Presentation on theme: "LN-3: Technologies for Information Management"— Presentation transcript:
1 LN-3: Technologies for Information Management ITECH 1005/5005: Business Information SystemsLN-3: Technologies for Information ManagementDr Zhaohao SunGSITMS, University of BallaratUpdated on by shortening from 77 slides to 71 slides.Updated on by shortening from 71 slides to 59 slides and also based on Chaffey (2011)
2 Objectives and Outcomes After studying this chapter, the students should be able toExplain the relationship between software, hardware and communications components of information systemsEvaluate the suitability of different technology components for information managementManagement issuesHow do we select the appropriate technology for our organization?What is the meaning and relevance of different technology standards associated with the Internet?
3 Why we need to understand Hardware Talking to suppliers about solutionsSelecting the most cost-effective solutionsTroubleshooting our own ‘kit’Reducing the total cost of ownership of hardware (See also Chapter 11)Techno BabbleIn 2003, IT recruitment consultant Computer People conducted a survey into the extent of the problem of IT jargon. 1,000 office workers across various industries were surveyed to examine perceptions of IT personnel and to explore how communication between IT professionals and their non-IT colleagues could be improved.Over two thirds (67%) of office workers said they felt 'bewildered' and 'inadequate' due to not understanding IT professionals' 'tech jargon'.Over half (56%) of those surveyed said that IT professionals 'speak another language' with two fifths (40%) saying that they feel IT staff are unaware of the confusion that tech jargon causes.
4 Technology Infrastructure Components Infrastructure includes the architecture of the networks, hardware and software.Infrastructure can be considered to include the data and documents accessed through e-business applications.Chaffey 2011:98There are four diffferent. Organisational technology infrastructure. Includes different types of computer systems2. Computer system components. Different parts of PCs and other systems3. Networking and telecommunications links. Linking information systems4. Inter-organizational technology infrastructure. Standards used to support e-business between partners
5 Technology Infrastructure Model Figure 3.1 A five-layer model of technology infrastructure (Chaffey 2011: 99)Source: Adapted from Chaffey (2004)
6 Client/server Architecture The client/server architecture consists of client computers such as PCs sharing resources such as a database stored on more powerful server computers. Processing can be shared between the clients and the servers.A client is an end-user computerA server is a computer that provides services such as storage or applications to other client computersMiddleware is software used to facilitate communications between business applicationsClient/server architecture is significant since most modern networked information systems are based on this structure.Chaffey 2011:99-100Client/server modelThere are many different servers
7 Three-tier client-server architecture There are also many different client computers.Figure 3.2 A typical three-tier client server architecture Chaffey 2011:101
8 Reasons for Client-Server Distributes processing potentially giving better performanceNot vitally dependent on central mainframeEnables local data storage for convenienceEmpowers end-users to develop their own applicationsEnables remote working, e.g. sales representativesChaffey 2011:99-101Problems to be managed by client-serverCost of ownershipInstabilityPerformanceLack of user focusLack of control of locally developed applications and data – for example, is data on local hard-disk backed up
9 Different forms of Clients Desktop – system unit is horizontal, vertically in a tower or mini tower configuration.Portable or Laptop.Handheld.Windows terminal or network computer.Figure 3.5 The first Personal ComputerSource: Rune’s PC Museum (http://pc-museum.com/rcm-001.jpg)Figure 3.6 A personal digital assistant (PDA)Source: Hewlett-Packard Company, Inc., Palo Alto CA (www.hp.com)Chaffey 2011:Also call Client computers
10 Alternative Computing Structures Figure 3.7 Five alternative computing architectures Chaffey 2011:106Source: BIM
11 Developments in Server types Blade servers.Clustering storage area network (SAN) – Server clustering is used to connect and manage networked storage devices.Grid computingMainframesMini-computersBlade servers – Compact ‘high density’ servers comprising microprocessors and memory on a single circuit board.Clustering – Servers are connected to increase stability and performance. If one server fails, another will take over, if there is a high load then this will be shared between servers.Storage area network (SAN) – Server clustering is used to connect and manage networked storage devices.Grid computing – The need for powerful servers is reduced by this approach which shares the power of client machines to solve computational problems – the clients are effectively joined to become a powerful server. The best known application of grid computing is SETI (Search for Extraterrestrial Intelligence (http://setiathome.berkeley.edu)) in which over 5 million people are sharing unused processor time of their PCs in the search for signals from outer space.Mainframes – Mainframes are still widely used in large organizations. Can deliver a better cost/performance ratio than PCs in a large organization.Mini-computers – Likewise, mini-computers such as the IBM AS/400 are still widely used for the cost/performance and stability they bring to businesses.
