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TELECOMMUNICATION & NETWORK
APPLICATIONS
PART 1
LEARNING OBJECTIVES
Benefits of telecommunication networks in business
Networking basics: Architecture, Topology, Protocols,
Media
Network applications
COMPUTER NETWORKS
Connected computers:
Work together
Are interdependent
Exchange data with
each other
SIZE OF COMPUTER NETWORKS
Home computer network
Global computer network
National computer network
MOBILE COMPUTING
The characteristics, mobility and broad reach, create five
value-added attributes that break the barriers of geography
and time:
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Ubiquity : regardless of user’s location
Convenience
Instant connectivity
Personalization
Localization of products and services
Ubiquity: mobile device can provide information and
communications regardless of user’s location.
Convenience and Instant Connectivity: Internetenabled mobile device makes it easy and fast to
access the Web, intranets, and other mobile devices
without booting up a PC or placing a call.
Personalization: information can be customized and
sent to individual consumers (e.g., as a
short message service).
Localization of products and services: knowing a
user’s location helps companies advertise
their products and services.
BENEFITS OF A
CONNECTED WORLD
Networks offer many advantages for a business including
• Sharing resources
• Providing opportunities
• Reducing travel
Before networks, transferring data between computers was
time-consuming and labor intensive.
People had to physically copy data from machine to machine
using a disk.
Networks offer many advantages for a business including:
Sharing resources
Providing opportunities
Reducing travel
There have been many network security problems - networks
are a tempting target for mischief and fraud
An organization has to be concerned about…
Proper identification of users and authorization of network
access
The control of access, and the protection of data integrity
CHALLENGES OF A CONNECTED
WORLD
Networks have created a diverse, yet globally
connected world by eliminating time and distance,
networks make it possible to communicate in ways
not previously imaginable
Even though networks provide many business
advantages, they also create increased challenges
in
• Security
• Social, ethical, and political issues
BENEFITS OF
BUSINESS MOBILITY
Enhance mobility
Provides immediate data access
Increases location and monitoring
capability
Improves work flow
Provides mobile business opportunities
Provides alternative to wiring
CHALLENGES OF
BUSINESS MOBILITY
Protecting against theft
Protecting wireless connections
Preventing viruses on a mobile device
Addressing privacy concerns with RFID
(Radio Frequency Identification) and LBS
(Local Base Service)
TYPES OF NETWORKS
A computer network is a system that connects computers via
communications media so that data can be transmitted among
them.
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Local area networks
Wide area network
Value-added network
Enterprise network
Local area networks: connects two or more devices in a
limited geographical region.
Wide are network: networks that cover large
geographical areas.
Value-added network: a type of wide area network that
are private, data-only networks managed by third parties
that provide telecommunication and computing services
to multiple organizations.
Enterprise network: the entire network of an
organization, usually consisting of multiple local area
networks and multiple wide area networks.
LOCAL AREA NETWORK
WIDE AREA NETWORK
ENTERPRISE NETWORK
HUMAN
COMMUNICATION
COMPUTER
COMMUNICATION
Senders and Receivers
There must a be a sender and a receiver with something
to share via a message to facilitate communication
Communication Medium (Channel)
A medium must exist between the sender and receiver
over which the message travels (e.g., a cable)
Protocols
Procedures, rules, or standards must be followed by
computers when sending or receiving data
CODING, SENDING, DECODING
THE TELECOMMUNICATIONS
SYSTEM
A telecommunications system consists of hardware and
software that transmit information from one location to
another.
TYPICAL TELECOMMUNICATIONS
SYSTEM
ANALOG AND DIGITAL SIGNALS
COMMUNICATIONS
PROCESSORS
Modem – Modulation/Demodulaion: covert analog signals to
digital signals and vice versa
Multiplexer – a single channel can carry data simultaneously
from many sources
Front-End Processor – mainframe communicates with many
computers
Modem: device that converts
digital signals to analog signals and
vice versa.
