INFS 370 Telecommunications

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INFS 370 Telecommunications

• Professor Morgan M. Shepherd

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Agenda

• Roll
• Syllabus
• What you should expect

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Roll
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www.uccs.edu/mshepher/infs370

• Syllabus and lecture notes are posted
• Now for your input

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Text

• Business Data Communications and Networking
• GitzGerald/Dennis
• Eighth edition
• ISBN 0-471-34807-4

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If you had one wish...
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Good health

Fame
Long life
Popularity
Good looks
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Dont want to be a schmuck!
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What do people fear most?
Exam
Two trains are heading towards each other. One
starts from NY,
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Speaking in Public
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This will be a GREAT course if...
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We will learn

• Telecommunication jargon
• Telecommunication models
• How to solve typical telecommunication problems
• About telecommunication management issues
• How networks work

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9 to 5 in telecommunications

• What goes into your definition of a dream job?

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Definitions

• Telecommunications
• The electronic transmission of information
• Transmission
• The movement of signals along a communications
  link

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Broken down into its simplest form,
telecommunications is just the movement of bits
from point A to point B.
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We need to understand how that occurs, and how to
manage the people and equipment involved.
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Types of networks

• Differentiated by geographical coverage
• LAN (Local Area Network)
• Covers a few kilometers
• MAN (Metropolitan Area Network)
• Covers a few dozen kilometers
• WAN (Wide Area Network)
• World-wide coverage

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How do we represent information?
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How do we represent information?

• The computer handles this for us.

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What is a byte?
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How many bits are in a byte?
6 ?
2 ?
3 ?
4 ?
5 ?
8 ?
1 ?
7 ?
16 ?
12 ?
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How many bits are in a byte?
6 ?
2 ?
3 ?
8
4 ?
5 ?
7
1 ?
16 ?
12 ?
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Why?
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How many choices can you make with a quarter?
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Two choices

• H
• T

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How many choices can you make with two quarters?
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Four

• H H
• H T
• T H
• T T

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How many choices can you make with three quarters?
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Eight

• H H H
• H H T
• H T H
• H T T
• T H H
• T H T
• T T H
• T T T

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So if I had an 8 letter alphabet....

• H H H a
• H H T b
• H T H c
• H T T d
• T H H e
• T H T f
• T T H g
• T T T h

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But computers only understand 1s and 0s

• 0 0 0 a
• 0 0 1 b
• 0 1 0 c
• 0 1 1 d
• 1 0 0 e
• 1 0 1 f
• 1 1 0 g
• 1 1 1 h

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How many bits do we need to represent...

• The alphabet?

a,b,c,d,e...
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How many bits do we need to represent...

• The alphabet?
• Including the capital letters?

a,b,c,d,e... A,B,C,D,E...
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How many bits do we need to represent...

• The alphabet?
• Including the capital letters?
• And the digits 0-9?

a,b,c,d,e... A,B,C,D,E... 0,1,2,3,4...
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How many bits do we need to represent...

• The alphabet?
• Including the capital letters?
• And the digits 0-9?
• And all the funny characters?

a,b,c,d,e... A,B,C,D,E... 0,1,2,3,4...
_at_,,,!,?...
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Bits

• Small letters 26
• Capital letters 26
• Digits 0-9 10
• Funny characters 100
• Total 162
• So 2? 162?

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2 n

• 21 2
• 22 4
• 23 8
• .
• .
• 27 128
• 28 256

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Eight bits covers us

• By using eight bits to represent each character
  we can uniquely identify each character

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Examples
a 01100001 b 01100010 c 01100011 A
01000001 B 01000010 C 01000011
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The network
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Whats in the cloud?
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Whats in the cloud?

• A bunch of computers
• All operating like old time switchboard operators
• These computers are primarily responsible for
  routing all the traffic

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How does a phone call work?
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Why do we care how this routing occurs?
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Why do we care how this routing occurs?