12 A typical e-commerce systems architecture for an e-tailer Source: Chaffey (2002)
13 The Main components of a PC Figure 3.6 The main components of a PC (Chaffey 2011:110)Source:
14 A Processor and selection The processor of a computer is so-called since it processes instructions supplied by the program code within the operating system and applications software.The “Brain” of the PCSelection criteria for ProcessorsManufacturer.Processor architecture.Clock speed.System busChaffey 2011:111An analogy with the human brain is often made since it controls the other computer components in the same way the brain controls the other parts of the body.Another analogy is with the driver of a vehicle who responds to various inputs to control the car.But neither the brain nor a human controlling a vehicle are really analogous to the processor working together with systems and applications software.Manufacturer.Today, the two main PC processor manufacturers are Intel and Advanced Micro Devices (AMD). Other manufacturers such as Hitachi and Motorola make processors for other types of computer.2. Processor architecture. See next slide.3. Clock speed. TThe clock speed gives an indication of how fast a chip can process instructions. See next slide.4. System bus, Chipset and motherboard.The microprocessor is only one part of a wider range of chips known as a chipset which is located on the motherboard – a large piece of circuitboard inside the computer. Intel has many different chipset and motherboard combinations.
17 ATI Graphics Video Card Figure 3.8 ATI Radeon 9800 graphics card with 128 Mb RAM(Chaffey 2011:112)
18 MOOR’S Law (Gordon Moor, 1965) He is a co-founder of IntelFigure 3.9 Moore’s LawSource:
19 RAM - Computer memory is used to store data and programs. There are two types of computer storage. Temporary or volatile storage where data is only saved when a device is switched on and permanent storage where the data is saved even when a device is powered down.Temporary storage is best known through the acronym RAM, standing for Random Access Memory. RAM is used to store the operating system, applications and current data or documentation and is linked closely to the processor to which instructions and data are supplied from RAM.RAM is similar to our short term memory – it is used for issues we are currently thinking about.Figure 3.12 RAM (Source: Kingston Technology Company, Fountain Valley, California (Chaffey 2011:114)-
20 Read Only Memory (ROM)Each computer also contain Read Only Memory or ROM which is permanent storage which is used to store the BIOS which is activated when a computer is first switched on before the operating system is loaded from the hard-disk or other permanent media.When you switch a PC on, the first text screen will always refer to the BIOS (Binary Input and Output System) loading.The BIOS is effectively constant; but it can be upgraded if required. This form of ROM is a standard component on each computer and does not affect the performance of the system, so it is not specified in PC purchase.
21 Storage CapacitiesByte – made up of 8 bits used to represent a single character or digitKilobyte – 1,024 BytesMegabyte – 1,024 KilobytesGigabyte – 1,024 MegabytesTerabyte – 1,024 GigabytesChaffey 2011:114
22 Bits and Bytes - 1 (eight bits, can represent one digit or character) Storage capacityApproximate bytesPower of 2Exact BytesByteExactly 1 byte-1 (eight bits, can represent one digit or character)KilobyteA thousand bytes2101,024MegabyteA million bytes2201,048,576 bytes (1,024 Kb)GigabyteA thousand million bytes2301,073,741,824 (1,024 Mb)TerabyteA trillion bytes2401,099,511,627,776 bytes1,024 Gb)
23 Understanding Storage Capacities Label for volume (size)?GigabyteApprox numeric amount (bytes)1,000,000,000Exampledata amount:A database for a large companyA database for a small companyA high resolution photoA low resolution photoA characterExample storage amount:1 ?bcapacity server120 ?bhard disk512 ?b MemoryOld style720 ?b100 ?b to store numbers in mobile phoneActivityComplete the table below filling in the gaps shown by ?Label for volume (size): Byte, Terabyte, Kilobyte, MegabyteNumeric amount: 1, 1,000,000:1,000,000,000,000 1,000 (Chaffey 2011:115)
24 Why RAM affects system performance Figure 3.13 The relationship between Virtual Memory and RAM (Chaffey 2011:115)
25 Permanent StorageNon-volatile storage – the data is retained after the hardware is ‘powered down’. Some say permanent storage is equivalent to our long-term memory.Storage devices:The main media types for permanent storage are magnetic, optical, tape and solid-state. The media may be readily removable from the computer or it is a fixed part of the system.Permanent storage is used to store the operating system, applications and data. Unlike RAM, the storage is persistent or non-volatile storage – the data is retained after the hardware is ‘powered down’. Some say permanent storage is equivalent to our long-term memory. But the human analogy breaks down since these memories are not retained when we are ‘powered down’!There are a wide variety of permanent storage devices and these can be classified according to the type of storage media and the form of the storage device. The main media types for permanent storage are magnetic, optical, tape and solid-state. The media may be readily removable from the computer or it is a fixed part of the system.
