Communication Trends and Applications

Published on December 2016 | Categories: Documents | Downloads: 40 | Comments: 0 | Views: 298
of 125
Download PDF   Embed   Report

Comments

Content

Chapter
Communication Trends and
Applications

© N. Ganesan, Ph.D. , All rights reserved.

Chapter Objectives
• Describe the status of information
communication past and present
• List the factors that led to the growth of
computer communications
• Outline a few sample communication
applications
• Discuss the evolution of Wide Area
Network communications and its current
convergence to digital technology

Module

Information Communication
Past and Present

© N. Ganesan, Ph.D. , All rights reserved.

Communication in the Past
• Known as Data Communications
– Mostly concerned with alphanumeric
data

• A highly specialized topic
• Focus
– Mainframes
– Analog telecommunication technology
– WANs

Communications at
Present
• Known as Information Communication
– Data, image, audio and video
communications

• A necessary topic for IT professionals
• Focus
– Microcomputers
– Digital communication technology
– LANs, WANs etc.

• Internet
– Internet, Intranet and Extranet

Data and Information
Communication
Data

Computer
Data

Information

Image

Audio

Video

Real-time streaming

Audio and Video
Transmission
• Requirements
– More bandwidth is required
– Real-time transmission may also be
required

• Solution
– Compression
– Streaming

• Note: Streaming includes
compression as well

Comparison of Data and
information Communication

Data and Information
Communications
Data Communications
Alphanumeric data
Mainframe focused
Analog technology
Specialized topic
Private network based
WANs

Information
Communications
Data, image, audio
and video
Microcomputer
focused
Digital technology
General topic
Internet based
LANs and WANs

Key Words






Mainframe
Centralized
Analog
Data
Telecommunicatio
n network







LANs
Distributed
Digital
Information
Computer
network (Internet)

Hosting Services
• Godaddy
• 1&1
• MediaTemple
• Yahoo hosting service

Homework
• Difference between Internet,
Intranet, Extranet
• Explore Godaddy and other hosting
services
• Download, install and experiment
with Microsoft Encoder and Audacity
– Convert between different audio file
formats

End of Module

Module

Opportunities and
Certification

© N. Ganesan, Ph.D. , All rights reserved.

Opportunities in
Communications
• Specialized knowledge is required for
specialist in the communication field
– Example: Network Engineer
– Certification examinations are available for
attesting to the special skills

• Some knowledge of communications is
required of all in the computer field

Certification
• Microsoft Certification
– MCSA & MCSE

• CISCO Certification etc.
• Network+ Certification
• Different vendors offer certifications at
different levels of expertise
– Contact their web sites for further information

Certification Websites
• Microsoft
– http://www.microsoft.com/learning/mcp
/certifications.mspx

• CISCO
– http://www.cisco.com/en/US/learning/l
e3/learning_career_certifications_and
_learning_paths_home.html

Key Words
• Microsoft certifications
– MCS*

• CISCO certification
• Network+

End of Module

Module

Information Communication
Growth Factors

© N. Ganesan, Ph.D. , All rights reserved.

Information
Communications: Growth
Factors

• Internet
• Fast access technologies for the Internet
ramp
• Emergence of microcomputers as a serious
business and home computing tool and the
focus on connectivity
• Move from large mainframe based
infrastructure to LAN based structures
• Client-server computing architectures
• Emerging concept of terminal servers

Growth Factors Continued
• Home networking
• Digitization of telecommunication lines
• Wireless networking
• Multimedia on the Internet
• Internet security
• Virtual Private Network
• Voice over IP (VoIP)

Homework
• Fast access technologies
– DSL, Cable, T1, T3, OC1, OC2
– Home fiber connections

• IBM business computers
– Replacements for mainframes

End of Module

Module

Evolution Physical Network
Architecture

© N. Ganesan, Ph.D. , All rights reserved.

Evolution
• Physical architecture
– From mainframes to LAN based

• Functional architecture
– Centralized mainframe based architecture to
LAN based client-server architecture
– In the case of LAN based architecture, clientserver evolved following the initial
introduction of the peer-to-peer network
architecture
– Client-server architecture is now followed by
terminal server architecture

Early Mainframe-based
Centralized Architecture
External Analog
Lines

Mainframe
MiniComputer

Term.

Front End Processor
Modem
Server
Concentrator
Term.

Term.

