: are the physical products, raw materials, supplies, asn so forth that flow along the chain. Also incude reverse flows (returned products)
- Information Flows: consist of data taht are related to demand, shipments, orders, returns,l and scheduales, as well as chanegs in any of tehse data.
- Financial Flows: involve money transfers, payments, credit card information and authorisation, payment schedules, e-payments, credit-related data.
3. What is the bullwhip effect?
refers to erratic shifts in orders up and down the supply chain. Basically, customer demand variables can become magnified when they are viewd through the eyes of managers at each link in teh supply chain. If each distinct entiry that makes ordering and the inventory decisions palces its own interests above those oif the chain, then stockpiling can occur at as many as seven or eight locations along the suppy chain.
4. What are some solutions to supply chain problems?
Section 8.6
1. Define EDI and list its major benefits and limitations
Electronic Data Interchange is a communication standard that enables business partners to exchange routine documents, such as purchasing orders, electronically. EDI formats these documents according to agreed upon standards and then transmits message susing a converter, called a translator. The message travels over either a value added network (VAN) or the internet.
Benefits:
-minimizes data entry errors becsue each entry is checked b ythe computer.
-the length of the message can be shorter, and the emssgaes are secured.
-reduces cycle time
- increases productivity
-enhances customer service
minimises paer usgae and storage.
Limitations:
-implementing a EDI system involves a significant initial investment
-ongoing operation costs are high due to use of expensive, private VANs.
traditional EDI systems is inflexible. E,g it is difficult to make qucik changes, such as adding business partners.
- requires a long start up period
-business processes must sometimes be restructured to fit EDI requirements
2. Define an extranet and explain its infrastructure (in relation to Internet technologies).
The main goal of extranets is to foster collaboration betweena nd among bsuiness partners. An extranet is open to selected B2B suppliers, custoemr snad other busienss partners. These indiciduals access the internet through teh internet. Extranets enable people who are located outside a company to work together with the comapny's internally located emmployees. An extranet also enables external business partners to enter the corportate intranet, via the internet, to access data, palce orders, check status, communciate and collaborate. It also enables partners to perform self-service activities sucha s checking the status of orders or inventory levels.
Extranets uses virtual private betwork (VPN) technology to make communication over the internet more secure. The intenet-based extranet is far less costlythen propreitory networks.
The major benefits of extranets are:
- faster processes and informtion flow
-improved order entry and custoemr service
- lower costs (communciation, travel, administartive overhead)
-overall improvement in business effectiveness.
3. List and briefly define the major types of extranets.
-A Company and Its Dealers, Customer or Suppliers: such as extranet is centred arounbd one company. E.g FedEx extranet that allows custoemr sto track the status of a package.
-An Industry Extranet: The major palyers in an industry may team up to create an extranet taht will benefit all of them. E.g. ANXeBusiness nables comapnies to collaborte effectiveky through a network that provides a secure global medium for B2B informaytion exchange.
- Joint Ventures and Other Business Partnerships: partners in a joint venture use the extranet as a vehicle for communication and collaboraqtion. An example is Bank of America's extranet for commercial loans. The partners involved in making such loans include a lender, a loan broker, an escrow company and a title company. The extranet connects lenders, loan applicants, and the loan organisaer, bank of America.
Chapter 7: Wireless, Mobile Computing and Mobile Commerce
1. Identify common wireless devices and their application to business
- The Wireless Application Protocol (WAP) - is the standard that enables wireless devices with tiny display screens, low-bandwidth connections, and minimal memory to access Web-based information and services.
E.g. pagers, e0mail handhelds, personal digital assisstants (PDAs) and mobile phones. The capabilities of tehse devices include: bluetooth, Wi-Fi, a digital camera, address book, access to email, instant messaging, MP3 player, internet access -The Blackberry 8800.
2. Describe the various types and general characteristics of wireless transmission media/technologies - microwave, satellite, infrared and radio waves.
-Microwave transmission systems are widely used for high volume, long distance, line-of-sight communication (transmitter and reciever must be in view of each other). Therefore, microwve toweres cant be spaced more than 30 miles apart as world is curved not flat. Susceptible to environmental interference during sever weather such as heavy rain/snow storms. Being replaced by staellite communication systems.
- Satelllite Transmission systems: make use of communication satelittes. currently, there are three types of satellites around the earth: geostationary (GEO), medium earth orbit (MEO), and low earth orbit (LEO). Geo fartherst for the eart and LEO the closest. As with microwave transmission, satellites must recieve and transmit data via line of sight. It overcomes the limitations of microwave data relay stations becsue the hight the satellite orbits, the larger the footprint. In contrast to line of sight transmission with microwave, satellites use broascast transmission, whcih sends signals to many recievers at one time. So, even though satellites are line-of-sight like microwave, they are high enough for broadcast transmission, this overcoming the limitations of microwave.