26 Hard Disk Drive, DVD Writer. Memory Stick Figure 3.16 Memory key or stick (Chaffey 2011:120)Figure 3.14 Hard disk drive (Chaffey 2011:117)Figure 3.15 Optical drive – a DVD Rewriter (Chaffey 2011:120)
27 Types of Optical Storage Read-only – traditional CDs and DVD used for music and film.Recordable (denoted by CDR and DVDR) – The media can be written to, but once they reach their capacity space cannot be cleared by deleting existing files.Rewritable (denoted by CDRW and DVDRW) – the media can be written to repeatedly.CDs can hold around 640 to 700 Mb.DVDs can hold either 4.7 or 7.95 Gb depending on whether they are double or single-sided.Chaffey 2011:119
28 Selecting Storage Media Capacity of device or media.Speed of reading and writing media.Cost of device.Cost of removable media. This is a relatively low cost compared to the cost of the device.Need for permanent or removable media. In some cases where a removable device is needed such as removable hard disk then this can add to the cost of the device.Chaffey 2011:120
29 Output DevicesThere are two main output devices for a computer system which are used to interact with applications and data.The first is the monitor or display which is, of course, used for interacting with the system, the second is the printer which is used for keeping hard copy.Output devices Used for viewing outputs from a systemHard copy Printed output from a system, distinct from soft or electronic copy
30 Selecting a Monitor Form: Text (VDU) raster/graphics (vector) based Resolution (pixels)VGA 640 by 480SVGA 800 by 600 (design for many web sites)XGA 1024 by 768Size: 14”, 15”, 17”, 21”Colour depth: 16, 256, 15 million etc.Choose a good graphics card which enables higher resolutions than those chosen above.See CRT Monitor, Fig 3.17, Chaffey 2011: 122
31 Flat Screen MonitorFigure 3.16 A flat-screen monitor (Chaffey 2011:122)
32 Monitor Selecting Criteria TypeCharacter, graphics (raster) or graphics (vector) basedLaser printer vs InkjetResolutionMeasured in dots per inchColour depthThroughputMeasured in pages per minute
34 Laser PrinterFigure 3.18 Xerox Docutech laser printer with a capacity of 500,000 sheets per month (Chaffey 2011:123)
35 Data Input DevicesData is captured or input by different hardware tools or devices that rely on movement, light or sound e.g.Keyboard, mouseScannerBarcode readerVoice recognitionFinger print readers for securityDirect Digital Input(Chaffey 2011:125)Microsoft Wireless Desktop (Chaffey 2011:126)
36 Selecting Input Devices Mice and keyboard are commodities, so cost reduction is key. But:Can cause repetitive strain injury in staff if poor quality (and other issues of ergonomics)Wireless keyboards and mice can appear neater, but require batteries, so more often used at home rather than business(Chaffey 2011:125)
37 Computer Network Computer network A communication system that links two or more computers and peripheral devices to enable transfer of data between these computers.The purpose of a computer network is to transfer data between different computers or hardware devices.The client/server model introduced earlier requires a computer network to transfer data between the client and server computer. The server may also be connected to other hardware devices such as a network printer or a backup system using a network.(Chaffey 2011:127)
38 LAN’s and WAN’s Local-area network (LAN) A computer network that spans a limited geographic area such as a single office or building.Wide-area networkComputer networks covering a large area which connects businesses in different parts of the country or different countries.Computer networks are constructed on different scales. Small-scale networks known as local-area networks (LANs) can be set up in an office, a small business or even at home. Larger-scale networks which may span a city, country, the world or space are known as wide-area networks. These effectively link together different LANs.(Chaffey 2011:127)
39 Network advantages/disadvantages (Chaffey 2011:128) 1. Facilitates sharing of information1. Organization becomes overdependent on networks for access to information and applications2. Reduces duplication of information2. Cost of initial setup, usage and maintenance3. More rapid information transfer including real-time information access3. Reduced security of information as information is exposed to increased risk of internal and external access, modification and deletion4. Reduces hardware requirements through sharing of devices4. Can facilitate information overload as s and documents are more easily distributed5. Enables software to be managed centrally and reduces need for local copies of software6. Assists in information security by requiring log-in for access to certain data7. Enable transformation of business through e-business applications8. The Internet provides potential to reach new international markets or new customer groups at a relatively low cost