Distributed LAN Based
Architecture
LAN
Mainframe/
Minicomputer
Systems

External Digital/
Analog Lines

Fiber Optic Backbone
(FDDI) or Switched Network
Connectivity

Modem
Gateway
LAN

WAN (Internet)
Gateway
(TCP/IP)

Current Trend in
Distributed Architecture
Source:
CISCO

Major Components of the
Distributed Architecture









Clients
Servers
Network interface cards
Cables (copper and fiber)
Switches
Routers
Internet ramps
Internet

Key Words





Mainframe based
Centralized
Distributed
Fiber ring

• Fiber switches

End of Module

Homework
• Explore some of the Catalyst
switches at Cisco

Module

Evolution of the Network
Functional Architecture

© N. Ganesan, Ph.D. , All rights reserved.

Network Architectural
Evolution
• Mainframe
• LAN
– Peer-to-Peer
– Client Server
• File server
• Application server
• Terminal server

Peer-to-Peer Networking
• Initial architecture of the LAN prior
to client-server architecture
• Each client operates on equal
footing in sharing resources
• Unlike the client-server
architecture, there is no server on
the network in peer-to-peer
networking

P2P Sharing
• Basic sharing is supported
– Files
– Printers
– Internet connection

• Large scale sharing of databases
and other business applications
are not included in P2P sharing

Client-Server Evolution
• Client-server architecture is always
identified by the presence of a server
• The evolution of client-server can be
traced to three sub-architectures that
are based on the functional feature of
the server
– File server
– Application server
– Terminal server

Preview of File Server
Computing
Back-end data storage.
Server

Clients

Front-end computing
All the processing of the application is done at the client.

Preview of Application
Server
ack-end data storage and local retrieval
of data.
Computing
Server

Clients
Front-end interface and data manipulation tools.
Application processing is shared between the client and
the server.

A Preview of Terminal
Server Computing
Powerful
Terminal
Server

Extensive back-end data
storage, retrieval and
Processing

Thin Clients

Front end processing limited to terminal operations

Factors Used in the
Comparison of Architectures
• Point of execution of applications
• Network traffic
• Security
• Hardware/Software requirements
• Total Cost of Ownership (TCO)

Path of Evolution
More power to the user
Peer-to Peer
Distributed
Network

Centralized
Mainframe

Terminal
Server

Application
Server

File Server

Reduced cost of ownershipBetter management of shared dat

Homework
• Browse for wiring closet, RJ-45
patch cables, wiring rack, punch
block etc.

End of Module

Module

Digitization of
Telecommunication Lines

© N. Ganesan, Ph.D. , All rights reserved.

Digitization Of Telecom
Network
• Initial telecom network was based on
analog technology
– Copper wire
– Electronic transmission
– Coaxial cables and twisted pair cables

• Current telecom
– Copper wires and fibers
– Electronic and optical transmission
– Fiber cables and twisted pair cables

Digital WAN Carrier
Technologies
• DSL
• ISDN
• T1, T3 etc.
• OC1, OC3 etc.

WAN Communication
Technologies
• FDDI and CDDI
• Frame Relay
• Asynchronous Transfer Mode (ATM)

Voice Transmission
• Past is based on analog technology
• Currently, it is moving to digital
technology
– VoIP

Access Speeds
• Fastest speed of an analog modem is
around 56K bps
• Newer and mostly digital access
technologies such as DSL can operate at
faster speeds
– Download speed is usually in Mbps
– Upload speed is in Kbps

• ADSL and SDSL
– In SDSL both upload and download
speeds are the same

Typical DSL Speed
• Upload
– 128K bps

• Download
– 1.3M bps

Some DSL Providers
• Covad
– http://
www.covad.com/products/access/
dsl.shtml

• SBC
– http://www02.sbc.com/DSL/

• DSL Extreme

Testing the Access Speed
• The current bandwidth of a
connection can be tested by
accessing websites that test the
connection speed
– www.dslreports.com
– www.2wire.com

Access Security
• www.grc.com

Summary of Access
Technologies
for
the
s
s
t
e
c
c
Internet
re Ac
i
DN
D
e
t
Sa

t
lli

e

IS

le
b
Ca

M

m
e
od

xD
SL

End of Module

Module

Internet Architectures

© N. Ganesan, Ph.D. , All rights reserved.

Architectures
• Internet
• Intranet
– An Internet restricted to the
company’s own perimeter

• Extranet
– Intranet extended to include outside
organizations dealing with the
organization

Internet Defined
Internet Backbone
run by major carriers
(TCP/IP etc.)

SOHO
User

Internet
Service
Provider
(ISP)

Internet
Service
Provider
(ISP)

Individuals

Company
Network

Firewall

Internet

Intranet Defined

Internal Company
Backbone
(TCP/IP)

Departmental
LAN

Departmental
Computer
System

Mini or Mainframe
Computer systems

Extranet Defined
Other businesses
dealing with
company A.

