The Evolution of
Telecommunications
Technology and Policy
Objectives
In this chapter, you will learn to:
Describe the growth of telecommunications technology
since the late 19th century
Identify key inventions and their current equivalents in
telephony technology
Explain the impetus for and impact of AT&T’s divestiture Discuss how government has influenced the way in which
consumers obtain telecommunications services
List current policy trends that affect the
Evolution of Telecommunication
Technology
Today’s telecommunication
technologies have evolved from the
earliest smoke signals to almost
Early Signaling and Telegraphy
Semaphore - a type of signaling, in which visual cues represent letters or words.
Morse code - the transmission of a series of short and long pulses (dots and dashes) that represented
characters.
Duplexing - simultaneously transmitting a signal in both directions along the same wire.
Multiplexing - simultaneously transmitting an
Early Signaling and Telegraphy
1856 - Western Union Telegraph Company was founded. 1861 – Over two thousand telegraph offices operated
Infrastructure
Wires criss-crossing cities and states and
terminating in several exchanges or central offices.
Exchange was also known as a switching point because
the device used to open and close a circuit is known as a switch.
Operators would connect the circuits and complete
the call for the subscriber.
Telephone Technology
1878- The first telephone exchange opened in New
Haven, Connecticut.
Telephone Technology
In 1889 Almon Strowger developed the
automatic switch called the step-by-step.
In 1896 he replaced the button-pushing
Telephone Technology
In 1913, N.J. Reynolds, a Western Electric
engineer, developed a better automatic switch,
the
crossbar switch
. It used a grid of horizontal
and vertical bars, with electromagnets at their
ends. The horizontal bars could rotate up and
down to connect to specific vertical bars and thus
complete circuits.
Original version could complete 10 simultaneous
connections.
By the 1970 a single crossbar could connect 35,000
Telephone Technology
In the mid-20
thcentury AT&T integrated
electronics into crossbar switches
1965 – first electronic switching system was
used
Handled up to 65,000 two-way voice circuits.
Until 1970 all telephone switches depended on
Telephone Technology
1976 – New electronic switching device
was put into service.
Time division switching - a transmission
technique in which samples from multiple
incoming lines are digitized, then each
Telephone Technology
Space division switching - manipulating the physical
space between two lines, thereby closing a circuit to connect a call.
Local switching center (often called a local office) - a
place where multiple phone lines from homes and businesses in one geographic area converge and terminate.
Tandem switching center - an exchange where lines
from multiple local offices converge and terminate.
Toll switching center - an exchange where lines from
Wireless Technology
Telegraphs and telephones are examples of
wireline, or wire-bound technology, because
they rely on physically connected wires to
transmit and receive signals.
Wireless technology
- relies on the
Wireless Technology
Examples of wireless technology
Phones
Radios
Televisions
Wireless Technology
1894- Italian physicist Guglielmo Marconi a
method of transmitting electromagnetic signals
through the air.
Wireless Technology
Induction coil is made by winding wire in a either one or multiple
layers around a metal rod to form a coil then applying a charge
Charged wire induces an electromagnetic field that generates
voltage
Marconi connected an induction coil to a telegraph key. Each time
the key was pressed the coil discharged a voltage through the air between to brass surfaces
Metal filings in a glass cylinder became charged and cohered.
The length of time they cohered translated into short and long pulses.
Pulses were relayed to a Morse code printer.
Marconi invention used the same type of signals sent and
Wireless Technology
Vacuum tube - a sealed container made of glass, metal, or ceramic, that contains, in a vacuum, a charged plate that transmits current to a filament.
Audion - patented in 1907by DeForest, is a type of
vacuum tube that contains an additional electrode in the middle of the positive and negative electrodes.
Boosts or amplifies a signal.
First instants of signal amplification and it formed the basis for all subsequent radio and television advances.
1912- Edwin Armstrong improved the Audion. He
Wireless Technology
Continued experimentation resulted in the
invention of Frequency modulation.
Frequency modulation
is technology used in FM
radio and other forms of wireless technology.
In
Frequency modulation
one wave containing
the information to be transmitted (for example, on
a classical FM radio station, a violin concerto) is
combined with another wave, called a carrier
wave, whose frequency is constant.
Frequency is the number of times each second that a
Wireless Technology
The advent of FM radio afforded the best clarity of
all wireless technologies then available.
Walkie-Talkies use frequency modulation
1946- Bell Laboratories connect the first wireless
car phone to the St. Louis network.
1962- Telstar Satellite successfully transmitted
Wireless Technology
Geosynchronous
- means that satellites orbit
the earth at the same rate as the earth turns.
Uplink
- a broadcast from an earth-based
transmitter to an orbiting satellite.
At the satellite, a
transponder
receives the
Early Computing
1822- Charles Babbage “father of computing”
Computing - the automatic manipulation of input based on logical
instructions.
Difference engine - an English mathematics professor, proposed
an automated calculating machine as large as a locomotive and powered by steam.
Herman Hollerith - used his punch card invention to found the
Early Computing
Electronic Numerical Integrator and Computer (ENIAC) - a
multipurpose computer so large that it required its own 30 foot by 50 foot room.
Early Computing
Memory
- in the mid-1940s, a U.S. scientist
named Jon Von Neumann designed a computer
that was capable of retaining logical instructions
for use at any time, even after the computer
had been turned off, then on again.