40 Different forms of guided media Integrated services digital network (ISDN) An ISDN telephone line provides two separate ‘channels’ allowing simultaneous voice and data transmissions.Asymmetric Digital Subscriber Line (ADSL) services makes use of existing telephone lines to provide very high data transfer rates. ADSL is known as asymmetric since download data transfer rates are different (higher) than upload rates.Wi-Fi (Wireless fidelity): A high-speed wireless LAN enabling wireless access to the Internet for mobile, office and home users.Leased lines or secure virtual private networks (VPNs) with higher speed access using the T1 standard are used by larger organizations.(Chaffey 2011:128-9)Data transmitted digitally over phone lines can use a range of techniques.Digital telephone exchanges support an integrated services digital network (ISDN) standard that allows data transfer rates that are up to five times faster than the traditional POTS (‘Plain Old Telephone Service’). An ISDN telephone line provides two separate ‘channels’ allowing simultaneous voice and data transmissions.The introduction of Asymmetric Digital Subscriber Line (ADSL) services makes use of existing telephone lines to provide very high data transfer rates. ADSL is known as asymmetric since download data transfer rates are different (higher) than upload rates.Such high speed services are known as broadband services. When used to access the Internet they make practical the transmission of larger volumes of data used for downloading music, for example, see On Demand Distribution (www.ondemanddistribution.com) which is used to feed many music download services in Europe or streaming video (see for example BBCi Broadband,Leased lines or secure virtual private networks (VPNs) with higher speed access using the T1 standard are used by larger organizations.LAN: = local area network
41 Transmission SpeedThe speed at which data can be transferred from A to B is governed by the channel capacity, which is measured in bits per second (bps). Transmission of a single bit in a second is equivalent to one baud, a binary event.Rates are usually measured in terms of thousands of bits/second (Kb/sec), millions of bits/sec (Mb/sec) or billions of bits/sec (Gb/sec).A general term often used for describing capacity is bandwidth, which is a measure of capacity given by the difference between the lowest and highest frequencies available for a given medium.
42 Internet Connection Speeds POTS – 56Kb/sec modemISDN – 256 or 512 Kb/secADSL – First introduced mainly at 512 Kb/sec, but 256 Kb/s, 1 Mb/s and 2 Mb/s options now commonMonthly capacity may be capped, e.g. 1, 15 GbSatellite – similar to ADSLUpload and download maximum figures differ
43 Communication Components Modem Modulator-demodulator used to convert data between digital and analogue form when transmitting data over telephone linesHubs Used to connect groups of computers to a networkBridges and routers Device used to connect networks and control the flow of data between themFirewall Hardware used to increase security of part of a network through preventing unauthorized access from beyond the networkRepeatersDevice used to increase efficiency of transmission over long distances(Chaffey 2011:129)
44 EDIElectronic data interchange (EDI) is the computer-to-computer exchange of structured data, sent in a form that allows for automatic processing with no manual intervention. This is usually carried out over specialist EDI networks. DTI (2003)Chaffey 2011:130Activity: Write down all the different types of hardware and software involved from when a user types in a web address such as to the web site being loaded
45 Internet TechnologyFigure 3.22 Physical and network infrastructure components of the Internet(Chaffey 2011:131)
46 Internet TimelineFigure 3.23 Internet timeline (Chaffey 2011:132)
47 Information exchange between web-browser and web-server Figure 3.24 Information exchange between a web browser and web server(Chaffey 2011:134)
48 TCP/IP ProtocolFigure 3.26 The TCP/IP Protocol (Chaffey 2011:136)
49 World Wide WebThe World Wide Web, or ‘web’ for short, provides a standard method for exchanging and publishing information on the Internet.If we take the analogy of television, then the Internet is the equivalent to the broadcasting equipment such as masts and transmitters, and the World Wide Web is equivalent to the content of different TV programmes.The medium is based on standard document formats such as HTML (Hypertext Markup Language)Chaffey 2011:133
50 HTM and HTMLHTML (Hypertext Markup Language)A standard format used to define the text and layout of web pages. HTML files usually have the extension .HTML or .HTM.XML or eXtensible Markup Language: A standard for transferring structured data, unlike HTML which is purely presentational.HTML code<P> This text is <B>bold </B></P><P>This text is <I>italic</P><P>This text is <U>underlined</U></P>In browser:This text is boldThis text is italicThis text is underlinedHTML (Hypertext Markup Language) A standard format used to define the text and layout of web pages. HTML files usually have the extension .HTML or .HTM.XML or eXtensible Markup LanguageA standard for transferring structured data, unlike HTML which is purely presentational.
