Information Management

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Information Management
Lecture 4
Technology for Information
Management
Bibliography
 [1] Dave Chaffey, Steve Wood - Business Information
Management : Improving Performance Using
Infomation Systems, 2005, Prentice Hall/Financial
Times, (734 pages)
 [2] Benson V., Tribe K. – Business Information
Management, 2008, Ventus Publishing (83 pages)
 [3] G. Somasundaram, Alok Shrivastava, Eds. Information Storage and Management: Storing,
Managing and Protecting Digital Information, 2009,
Wiley Publishing, Inc (478 pages)
 [4] Wikipedia
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Overview
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Technology infrastructure components
Selecting computer components
Selecting processors
Selecting memory devices
Selecting permanent storage
Selecting output devices
Selecting input devices
Introduction to network technology
Internet technology
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Technology infrastructure (TI)
 TI is the architecture of hardware,
software, content and data used to
deliver information services to
employees, customers and partners.
 The domain of TI can be splited in:
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Organizational TI
Computer system components
Networking and telecommunications links
Inter-organizational TI – the use of Internet
for information transfer
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A five layered model of TI [1,
pg. 118]
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The TI is often implemented using a client-server model.
The client–server model of computing is a distributed application
that partitions tasks or workloads between the providers of a resource
or service, called servers, and service requesters, called clients.
The word client can name a physical person or a software to access
the server in the service of the physical person or of another software
The server can name a hardware used as storage or can provide
applications for the clients. Also it can name a software used in a
client-server manner for providing services and storage to clients.
So client-server refers to either the software model also to hardware
or/and persons from the real world.
TI addresses both.
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Different types of servers
[1,118]
 Web server. Manages http requests from client and acts
as a passive broker to other servers. Returns or serves
web pages.
 Merchant server. This is the main location of the
application logic and integrates the entire application by
making requests to the other server components.
 Personalization server. Provides tailored content – may
be part of commerce server functionality.
 Payment commerce server. Manages payment systems
and secure transactions.
 Catalogue server. A document management server used
to display detailed product information and technical
specifications.
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 CRM server. Stores information on all customer
contacts.
 ERP server. Required for information on stock
availability and pricing from the customer. Will
also need to be accessed for sales order
processing and histories.
 Logistics for distribution will also be arranged
through the ERP server.
 Network server. Used to manage access of
employees to the company network.
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 To manage the load of each server
one ore more physical machines will
be used.
 For very large loads we have server
farms with hundreds of servers.
 An important decision in designing an
technology infrastructure (TI) is to
decide what is to be handled by the
servers and what by the clients.
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What would the server and the
client handle
 Data storage should be
predominantly on the server
 Query processing - on the server
 Display of graphics and text – on the
client
 Application logic – on the client or on
the server
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Three-tier client-server
architecture [1, 120]
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Types of client computers
 Terminals
 PC:
 Desktop
 Laptop
 Handheld – PDA (personal digital
assistant)
 Windows terminal or network computer
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Types of server computers
 Mainframes, mini-computers, microcomputers – for
small companies
 For large companies:
 Blade servers - Compact ‘high-density’ servers
comprising microprocessors and memory on a single
circuit board to optimize the use of physical space.
 Clusters of servers for increased stability and
performance
 Storage area network (SAN) – clusters + networked
storage devices
 Grid computing - the combination of computer
resources from multiple administrative domains to
reach a common goal [4]
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Types of server computers (2)
 Cloud computing - the delivery of computing as a
service rather than a product, whereby shared
resources, software, and information are provided to
computers and other devices as a utility (like the
electricity grid) over a network (typically the
Internet). [4]
 Mainframes – large computers capable of hosting
multiple OS which provide virtualization and hot swap
capabilities. Better cost performance than PCs in
large organizations.
 Mini-computers. For example for web hosting.
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Computing architectures
 Centralized computing - a single mainframe or minicomputer performs processing and provides storage for
many users. Clients are text terminals or more
sophisticated.
 Personal computing – individual PCs are user for storage
and performing user tasks
 Distributed computing – clients are connected with
multiple servers
 Network computing – similar to centralized computing
but with more performant client
 Peer-to-peer (P2P) computing – each computer can be
used as a server or a client at the same time
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Main components of a PC [1,
127]
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Selecting a processor (CPU)
 The factors for selecting a CPU are:
 Manufacturer. Most known Intel and AMD.
 Processor architecture. RISC, multicore
processors, multiprocessor computers
 Clock speed. As the clock speed increases so
does the MIPS (millions of instructions per
second).
 System bus, chipset and motherboard. On
the motherboard the system bus frequency
(in MHz) and the chipset can affect the
performance of the PC.
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Other processors
 There are other important
microprocessor that can affect the
PC’s performances.
