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Chapter 2

CMNS 253W Chapter Notes - Chapter 2: Samuel Morse, Teleprinter, Punched Tape

Course Code
Frederik Lesage

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Chapter 2 - The History of New Media
The Telegraph
New media dierent from old media in many ways, however some aspects of
old media set pattern for things to come
Challenge of old forms of communication - to send a message any farther
than you can see, you'd have to send a physical object to carry the message
1800s - attention to potential for wires to send messages
Samuel Morse - credited for bringing the telegraph into popular use (may not
have invented it)
oCredited for the coding system - Morse Code - dots and dashes
oIdea of using a digital coding scheme to break a message down into
smaller fragments was revolutionary
oCan be seen as something that led to the contemporary binary system
used by computers now, with dots as Os and dashes as Is
oEstablished an approach to digitization of information that has
persisted into the present day
Telegraph encoding +rst done manually, then later automated by teletype
oProvided a relatively immediate level of connectivity
oFirst transatlantic telegraph took many attempts
oTelegraphs pioneered input devices, storage devices, and underlying
technological methods such as "multiplexing"
Multiplexing - sending more than one message at a time to
make the most of the limited amount of capacity available on wires
oTelegraph companies grew into large monopolies which were regulated
Scanning - a method of breaking a picture or series of pictures into discrete
elements for encoding and transmission to a remote location. This was
pioneered with the telegraph and was repurposed for fax machines, television,
and again for computers
System of "punching" used to send messages - telegraph operators would
use a small device to punch holes in a paper tape to represent the code, and
would run the tapes through another machine that read the holes and
generated Morse code.
oAllowed company to send telegram later when system was less busy
oSame could be done on receiving end - messages could be printed and
distributed later on
oBecause of this ability to store and forward messages, pricing options
could be done based on how quickly a message needed to be delivered
oModern computer networks carry the same storage and forwarding
Metcalfe's Law - observation rather than law of nature - Metcalfe predicted
that the value of a network lay in the number of possible connections between
the members - or nodes - of a network
oIncreasing value of a network based on how many connections it has
oMathematically can be represented as O(n2) - O is the value, n is the
number of connections
oExplains why people end up getting a telephone or signing up for
email, because value of network grows as more and more people join, and
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