UNIVAC (Universal Automatic Computer)
-
the first computer designed for business (and
not merely scientific purposes), became
Early Antitrust Measures
In 1877 Bell and two other men formed the Bell Telephone Company. After acquiring dozens of new patents from other companies and
exponentially increasing its value, the Bell Telephone Company became American Bell in 1880.
In 1882, American Bell gained a controlling interest in the Western Electric
Company, and together, they became known as the Bell System.
In 1885, American Telegraph and Telephone (AT&T) was incorporated as
a subsidiary of the Bell System, with the aim of constructing a long
distance telephone network and providing long distance service (to Bell System subscribers only).
By 1899, AT&T bought out American Bell and became the parent
Early Antitrust Measures
Until 1984, AT&T consisted of the following:
AT&T, the parent company and long-distance provider 22 Bell Operating Companies (BOCs), the telephone
companies that provided local service in different regions of the nation
Western Electric, the manufacturing arm of the
company
Bell Telephone Laboratories, the research and
Early Antitrust Measures
Kingsbury Commitment - fearing that the government
might use its antitrust laws against it, AT&T approached the U.S. Department of Justice in 1913 with a proposal for reducing its monopoly.
As a result of the Kingsbury Commitment, AT&T
The Communications Act of 1934
From 1910 to 1934, the Interstate Commerce
Commission (ICC) regulated telegraph and radio
service.
In 1934, Congress passed the Communications Act of
1934, which established the Federal Communications
Commission (FCC), state Public Utilities
Commissions (PUCs), and initial guidelines for the
telephone industry.
The Communications Act of 1934 also put into law the
Challenging the Monopoly
Hush-a-Phone decision
- a Supreme court ruling that
allowed "foreign attachments," or devices that were not
manufactured by AT&T to be affixed to AT&T telephones.
However, the Hush-a-Phone decision did not allow other
companies’ equipment to interconnect with AT&T lines
Carterfone decision was named after a means of
Challenging the Monopoly
The restriction against interconnecting to AT&T’s
telephone network was challenged in 1965 and
eventually lifted in 1968 through the Carterfone decision.
In 1969, a company called Microwave Communications
AT&T Divestiture
The Modified Final Judgment (MFJ) -
accompanied by over 500 pages of instructions
detailing exactly how AT&T should be divided.
The Justice Department’s primary goal for
breaking up AT&T was to spur innovation and
competition in a field that would prove even
AT&T Divestiture
As part of the MFJ, AT&T was forced to divide.
From the 22 former Bell Operating Companies that provided local
phone service and phone directories, the MFJ created seven Regional Bell Operating Companies (RBOCs).
The business that AT&T kept was separated into two divisions:
AT&T Technologies, which handled the innovation and production
of new technologies, and AT&T Communications, which handled
long distance phone service.
The research and development business, formerly Bell
AT&T Divestiture
Until the divestiture of AT&T, the distinction between local
service and long distance service was not clear.
In the MFJ, Judge Harold Greene subdivided each RBOC
region into Local Access and Transport Areas (LATAs),
roughly equivalent to area codes at that time.
Phone service within a specific LATA was known as intraLATA service.
Companies that supply local, or intraLATA telephone service are
AT&T Divestiture
InterLATA - a service that allowed for calls between
LATAs was known.
Interexchange carriers (IXCs) - another name for
InterLATA service providers. Examples of IXCs include Sprint, MCI (now WorldCom), and AT&T.
Equal access - requiring local phone companies to
The Telecommunications Act of
1996
The Act codified requirements for the interconnection of all local exchange carriers. These policies included:
Interconnecting with other service providers and not imposing any
barriers to interconnection
Enabling nondiscriminatory resale of their services to competitors
Providing number portability, or the ability of telecommunications
service users to retain their same telephone number without hampering the quality, reliability, or convenience of their phone service
The Telecommunications Act of
1996
To increase competition in local phone service, the Act placed the following requirements on all ILECs:
Negotiating interconnection agreements in good faith
Providing competitors with the same type and quality of
access to their facilities that they themselves could obtain at their cost
Providing competitors with access to subscriber information,
such as telephone numbers and billing data
Offering nondiscriminatory, wholesale prices for
Emerging Technologies
At this time, Congress is debating a bill that would
remove all long-distance and high-speed Internet access service restrictions on RBOCs.
One issue that the RBOCs continue to battle is the
access fees applied to each connection with a customer or another carrier.
Lawmakers argue everyone should share the burden
through some type of tax whether on service or equipment.
In 1999, Congress mandated cable service providers to
Emerging Technologies
Digital Divide difference between the haves and
the have-nots. Those who have access to the
“information superhighway” and at what cost.
Recent Bills in Congress
Enhancing rural internet access
Efficient allocation of phone numbers
Methods for ensuring privacy in wireless technology Measure to guard against excessive consolidation of
Summary
In 1837, Samuel Morse invented the telegraph, which consisted
of an electromagnet and a hand-operated switch, known as a key, to alternately open or close an electrical circuit over a wire. What he transmitted was a series of short and long pulses (dots and dashes) that represented characters, known as Morse
code.
To connect multiple subscribers, Alexander Graham Bell
devised the telephone exchange, where subscriber lines
terminated and operators connected the circuits to complete a call.
The first computer designed for business (and not merely