• The more hops our route takes, the longer it
  may take for the data to arrive

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Some simple network commands

• Ping
• Used to see if the computer at the other end is
  there, or awake
• Tracert
• Used to see all the computers we have to go
  through before our data makes it to the
  destination
• Returns the Internet Control Message Protocol
  (ICMP) messages

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Network exercise

• Go to Start
• Then Run
• Or just hit the windows key R
• Then type cmd

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Using the ping command

• Ping the brain machine from the lab
• ping brain
• ping brain.uccs.edu
• Ping the Colorado Springs web site
• ping www.coloradosprings.com
• Ping the Google site
• ping www.google.com

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Using the trace command

• Trace the Colorado Springs web site
• tracert www.coloradosprings.com
• Trace the Google site
• tracert www.google.com
• Which had more hops?

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Your biggest task in this field

• Keeping the users happy, vs. keeping management
  happy

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Managers wants
Users wants
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Managers wants
Users wants
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Throughput vs. response time
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Throughput

• The amount of data you can push through in a
  given amount of time
• The more data you push through (transmit), the
  greater the throughput

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Response time

• The amount of time you have to wait before the
  system does what you asked it to do.
• Usually thought of as How long after I hit the
  enter key do I have to wait for a new screen?

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A brief history

• Started in the 1950s....

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Milestones in telecommunications

• 1897
• Braun invents the CRT

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Do we need to know this stuff !?!
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Milestones in telecommunications

• 1897
• Braun invents the CRT
• WWI
• Teletype is invented

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Milestones in telecommunications

• 1897
• Braun invents the CRT
• WWI
• Teletype is invented
• WWII
• Van Duuren invents ARQ transmission

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Milestones in telecommunications

• 1897
• Braun invents the CRT
• WWI
• Teletype is invented
• WWII
• Van Duuren invents ARQ transmission
• Early 1950s
• MIT ties 23 networks together

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Milestones in telecommunications

• 1960
• Maiman invents the laser

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Milestones in telecommunications

• 1960
• Maiman invents the laser
• Early 1960s
• Bell Labs invents digital phone switch

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Milestones in telecommunications

• 1960
• Maiman invents the laser
• Early 1960s
• Bell Labs invents digital phone switch
• 1961
• Corbato invents time sharing computer

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Milestones in telecommunications

• 1960
• Maiman invents the laser
• Early 1960s
• Bell Labs invents digital phone switch
• 1961
• Corbato invents time sharing computer
• 1962
• Bell Labs invents the T-1

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Milestones in telecommunications

• 1963
• Rosen invents geosynchronous satellite

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Milestones in telecommunications

• 1963
• Rosen invents geosynchronous satellite
• 1965
• Lucky makes auto equalization techniques

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Milestones in telecommunications

• 1963
• Rosen invents geosynchronous satellite
• 1965
• Lucky makes auto equalization techniques
• 1960-1969
• RS-232 standard evolves

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Milestones in telecommunications

• 1963
• Rosen invents geosynchronous satellite
• 1965
• Lucky makes auto equalization techniques
• 1960-1969
• RS-232 standard evolves
• 1968
• Carterphone FCC ruling

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Milestones in telecommunications

• 1970
• Aloha network developed

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Milestones in telecommunications

• 1970
• Aloha network developed
• Early 1970s
• Corning develops fiber optic cable

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Milestones in telecommunications

• 1970
• Aloha network developed
• Early 1970s
• Corning develops fiber optic cable
• 1971
• ARPANET was formed

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Milestones in telecommunications

• 1970
• Aloha network developed
• Early 1970s
• Corning develops fiber optic cable
• 1971
• ARPANET was formed
• 1974
• DEC develops Ethernet

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Milestones in telecommunications

• 1983
• OSI develops the 7 layer ISO model

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Milestones in telecommunications

• 1983
• OSI develops the 7 layer ISO model
• 1984
• ISDN networks are developed

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Milestones in telecommunications

• 1983
• OSI develops the 7 layer ISO model
• 1984
• ISDN networks are developed
• ENOUGH WITH THE HISTORY ALREADY!!!!

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Next week

• Skim through the entire book
• If you havent already
• Not as if youll be tested, but just to get an
  idea about what is in store
• Read chapter 1
• As if you will be tested