Global Information
Technology
Session 2
Presented
by
Dr Allen Brown
Telecommunications and Computer Networks
• These are integral components of almost every
company. Data is a valuable assit.
Networked Enterprise Components
• A simplified computer network will has clients
(users) and a server (a PC with all the apps on)
• The connection between them is the standard is the
swisted pair Cat5, Cat 6 or Cat 7 cable.
• The difference between them is the amount of data
traffic they can carry – Cat 7 carries up to 600Mbps.
RJ45 LAN connector
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• It’s not uncommon to see a server with many of these
cables – patch panel.
• When you added a printer to a network, connect
directly to the server or the router.
• The server software will decide which clinet can
access the printer.
• In an enterprise there will be a LAN administrator
(some of you may find yourselfs as administrators in
the future).
• Their function is to ensure the smooth running of the
LAN.
• Define the range of services provided by the server.
o Web servers: used to store the file and code used
to make up Web pages.
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o Mail servers: stores all email accounts which
clients can access.
o File servers: make files accessable for
downloading and storage to the clients.
• All the apps will be on the server. Very easy to updata
with only one copy which the clients can access.
Types of networks
• There are several configurations of networks
depending on their requirements.
• PAN: Personal Area Network, in the home with
several devices connected together to exchange
data. Low cost
• LAN: Local Area Network, minimum of 2
computers to thousands all within the same
building.
• WAN: Wide Area Network, a network where data
is transmitted over large distance.
o Connecting several LANs together which are at
different locations (global).
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• WLAN: Wireless LAN, a LAN which has provision
for connecting clients using Wi-Fi.
o As you can see in this diagram there is a
Wireless Access Point connecting a LAN and a
WLAN.
o Very similar to a router.
o As you can see in this Netgear R6220 AC1200
smart router, LAN connectors and a WAN
connector in yellow – going to the server.
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o Allows communication with labtops which
these days only have Wi-Fi.
• MAN: Metropolitan Area Network, connecting
LANs with in a 30 mile city.
o Normally use an Internet Service Provider for
the communications channel to connect
several LANs.
o It’s common practice for a university to have
its own MAN connecting the different
departments.
o Also use WiMAX as a wireless technology for
communications of LANs.
o The technology often used is the
synchronous optical network (SONET).
o The OC3 for a MAN can carry 155 Mbps.
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o Multiprotocol Label Switching (MPLS) which
allows a variety of comms technology to be
used.
SAN Options
• DAS: Direct Attached Storage.
o SCSI Small computer system interface
o Block level storage, instead of whole files of
data being transferred, only smaller blocks of
data are used.
o Not easy for Server 1 to access the DAS on
Server 2.
• NAS: Network Attached Storage
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o Acts like a File Server.
o Much slower access that SCSI.
• FC: Fibre Channel
o Found in enterprises.
o Allows fast block level storage which is more
efficient that file level storage.
o Communication between Servers to the FC is
through a HBA.
o Expensive to imprelemt.
• FCoE: Fibre Channel over Ethernet.
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o Much cheaper solution than FC by itself.
o Can be The fibre channel storage can be
accessed directly from the servers through the
FCoE.
o To be found in large enterprises.
• iSCSI: Internet Small Computer System Interface
o Data transfer in IP packets.
o Allow block level access.
o Cheaper solution that previous designs.
o Suitable for a small enterprise.
o Performance is not as good as FCoE.
• VPN: Virutal Private Network, when you extend a
LAN over the internet to a PC in a remote location.
o For a person to share their PC resources with
others.
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o Very useful for a very, very small business
where there is a need to communicate with
customers.
o To set it up, you have to do port forwarding.
Advantages of Network Environment
1. Enhanced communication
• Instant messaging to allow people to see and
talk in real time.
• Send files to other people wherever they are
located globally.
• Access to a vast amount of information
including news and current events.
2. Convenient resources sharing.
• Needed in large companies who share
information and resouces.
• Shared through networks.
3. Easy file sharing
• Sharing data is very importatnt.
• A company may wish to show its current stock
levels with customers.
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• Makes ording from a catalogue easy.
4. High flexibility
• Changes and expansion can be implemented
without disruption – software updates.
• New technology can be introduced to
imporove the speed of communications.