- radio transmisson: uses radio-wave frequencies to send data directly between transmitters abd recievers. radio transmission has several advanatages: radio waves travel through normal office walls, inexpensive and easy to install, transmit data at high speeds. Therefore, being used to connect computers to LAN and peripheral equiptment.
- Infrared Transmission: Infrared light is a red light that is not commonly visible to human eyes. Common applications include: remote cotrols for tv, VCRs, DVDs and CD players. Used for short -distance connections between computers and peripheral equiptment and LAN.
3. What is bluetooth/how is it used?
Is a industry specification used to create small personal area networks (a computer netwrok used for communication amongcomputer devices clsoe to one person). A bluetooth is a chip technology that enables short-range connection (data and vocie) between wireless devices. E.g mobile phones.
4. What are WLAN's, Wi-Fi, WWAN's, WiMax?
- Wireless Local Areda Network (WLAN): A computer network in a limited geograpical area taht used wireless transmission for communication.
- Wireless Fidelity (Wi-Fi): is a medium range WLAN, which is basically a wired LAN but without cables
- Wireless Wide Area Networks (WWANs) :Wireless WANs, which can bridge branch offices of a company, cover a much more extensive area than wireless LANs. Unlike WLANs, which offer limited user mobility and instead are generally used to enable the mobility of the entire network, WWANs facilitate connectivity for mobile users such as the traveling businessman. In general, WWANs allow users to maintain access to work-related applications and information while away from their office.
- Wireless Broadband or WiMax: has a wireless access range of up to 31 miles, compared to 300 feet for Wi-Fi and 30 feet for bluetooth. It is a secure system, and it offers features such as voicve and video.
WiMAX, a contraction of Worldwide Interoperability for Microwave Access, is a telecommunications technology that provides for the wireless transmission of data in a variety of ways, ranging from point-to-point links to full mobile cellular-type access. The technology provides broadband speed without the need for cables.
5. What are the drivers of mobile computing and m0bile commerce
Mobile commputing: refers to a real-time, wireless connection between a mobile device and othercomputing environments, such as internet/intranet. 2 characteristics that differentiate it from other forms of computing: mobility and broad breach. Mobility is based on the fact that users carry a mobile device with them and can initiate a real-time contract with other systems from wherever tehyhappent o be. Broad rech refers to the fact taht when users carry an open mobile device they can be reached instantly.
Mobile Commerce: Electronic commerce transactions that are conducted in a wireless environment, especially via the internet.
The developemnt of m-commerce is driven by the following factors:
- Widespread availability of mobile devices.
- No need for a PC. Access internet via a smart phone or another wireless device.
- The "cellphone culture": widespread use of mobile phones.
- Declining prices: price of wiireless devices is declining and will continue to decline.
Bandwidth improvement: to conduct m-commerce you need sufficeint bandwidth for transmitting text, voice, video and multimedia. Wi-Fi, 3G cellular technology, and WiMax provide the neccessary bandwidth.
6. Be able to explain how mobile technologies can be applied to business solutions
7. Explain the nature of RFID
Radio Frequency Identification Technology: A wireless system that allows manufacturers to attach tags with antennas and computer chips on goods and then track their movement through radio signals. Was developed to replace barcodes. An RFID tag is an object that can be applied to or incorporated into a product, animal, or person for the purpose of identification and tracking using radio waves. Some tags can be read from several meters away and beyond the line of sight of the reader. Tags remain expensive so not used in low-priced items.
8. Identify the 4 main security threats that arise from the use of mobile technologies
The 4 major threats to wireless networks are rogue access points, war driving, eavesdropping, and radio frequency jamming.
-A rogue access point is an unauthorised access point to a wireless network.
-war driving is the act of locating WLANs while driving (or walking) around. To war drive all you need is a Wi-Fi detector and a wireless enabled computer.
-Eavesdropping refers to efforts by unauthorised users to access data taht are travelling over wireles networks.
-Radio Frequency jamming a person or a device intentionally or unintentioanlly interferes with your wiureless network transmissions.
- The Wireless Application Protocol (WAP) - is the standard that enables wireless devices with tiny display screens, low-bandwidth connections, and minimal memory to access Web-based information and services.
E.g. pagers, e0mail handhelds, personal digital assisstants (PDAs) and mobile phones. The capabilities of tehse devices include: bluetooth, Wi-Fi, a digital camera, address book, access to email, instant messaging, MP3 player, internet access -The Blackberry 8800.
2. Describe the various types and general characteristics of wireless transmission media/technologies - microwave, satellite, infrared and radio waves.
-Microwave transmission systems are widely used for high volume, long distance, line-of-sight communication (transmitter and reciever must be in view of each other). Therefore, microwve toweres cant be spaced more than 30 miles apart as world is curved not flat. Susceptible to environmental interference during sever weather such as heavy rain/snow storms. Being replaced by staellite communication systems.