Internet

Company’s
Intranet

Business
Associates

Virtual Private Network
(VPN)

A Note on VPN
• Created by tunneling into the
public network
• Tunneling is done largely by
encrypting the computer data

Virtual Private Network
(VPN)

Internet

Fire Wall
Company’s
Intranet

Point-to-Point
Tunneling Protocol
(PPTP)

End of Module

Module

Internet Access

© N. Ganesan, Ph.D. , All rights reserved.

Access
• Analog Access
• Digital Access
• Remote execution
• Telecommuting

Analog Internet Access
Software:
Web Browser
Serial Port
Micro

Gain access to the
resources on the WWW.

Modem

Access provider
ISP

Internet

Digital Internet Access

Software:
Web Browser

Network
Port
Micro

Gain access to the
resources on the WWW.

Access provider
DSL
Modem

ISP

Internet

Computer to Computer
Access
Gain access to a company’s
mainframe to run Unix applications

Micro

Modem

Public
Switched
Network (PSN)

Software: ProComm Plus, Hyper
Terminal, PCAnywhere, Remote
Desktop
Micro

Modem

Telecommuting
Terminal Services
Satellite
Office
PSN
Home
Terminal Services

Terminal Server

Main Office

Telecommuting Options
• Employer supported
– Previous example falls into this category
where the employer provides access to the
office computer from home
– Example: Terminal services

• User initiated
– Gain access to one’s computer in the
office
– A remote control software is required
– Examples: XP Remote Desktop and
GoToMyPC

Some Communication
Software
• Hyper Terminal
• Telnet
• FTP
• Procomm Plus
• Remote Desktop

Homework
• Dlink home network router
• Linksys home network router

Remote Operation
• Gotomypc
• logmein

End of Module

Module

Networks

© N. Ganesan, Ph.D. , All rights reserved.

Computer Networks
• Simple
– A single LAN

• Intermediate
– Departmental

• Enterprise
– Campus LANs and organizational LANs

• Advanced
– WANs such as an Internet based Virtual
Private Networks (VPNs)

Typical Wired LAN
Client OS
Client 1

Switch

Windows
2000/2003,
Linux

Windows XP/Vista; Linux
Client 2

Server:
Network OS,
Applications,
Data etc.

Client 3

Server Operating
System

Typical Wireless LAN
Client OS
Client 1

Windows XP/Vista; Linux
Client 2

Client 3

Wireless NIC

Wireless Access
Point

Server:
Network OS,
Applications,
Data etc.

Windows
2000/2003
Server,
Linux

Some LAN Applications







Share business applications
Share data
Share printers, modems etc.
Share the Internet and Internet resources
Send electronic-mail
Engage in audio/video streaming and
conferencing
• Act as the infrastructure for the .net or J2EE
architecture

End of Module

Module
Network Security

© N. Ganesan, Ph.D. , All rights reserved.

Network Security
• Network security is an important
issue given the fact that many
computers are connected to the
Internet using broadband
connections

General Security Threats
• Viruses
• Denial of service attack
• OS vulnerabilities
• E-mail vulnerabilities
• Macro execution vulnerabilities
• Ect.

General Security Measures
• Anti-virus
• Anti-spyware
• Anti-spam software
• Firewalls
– Both software firewalls and hardware
firewalls can be installed

Secure Communications
• Cryptography
– Encryption

• Virtual Private Network (VPN)
• IPSec and other secure protocols
• Digital signatures

Examples of Protocols for
Secure VPN
• PPTP
• IPSec with encryption
• IPSec with L2TP
• SSL with encryption

Examples of Protocols for
Trusted VPN
• MPLS with constrained distribution
of routing information through BGP
("layer 3 VPNs")
• Transport of layer 2 frames over
MPLS ("layer 2 VPNs")
(Source:
http://www.vpnc.org/vpn-standards.
html
)

Encryption









PKI
RSA ?
MD5 ?
PGP
SSH
HTTPS
DES
AES

End of Module

Module

Wide Area Networks

© N. Ganesan, Ph.D. , All rights reserved.

WAN: The Early Days
• Telecommunication needs
– Centered on analog technology

• Data communication needs
– Centered around digital technology

• Digital to analog interface
– For long distance computer
communications

Long-distance
Communications
Modulation
Interface

Digital

Digital
Analog

Plain Old Telephone Service (POTS)

Initial WANs
• Overcome the limitations of general
purpose analog telephone lines
• Better conditioned lines such as leased
lines were used on the network segment
• Driven by a collection of computers to
route the data traffic from its source to
its destination
• Arpanet was the first WAN that was
created

A Summary of the Basic
Components of the WAN
Routing devices

Leased lines

Computers/
Routing algorithms

Present Status of WANs
• Information is carried in digitized
form
• Digital communication lines
– Over copper wire
– Over fiber-optics

• Digital merger
– Telecommunications
– Computer communications

WANs: Present and Future
• Fully digital
• Technologies
– Frame Relay
– ATM

• Point-to-point digital
communication will become the
norm

Emerging WAN
ATM Switches

ATM operating at several
hundred Mbps
Digital
Ramp
Business
Computer
System

High speed digital lines:
OC3, OC48 etc.