51 HTML CodeHTML code<A HREF="index.htm"> Go to home page </A><BR><A HREF="http://www.bbc.co.uk ">Go to the BBC web site</A>Browser:Go to home pageGo to the BBC web site
52 URL’s and Domain NamesURL (Universal Resource Locator): a web address used to locate a web page on a web server.Web addresses are structured in a standard way as follows:What do the following extensions or global top level domains stand for?.com.co.uk, .uk.com.org or .org.uk.gov.edu, .ac.uk.int.net, .biz, .infoChaffey 2011:133
53 Metadatadefinition of the structure and content of a collection of data or document. ‘Data about data’.HTML has a limited capability for describing documents through HTML meta-tags. These are presented at the start of the document in the header area.Chaffey 2011:140Metcalfe’s law was first stated by Bob Metcalfe, who was co-founder and former chief executive of networking company 3Com. He was reputed to have said in presentations made for the company:‘The power of the network increases exponentially by the number of computers connected to it. Therefore, every computer added to the network both uses it as a resource while adding resources in a spiral of increasing value and choice.’
55 XML Metadata Example <rdf:Description> <dc:title>E-business and E-commerce Management</dc:title><dc:creator>Dave Chaffey</dc:creator><dc:format>Book</dc:format><dc:identifier>ISBN </dc:identifier></rdf:Description>Examples of XML ApplicationsIntel In 2003 Intel publicly announced plans to end EDI business processes company-wide by 2006 and rely on RosettaNet as a key enabler to their future e-business strategy.To date, Intel has implemented RosettaNet as the company’s standard for business-to-business integration with 89 of its trading partners in 17 different countries.The company processed more than 10 percent of its revenues and supplier purchases in 2002 using RosettaNet e-business technology standards. Intel transacted more than US$3 billion in customer orders and US$2 billion in supplier purchases on RosettaNet, increasing by approximately seven times the total amount of business processed via RosettaNet connections in one year.Nokia RosettaNet is the primary enabler for Nokia’s system-to-system integration with its demand supply network allowing the company to automate the extreme challenge of processing over 10 million components per hour. Currently, the major business groups within Nokia, including suppliers, contract manufacturers, logistics and customers, are involved in RosettaNet implementations across the globe.Sony In 2002, Sony centralized its vendor managed inventory system (VMI) by connecting with over 90 suppliers using the RosettaNet standard. Like Intel, Sony intends to replace EDI with RosettaNet. Sony’s EDI replacement will initially cover their mass-production procurement, but in the longer term RosettaNet will replace EDI for all aspects of Sony’s business.
56 The Wireless InternetWireless connection to the Internet is possible in several different formsWAP internet access from mobile phonesWireless Application Protocol (WAP) WAP is a technical standard for transferring information to wireless devices, such as mobile phones.3G Third generation of mobile phone technology with high speed data transfer enabling video calling.i-Mode A mobile access platform widely used in Japan that enables display of colour graphics and content subscription services.Chaffey 2011:149
57 SMS MessagingSMS: short message service, is the formal name for text messaging, commonly known as “texting”SMS is a simple form of that enables messages to the transferred between mobile phones.Over 3 trillion text messages were sent worldwide in 2009Texting has proved useful for business in some applicationsChaffey 2011:151
58 SummaryExplained the relationship between software, hardware and communications components of information systemsEvaluated the suitability of different technology components for information management