- Satelllite Transmission systems: make use of communication satelittes. currently, there are three types of satellites around the earth: geostationary (GEO), medium earth orbit (MEO), and low earth orbit (LEO). Geo fartherst for the eart and LEO the closest. As with microwave transmission, satellites must recieve and transmit data via line of sight. It overcomes the limitations of microwave data relay stations becsue the hight the satellite orbits, the larger the footprint. In contrast to line of sight transmission with microwave, satellites use broascast transmission, whcih sends signals to many recievers at one time. So, even though satellites are line-of-sight like microwave, they are high enough for broadcast transmission, this overcoming the limitations of microwave.
- radio transmisson: uses radio-wave frequencies to send data directly between transmitters abd recievers. radio transmission has several advanatages: radio waves travel through normal office walls, inexpensive and easy to install, transmit data at high speeds. Therefore, being used to connect computers to LAN and peripheral equiptment.
- Infrared Transmission: Infrared light is a red light that is not commonly visible to human eyes. Common applications include: remote cotrols for tv, VCRs, DVDs and CD players. Used for short -distance connections between computers and peripheral equiptment and LAN.
3. What is bluetooth/how is it used?
Is a industry specification used to create small personal area networks (a computer netwrok used for communication amongcomputer devices clsoe to one person). A bluetooth is a chip technology that enables short-range connection (data and vocie) between wireless devices. E.g mobile phones.
4. What are WLAN's, Wi-Fi, WWAN's, WiMax?
- Wireless Local Areda Network (WLAN): A computer network in a limited geograpical area taht used wireless transmission for communication.
- Wireless Fidelity (Wi-Fi): is a medium range WLAN, which is basically a wired LAN but without cables
- Wireless Wide Area Networks (WWANs) :Wireless WANs, which can bridge branch offices of a company, cover a much more extensive area than wireless LANs. Unlike WLANs, which offer limited user mobility and instead are generally used to enable the mobility of the entire network, WWANs facilitate connectivity for mobile users such as the traveling businessman. In general, WWANs allow users to maintain access to work-related applications and information while away from their office.
- Wireless Broadband or WiMax: has a wireless access range of up to 31 miles, compared to 300 feet for Wi-Fi and 30 feet for bluetooth. It is a secure system, and it offers features such as voicve and video.
WiMAX, a contraction of Worldwide Interoperability for Microwave Access, is a telecommunications technology that provides for the wireless transmission of data in a variety of ways, ranging from point-to-point links to full mobile cellular-type access. The technology provides broadband speed without the need for cables.
5. What are the drivers of mobile computing and m0bile commerce
Mobile commputing: refers to a real-time, wireless connection between a mobile device and othercomputing environments, such as internet/intranet. 2 characteristics that differentiate it from other forms of computing: mobility and broad breach. Mobility is based on the fact that users carry a mobile device with them and can initiate a real-time contract with other systems from wherever tehyhappent o be. Broad rech refers to the fact taht when users carry an open mobile device they can be reached instantly.
Mobile Commerce: Electronic commerce transactions that are conducted in a wireless environment, especially via the internet.
The developemnt of m-commerce is driven by the following factors:
- Widespread availability of mobile devices.
- No need for a PC. Access internet via a smart phone or another wireless device.
- The "cellphone culture": widespread use of mobile phones.
- Declining prices: price of wiireless devices is declining and will continue to decline.
Bandwidth improvement: to conduct m-commerce you need sufficeint bandwidth for transmitting text, voice, video and multimedia. Wi-Fi, 3G cellular technology, and WiMax provide the neccessary bandwidth.
6. Be able to explain how mobile technologies can be applied to business solutions
7. Explain the nature of RFID
Radio Frequency Identification Technology: A wireless system that allows manufacturers to attach tags with antennas and computer chips on goods and then track their movement through radio signals. Was developed to replace barcodes. An RFID tag is an object that can be applied to or incorporated into a product, animal, or person for the purpose of identification and tracking using radio waves. Some tags can be read from several meters away and beyond the line of sight of the reader. Tags remain expensive so not used in low-priced items.
8. Identify the 4 main security threats that arise from the use of mobile technologies
The 4 major threats to wireless networks are rogue access points, war driving, eavesdropping, and radio frequency jamming.
-A rogue access point is an unauthorised access point to a wireless network.
-war driving is the act of locating WLANs while driving (or walking) around. To war drive all you need is a Wi-Fi detector and a wireless enabled computer.
-Eavesdropping refers to efforts by unauthorised users to access data taht are travelling over wireles networks.
-Radio Frequency jamming a person or a device intentionally or unintentioanlly interferes with your wiureless network transmissions.
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