Summary:Possible
Convergent Technology
• Networks





Local
Enterprise
Wide area
Global

ATM

Point-to-point ATM connection may become
possible?

ATM Possibility
Internet Backbone
Client 1

Client 2

1 Gbps

25 Mbps
300 Mbps
Server

100 Mbps

ISP

Likely Scenario
• Ethernet on the desktop
• Possibly, ATM on the backbone

Ethernet Challenge
Client 1

Client 2

10 Gbps
1 Gbps
(Gigabit)

Hub
ISP

10 Mbps/
100 Mbps/
1 Gbps/
Server
10 Gbps

100 Mbps
(Fast)
10 Mbps
1 Mbps
(Past)

Current Ethernet Speeds
• 1G bps used widely
• 10G bps is gradually gaining
grounds
• 100G bps is on the horizon

Net Result
• At the local level (LAN) Ethernet
will remain the technology of
choice for the foreseeable future
• At the WAN level, ATM will
dominate over other WAN
technologies

The Digital Future: Fusion
• Digital fusion
– Computing
– Telecommunications

• Use of computers and the Internet
in all forms of communications that
would include data as well as all
forms of media
– An example is Voice over IP (VoIP)

Possible Scenario
• IP based universal digital
communication over the Internet
with IP addresses as the point of
identification
– Data, voice and video communication
will be done over the Internet

Explore High-speed
Internet
• 10 Gpbs solutions

End of Module

Module
Sample Applications

© N. Ganesan, Ph.D. , All rights reserved.

Some Application Areas
• Networking
– Various server applications such as
database server application,
messaging server application etc.

• Web hosting and E-commerce
• Voice over IP (VoIP)
• Network Security

End of Module

Module
Voice over IP (VoIP):
Effect of Evolution

© N. Ganesan, Ph.D. , All rights reserved.

Voice Over IP (VoIP)
• VoIP is the digital replacement for
the traditional analog phone line
• VoIP is based on the Internet
– It is packet switched as opposed to
the traditional phone service that is
circuit switched

Voice Over IP Growth
• Growth of VoIP is fuelled by the economy
of using the Internet and the technological
advantage of the digital technology
• It signifies the inevitable use of digital
technology and the Internet to carry voice
• VoIP is poised to grow and probably
become the de facto public voice carrier
technology

VoIP Challenges
• Latency inherent to the IPv4
protocol
• Availability of bandwidth

VoIP Remedies
• Newer protocol such as IPv6 is
designed to address latency
• Faster Internet backbones such as
those using Optical Carrier (OC)
lines and ATM transport
technologies are being introduced
to increase the bandwidth of the
communication lines

Long Term Developments
• Indications are that residential
connections in the long term would
evolve into Internet connections
replacing the phone connection

Business and Residential End
Points
• Instead of identifying an end point
in a business or a residence with a
phone number, it is plausible that
the end point could be identified
with a number similar to an IP
address

VoIP Application: Broadband
Phone
• Broadband phone may be touted
as the first real sign of
convergence between computer
and telephone networks
• VoIP application in the form of
broadband phone will also
contribute to the growth of
communication on the Internet

Broadband Phone
• Uses a DSL or cable modem
connection
• Sample vendor
– Vonnage

• Broadband phone is known as an
Internet appliance

Emergence of Internet
Appliances
• Internet appliances are devices that
can be used without explicit
programming
• The software code necessary will be
stored in firmware in the appliances
• Functionalities of the appliances
could well be chosen with the use of
buttons that may resemble the
buttons on a telephone dial pad

Internet Appliances
• A broad range of Internet appliances will
then become available for residential
use with the broadband phone featuring
prominently as perhaps the most used
Internet appliance
• Other Internet appliances may include
Radios, Interactive TV, Evolving Palm
Pilots etc.

End of Module
End of Chapter

END OF MODULE

END OF CHAPTER

Sponsor Documents

Or use your account on DocShare.tips

Hide

Forgot your password?

Or register your new account on DocShare.tips

Hide

Lost your password? Please enter your email address. You will receive a link to create a new password.

Back to log-in

Close