5. Relatively low cost.
• Once a system is in place, the cost of
maintence is relatively low and updates can be
implemented without too much expense.
6. Cost efficienty
• So many competitively costing apps on the
market which can be stored on a server and
accessed by the clients on the network.
7. Memory capacity
• Making files available to clients on the network
is easy to achieve as they are stored on the
network had drives.
• As the need for more memory increases, it’s
easy to add more hard drives without
disrupting the system.
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8. Employment
• In order to maintain computer equipment for
enterprises expert employees are required to
perform this task.
• This offers employment for computer science
graduates who will also be responsible for
upgrading the equipment as the need arises.
Business Uses of Internet
• There is a saying in Silicon Valley,
Here is a desk Here is a Now make a
computer business
• There are huge opportunities for business
enterprises employing the internet.
• There are six phases
1. Identify your market.
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2. Can your provide a service or product for that
market? Have you got the passion to do it?
3. Costing the service or product.
4. Getting the finance to support your start-up, you
will need a convincing spreadsheet.
5. Creating the service or product.
6. Marketing and selling your product or service
using the internet.
Open discussion on
new business opportunities
using the internet
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Distributed Computing
• It is customary to think of a single computer exchanging
data with other computer, but doing its own
processing.
• Alternative concept is to have several computers
processing the same data togeter – distributed
computing.
Grid Computing
• To have several computers in different locations
performing the same mathematical calculations –
executing the same model.
• Example the Navier-Stokes equation,
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[ + ∙ ∇ ] = ∇ − ∇ + ∆
• can be a huge vector with hundreds of elements.
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• This equation is used to model fluid flow, weather,
rocket fuel combustion…
• Normally need a supercomputer to perform the
calculations.
• A cheaper solution is to use a grid of PC working in
parallel.
• Grid computing is a computer network in
which each computer's resources are shared
with every other computer in the system.
• Processing power, memory and data storage
are all common resources that users can
access for specific computational tasks.
• A grid computing system can be as simple as a
collection of similar computers running on the
same operating system.
• Alternatively a more complex networked
systems comprises disparate computer
platforms.
• In the ideal grid computing system, every
resource is shared, turning a computer
network into a supercomputer.
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• With the right user interface, accessing a grid
computing system would look no different
than accessing a local machine’s resources.
• Every computer in the grid would have access
to enormous processing power and storage
capacity.
• There is some interesting work going on in
the University of Antwerp in Belgium.
• They have a PC called Fastra.
• Their PC development is applied to
tomography.
• Four graphics cards containing 8 GPUs as you
can see in the image.
• Needs a beefed-up power supply.
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• It’s made from consumable hardware – off
the shelf components.
• Cost < €4,000
• One hour computation using a PC cluster →
30 seconds.
• GPUs are designed to perform this type of
calculation very efficiently.
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( 21 22 23) ( ) = ( ′)
31 32 33 ′
• It can be used to translate the position and change the
position and shape of an object in 3D space.
• Also rotation and stretching and shearing.
• Every 3D object is made from many little objects like
this one and each needs to be processed.
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GSM Global System for Mobile
• This is a simplified block diagram for GSM.
• Looking into each of these blocks we find.
o BTS – Base Transceiver
System →
o BSC – Base Station
Controller
o OMC – Operations and
Maintenance Centre,
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monitor the performance of the
network.
o MSC – Mobile Switching Centre
o HLR – Home Location Register
o VLR – Visitor Location Register,
used for roaming needs.
o AUC – Authentication Centre,
checking users by the SIM numbers.
o PSTN – Public Switched Network,
land line telephones.
o Frequency bands 900MHz and 1.8 GHz
3G, 4G & 5G technologies
• Technologies for connecting mobiles to the network
(G stand for Generation)
• In addition to voice, other data formats are
transferred, MP3 audio, photos, video and storage.
• Streaming audio and video.
• Generally 4G is faster than 3G and offers more
storage.
• 5G should proide download speeds up to 20 Gbps.
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• The latency time should only be 1 ms.
• Likely to used in self-driving cars.
• 5G will allow more simultaneous connections – the
number of mobiles in the workd is increasing.
VoIP Voice over Internet Protocol
• Using the internet for voice telephony.
• Uses a CODEC to convert speech into packets which are
then sent acorss the internet.
• Much cheaper than internation telephone calls.
