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Overview
Chapter 22 VoIP and Convergence
What is VoIP? VoIP challenges Convergence initiatives
Putting it all together! The Future of Information Technology
Future of the Telephone System?
Co-existing communications systems: The telephone system Cellular Cable The Internet Satellite
Why can’t one system handle voice, video, and data? “Convergence” technologies address the migration of
different information technologies onto a single integrated, ubiquitous network. Wouldn’t this be more economical?
A major telecommunications technology transition involves the growing technical capability of
merging many different information technologies onto a single network: Voice, Data, Video
Telephone (voice) and computer (data) equipment have so much in common that both can share same equipment /network
Web interaction will include phone conversations
What is “The Convergence”?
Voice over Internet Protocol (VoIP) and Convergence
A substantial number of Internet users today use the telephone to connect to an ISP
Prediction: within a decade almost all telephone calls will be made through a direct, high speed internet connection to an ISP using VoIP technology
VoIP
VoIP is one implementation of convergence. Voice conversations (audio information) carried
over the Internet along with other Internet traffic. Why do this?
How much are you charged to make a long distance call? How much are you charged to view a website in
Germany? As long as willing to suffer a less than optimal QoS.
Software only VoIP, E.g., Skype
QoS = Quality of Service
Skype
7 Myths of VoIP By Steven Cherry
http://www.spectrum.ieee.org/WEBONLY/publicfeature/mar05/0305vip.html
VoIP Is Free
The Only Difference Between VoIP And Regular Telephony Is The Price.
Quality Of Service Isn't An Issue Nowadays, Because There's Plenty Of Bandwidth In The Network.
VoIP Can't Replace Regular Telephony, Because It Still Can't Guarantee Quality Of Service.
VoIP Is Just Another Data Application.
VoIP Isn't Secure.
A Phone Is A Phone Is A Phone.
VoIP Challenges The differences between Voice and Data traffic
present several challenges for implementing VoIP. Several hurdles need to be overcome to make
convergence a reality. new protocols and infrastructure, software, faster routers, etc.
VOICE TRAFFIC DATA TRAFFIC
Continuous Synchronous Constant Bandwidth
Bursty Asynchronous Varying Bandwidth
Circuit Switching Packet Switching
Packet switching makes the Internet possible
Conventional telephone systems are based on circuit switching
Problems are likely to arise in transporting voice signals over the Internet using a data communication protocol, such as: Delay Packet loss Variable data rate
Delay While traditional circuit switching of voice has some
delay, IP routing involves much more data handling and therefore more delay. Delay above a certain threshold becomes a cause for impaired communications
Packet loss Packet loss due to temporarily overloaded routers and
insufficient cable capacities is not all unusual in the operation of the Internet. TCP arranges for the retransmission of missing packets. However, if this data arrives too late, then a correct voice waveform may not be reconstructed
Variable data rate If the transmission rate slows down enough, again it
won’t be available for reconstruction of the voice waveform.
More than just cheap long distance calls Upgraded Internet makes this more
feasible Cheap, high-bandwidth Internet connections High-speed computer/network equipment and
protocols Specially designed VoIP routers
The Convergence offers the promise of huge cost savings, and “Bandwidth on Demand” For who?
What’s Driving the Convergence?
Voice/Web e-commerce frontier demands it Voice/Web integrated services Nacent Video phones?
What’s Driving the Convergence?
Other Convergence Initiatives Increasing bandwidth to the consumer
Ethernet in the First Mile Fiber to the Curb
refers to the installation and use of optical fiber cable directly to the curbs near homes or any business environment as a replacement for "plain old telephone service" (POTS).
Fiber to the Home Promoters of fiber to the home want to deliver voice
(up to six lines), data, and television services over a single cable.
now getting more attention because of reduced equipment costs and a bigger demand for service.
Other Convergence Initiatives
Cable companies poised to provide telephone service (Digital Cable)
Phone companies buying cable companies WebTV
Chapters covered
Chapter 1, 2, 3, (4), 5, 7, 8, 9, 10, 11, 12, 13, 15, 16,
Ch 18, 19, 20, Ch (21), 22
Putting it all together!
I’m just surfing on
the net!
Hey Susan, what are you
doing?!
Base station
EM waves
Multiplexing
Satellite
GSM
Radio spectrum
Cellular telephony
Digital telephony
Switching center
A/D conversionNyquist sampling
bandwidth
OS, machine language, CPU
Packet switching
MAC addressFDDI
Token based accessLAN
Fiber optics
router
TCP/IP, DNS
Internet
Attenuation
gateway
http, htmlURL
NIC
Error correction coding
GUI, pixels, digital images, ASCII,
compression
GEO
Central office
Switching center UTP
Repeater
Circuit switching quantization
Bits,bytes
WAN
hackers
firewall
PSTN
Convergence
IP addressing
Did we cover everything?
• No! IT 101 barely scratches the surface
• Gained an understanding of the evolution of information technology and its role in modern society
• Were exposed to fundamental concepts and components of IT, such as computer architecture, networking, and telecommunications
• Introduced to some quantitative aspects of IT
What Are The Social Implications?
Now that you have an understanding of the evolution of information technology and its role in modern society, and the some of its fundamental concepts and components, such as computer architecture, networking, and telecommunications.
What can you do with this knowledge?
Social Web / Semantic Web According to Tim Berners-Lee, the inventor of the Web,
the creation of the internet was not a technical invention but a social invention that has yet to realize its full potential in this regard.
He emphasizes the importance of Web as a medium for social interaction; the real paradigm shift was in enabling collaboration.
Since the Webs’ inception, phenomenal widespread, altruistic sharing of knowledge and resources.
People developed web sites on specialized content and found ways for geographically distant groups to communicate and collaborate.
Sites developed for the sole purpose of collecting and sharing specialized knowledge and resources
act as nodes, portals, or hubs to the WWW system.
Original Concept for the Web “The WWW was designed originally as an
interactive world of shared information through which people could communicate with each other and with machines.”
“I had (and still have) a dream that the web could be less of a television channel and more of an interactive sea of shared knowledge.”
Tim Berners-Lee,founding father of the WWW
Original Concept for the Web (cont)
World wide conversation Peer-to-peer Started out as Peer-to-peer - i.e.
Usenet and DNS Evolved to client/server
Internet Computing Paradigms
Client/Server Transmission model Didactic / Inductive Hierarchical Exploratory Individual Not natural
May not be the best answer for educational solutions
*Peer-to-Peer (P2P) Self-organizing /
Generative Social-Collaborative Decentralization Discovery Consumers are also
producers Natural – spontaneous
*More philosophical - Computing connecting the “edges”
A critical mass of millions of socially-oriented Internet users, leads to:
VoIP Web Services Grid computing Social Networking
Grid computing solves problems by harnessing the CPU processing power of clusters of other computers.
Social computing does the same thing with humans. It solves the problems by getting more people/brain power to work on the problems.
Grid Computing and Social Computing
The Future
2014 Epic Journeyhttp://epic.chalksidewalk.com/
Going Home: http://smartpei.typepad.com/robert_patersons_weblog/2005/02/going_home_our_.html
2029: When computers exceed human intelligencehttp://www.penguinputnam.com/static/packages/us/kurzweil/excerpts/exmain.htm