Multiplexer: an electronic device
that allows a single
communications channel to carry
data transmissions simultaneously
form many sources.
Front-End Processor: a specialized
computer that manages all routing
communications with peripheral
devices.
Modems
Digitizing (change info to bits 0-1)
Modem Modulator/Demodulator -(code/decode
digital/analog)
BASIC NETWORKS
PERSONAL AREA NETWORK
Personal area networks (PAN) - Provide
communication over a short distance that is
intended for use with devices that are
owned and operated by a single user
Bluetooth - Wireless PAN technology that
transmits signals over short distances
between cell phones, computers, and other
devices
WIRELESS LAN
Wireless LAN (WLAN) - A local area network that
uses radio signals to transmit and receive data
over distances of a few hundred feet
Wireless fidelity (Wi-Fi) - A means by which
portable devices can connect wirelessly to a local
area network, using access points that send and
receive data via radio waves
WIRELESS MAN
Wireless MAN (WMAN) - A metropolitan area network that
uses radio signals to transmit and receive data
WIRELESS MAN
Worldwide
Interoperability for
Microwave Access
(WiMAX) - A
communications
technology aimed at
providing high-speed
wireless data over
metropolitan area
networks
WIRELESS WAN CELLULAR
Wireless WAN (WWAN) - A wide area
network that uses radio signals to transmit
and receive data
WIRELESS WAN CELLULAR
Smart phone - Offer more advanced
computing ability and connectivity than
basic cell phones
3G - A service that brings wireless
broadband to mobile phones
Streaming – A method of sending audio and
video files over the Internet
WIRELESS WAN SATELLITE
Satellite - A space station that orbits the
Earth receiving and transmitting signals
from Earth-based stations over a wide area
NETWORK BASICS
Networks are differentiated by the following:
• Architecture - peer-to-peer, client/server
• Topology - bus, star, ring, hybrid, wireless
• Protocols - Ethernet, Transmission Control Protocol/Internet
Protocol (TCP/IP)
• Media - coaxial, twisted-pair, fiber-optic
PROTOCOLS
Protocol - A standard that specifies the format of data as well
as the rules to be followed during transmission
Interoperability - The capability of two or more computer
systems to share data and resources, even though they are
made by different manufacturers
ETHERNET
Ethernet - A physical and data layer
technology for LAN networking
TRANSMISSION CONTROL
PROTOCOL/ INTERNET PROTOCOL
TCP/IP applications
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File transfer protocol (FTP)
Simple mail transfer protocol (SMTP)
Hypertext transfer protocol (HTTP)
Simple network management Protocol (SNMP)
NETWORK PROTOCOLS
Rules or procedures used to transmit and
receive data
Specify:
• Connection of computers to the network
• Error checking
• Data compression
• Signal of finished transmission
• Signal of received message
Examples of protocols:
• OSI, TCP, IP, UDP, IPX, SPX, etc.
THE FOUR LAYERS OF THE TCP/IP
PROTOCOL
ARCHITECTURE
There are two primary types of architectures
• Peer-to-peer (P2P) network
• Client/server network
PEER-TO-PEER
NETWORKS
Peer-to-peer (P2P)
network - Any
network without a
central file server
and in which all
computers in the
network have access
to the public files
located on all other
workstations
CLIENT/SERVER
NETWORKS
Client - A computer that is designed to request information from
a server
Server - A computer that is dedicated to providing information in
response to external requests
• Client/server network - Model for applications in which the bulk
of the back-end processing takes place on a server, while the
front-end processing is handled by the clients
CLIENT/SERVER
NETWORKS
Network operating system (NOS) - The operating
system that runs a network, steering information
between computers and managing security and users
Packet-switching - Occurs when the sending computer
divides a message into a number of efficiently sized
units called packets, each of which contains the
address of the destination computer
Router - An intelligent connecting device that
examines each packet of data it receives and then
decides which way to send it onward toward its
destination
CLIENT/SERVER
NETWORKS
PACKET SWITCHING
PACKET SWITCHING
ROUTER
ROUTER
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