• Skype was one of the first.
• The quality (QoS – Quality of Service) varies to how
much trafic there is between source and destination.
• However apps like WhatsApp uses Extensible Messaging
and Presence Protocol (XMPP) for streaming XML data.
• Seems to have superior performace to VoIP.
IPTV Internet Protocol Television
• Delivering television over the internet.
• Streaming media – client can watch material without
waiting.
o Live television
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o Time-shifted television
o Video on demand
• Making big inroads into traditional terrestrial, satellite and
cable TV.
• Many international providers.
• In the UK Netflix is gaining in
popularitym choose any movie you
want to watch !
• To a smaller extend, Amazon is making some headway in
the UK.
• BBC is now under threat from IPTV, its left-wing bias in
reporting news, cannot be relied on as a true unbiased
news media.
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Electronic Commerce Systems
• The internet is now an indispensible tool for e-
Commerce.
• Networked computers are also indispensible for
any size business.
Introduction to e-Commerce
• Broadly defined as the process of buying or
selling of goods or services using an electronic
medium such as the Internet.
• eCommerce refers to the paperless exchange
of business information using the following
ways:
• Electronic Data Exchange (EDI)
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• Electronic Mail (e-mail)
• Electronic Bulletin Boards
• Electronic Fund Transfer (EFT)
• Other Network-based technologies
Features
• Non-Cash Payment: enables the use of credit
cards, debit cards, smart cards, electronic fund
transfer via bank's website, and other modes of
electronics payment.
• 24x7 Service availability: automates the
business of enterprises in the provision of
services to customers. Available anytime,
anywhere.
• Advertising - Marketing: − Increases the reach
of product advertising. Better marketing
management of products and services.
• Increased Sales: Orders for the products
generated anytime, anywhere without
automatically. Boost to existing sales volumes.
• Support: Provides pre-sales and post-sales
assistance leading to better services for
customers.
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• Inventory Management: Automates inventory
management. Reports get generated instantly
as required - easy to maintain.
• Communication improvement: Provides ways
for faster, efficient, reliable communication
with customers and partners.
Potential Problems
• Possible lack of system security, reliability or
standards.
• Many countries do not have a robust network
bandwidth.
• If a company does not have eCommerce –
exclusion from the market.
• Difficulties integrating ecommerce software or
website with existing applications or databases.
Business Models
• Business to business
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• Business to consumer
• Customer to customer
• Consumer to business
• Payments through credit or debit cards or direct
bank transfer.
• Need to have this embedded in the software.
• The use of PayPal.
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• Major concerns – security and scams.
M-Commerce
• Mobile commerce or M-Commerce – buying and
selling using a mobile.
• Downloading an app which you pay for is an
example of M-Commerce.
• When setting up a payment method, could employ
a payment gateway such as PayPal to handle the
process.
• Advantages
o Can handle huge numbers of sales and is easy
to implement.
o People are more inclined to use mobiles than
PC these days.
o Easy for advertises to embed adverts in mobile
data.
o Many people pay for products in shops using
M-Commerce software.
o Becoming a cashless society - Sweden
• Disadvantages
o Security is always a big issue.
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o Loss of moble and the possibility of someone
hacking into it.
o Person to person money exchange requires
paper money – cannot be traced – the Black
Economy – no VAT.
Concept of Internet Banking
• Movement away from using cheques for money
payments.
• Almost all bank transactions can be performed
over the internet.
o Money transferred from employer to
employee’s bank account – tax and National
Insurance deducted using PAYE.
• Customers can access their bank details via their
bank’s website.
• A bank is able to advertise all the services it
provides as customers access their account
details.
• First Direct, part of the HSBC group offer
telephone banking – no high stree banks. All
transactions are effected over the telephone.
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Electronic Payment Systems
• Making an ePayment for goods and services
without the use of paper money.
• Use of smart credit and debit cards
– chip & pin.
• Will accept large amounts of
money transfer – thousands of £ -
used when buying new car.
• Contactless use for purchases under £30.
• In Hong Kong, in common use is
the Octopus card.
• Used for buying everyday
products and services,
transport, food..
• Many shops, have the
facility to credit your
Octopus card – hand
over your HK$ money
and credit is added to your card.
• Word of caution – don’t put too much credit on it,
if lost it’s gone !
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