 Graphics and audio processors are a
good example. They are located on
the motherboard or on separate
graphic card respectively audio card.
 NIC (network cards) are also
equipped with microprocessors
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Memory devices
 Types of storage:
 Volatile storage -RAM
 Permanent storage – ROM, HDD
 ROM stores the BIOS (binary input
and output system) which controls
the hardware. It doesn’t affect the
performance of the system, being
standard PC component.
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 RAM (random access memory) holds the OS,
the running programs and their data. It is
volatile. It is supplemented with virtual
memory (swap file or page file) located on the
HDD.
 Few RAM determines high use of the virtual
memory which is slower and thus decreases
performances.
 If RAM and virtual memory are full, the PC
stops working or is very slow.
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Permanent storage
 Magnetic storage: HDD, floppy disks
 Optical storage: CD, DVD – Read
Only or Rewritable
 Tape storage: magnetic tape – high
capacity, used for backup, slow speed
 Solid state memory devices – flash
RAM
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Factors for selecting storage
devices and media
 Capacity of the device or medium
 Speed of reading and writing:
magnetic media are the fastest, then
optical media, then tape media
 Cost of device
 Cost of removable media
 Need for permanent or removable
media
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Factors for selecting output
devices: monitors
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Type of the monitor: CRT, LCD
Size
Resolution
Number of colors supported
Dot pitch (size of one pixel on the
screen)
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Factors in selecting printers
 Type of printer: dot matrix printer, plotter
(used for CAD), inkjet printer, laser printer
 Paper sizes supported, orientation
 Postscript or not
 Number of pages printed per minute (ppm)
 Capacity of the tonner
 Resolution – in dpi (dots per inch) at least 600
dpi, and 1200 for high resolution
 Number of colors supported
 Price
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Selecting input devices
 For selecting the mouse and keyboard
– select ergonomic models
 For selecting scanners – the ones that
protect the eyes
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Network technology
 Computer network - A communication system that
links two or more computers and peripheral devices to
enable transfer of data between these computers [1, pg
142].
 LAN (local area network) – a computer network spread
on a small area, generally a building or an office.
 WAN (wide area network) – a computer network
covering a large area, eventually the whole Internet.
 Wireless networking – LAN using wireless media
 Bluetooth – wireless technology for short range data
transmission
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 ISDN connection (integrated services digital network) –
communication through a phone line using two separate
channels: one for data, the other for voice)
 ADSL (asymmetric digital subscriber line) communication through a phone line where the
download data transfer rate is higher to the upload one.
Also known as broadband services
 Leased line – a line of communications that’s used
exclusively by the company that has leased it
 Secure virtual private network (VPN) – encrypt the
data transmitted through the regular communications
chanels
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 WI-FI – high-speed wireless LAN.
 Wi-FI hotspot – location where
someone can connect freely to the
Internet using a laptop equiped with
wireless technology
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Telecommunications
components
 Modem (modulator-demodulator) allows connection to
Internet through a phone line, eventually using a ISDN
or ADSL line. Speed is measured in baud or bits per
second (bps). Standard modem has 56.6 kbps
 Hub or switch – equipment that is used to connect
more computers using Ethernet cables
 Bridge and router – connect different LANs or PCs.
They offer a WAN line through which the LAN can
connect to the Internet. Eventually are equipped with a
firewall for data protection.
 Repeater – amplifies the signal to increase the distance
of transmission. Can be used for LANs with high
dispersion in space to connect distant points.
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Internet technology
 TCP/IP (Transmission Control Protocol) is a transportlayer protocol that moves data between applications. The
Internet protocol is a network-layer protocol that moves
data between host computers [1, pg. 150]
 The data that is transmitted through the TCP/IP protocol
is broken into packages.
 IP address – a unique numerical address of a computer
 HTTP protocol – protocol of communication between web
browsers and web servers.
 URL (uniform resource locator) – web address of pages.
It contains also the protocol used to access that page.
Ex. http, ftp
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 HTML (hypertext markup language) – language that
describes the web pages. It ensures that all pages are
rendered the same not depending on the web browser
used.
 XML (eXtensible Markup Language) – language used to
include data (e.g. databases) on the Internet. Since it
has a lot of tags, it is better intended for machine
reading than human reading. The DTD (document type
definition) defines the structure of a certain XML file.
 RDF (resource definition framework) – an element of
HTML intended to facilitate standardized metadata.
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 EDI (Electronic data interchange) – The exchange, using
digital media, of structured business information,
particularly for sales transactions such as purchase
orders and invoices between buyers and sellers [1, pg.
144]
 RossetaNet is a consortium of many of the world’s
leading information technology, electronic components
and semiconductor manufacturing companies working to
create, implement and promote open e-business process
standards [1, pg. 162].
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