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Objective: In order to understand the social implication of the advances in communication, it is first necessary to study the technical aspect of communications. Then we shall examine the issue of substitution of communication for travel in such social innovations as teleconferencing and telecommuting. The index for this section is:
The electromagnetic spectrum is currently used for many types of
analog and digital communication. Electromagnetic waves include
radio, micro, light, infrared, x rays, and gamma rays as shown
below:
These waves have the following characteristic in a vacuum: C = f w In this equation, C is the velocity of light; f is the frequency; and w is the wave length. The communication capacity of an electromagnetic wave is twice its frequency, and over the electromagnetic spectrum the frequency varies by a factor of 10 raised to the 15th power. [ This number is a million times a million times a thousand.] THIS MEANS THAT THE POTENTIAL CHANNEL CAPACITY OR THE POTENTIAL VOLUME OF MESSAGES VARIES BY THE SAME FACTOR OF 10 TO THE 15TH. The allocation of the spectrum between gadgets( including cordless phones, baby monitors and garage-door openers), CB radio, radio ( AM, FM and shortwave), television, cellular phone, and satellite communications is an economic/political problem controlled in the US by the FCC. As new types of communications devices are developed, turf battles occur over the use of the electromagnetic spectrum. The FCC has auctioned off portions of the electromagnetic spectrum.
Electromagnetic Spectrum:
Currently the three main types of wired communication are the telephone, cable TV, and computer networks.
Unlike computation, communication made tremendous advances before
the advent of the integrated circuit. Communication engineers
developed the analog telephone that transmits the waveform of human
voice into a worldwide system displacing the telegraph. The evolution
of the phone system has been driven by providing humans the type of
service they desire. Humans want their conversations over phones to
be a close approximation of live conversations between two people.
Consequently, phone conversations require a continuously open
channel, and people want their messages to be transmitted as quickly
as they are when the two individuals are standing near each
other.
Also, as most individuals use their phones at infrequent intervals, the
phone system has been designed on the premise that most phones will be
idle at any one instance. This fact enables the phone companies to
connect phones through exchanges (switches). If the phone companies had
simply hardwired every phone to every other phone, the number of
connections would have increased as the square of the number of phones.
Just imagine the number of wires there would be entering your home or
apartment. Your phone only requires a single line to the switch where
it is connected to other phones as requested by dialing.
The system is designed with a tradeoff between the number of switches
and the number of calls which can be processed at one time. For
example, if you have 100 telephones and you hook each one with every
other phone, you would need 10,000 connections. If you create a
switch with 10 input and 10 output lines, ten telephone conversations
are possible at one time between any 10 pairs of phones. If the
switch has 20 input and output lines, 20 pairs of phones can be
linked at any one time. To design systems which meet the estimated
demand for phone conversations almost all the time, telephone
analysts developed a branch of operations research called queuing
theory.
To initiate a phone conversation, the two parties must be connected
in a phone channel through the switch, which remains continuously
open until disconnected by one of the parties. At first, phone calls
were manually placed by human telephone operators manning the first
type of telephone exchanges (switches). Later, communication
engineers developed automatic switchboards which could connect phones
by dialing. The reason for developing switches is a simple matter of
economics in that creating automatic switches to replace manual
switches greatly reduces the need for labor to operate the phone
system.
Currently, the telephone system is in the process of switching from
analog to digital. The switch to digital communications is promoted
by the advances in microelectronics. These advances in integrated
circuit technology can be used to build ever cheaper and more
powerful communication devices. For example, today telephone
switchboards are simply special purpose computers with software to
provide services such as call waiting. Also, with digital
communications, errors in communication can be more easily controlled
than with analog communication. The telephone system is currently a
mix between analog and digital technologies. Currently, long distance
is generally digital, while local service is analog.
Among switches, either within a city or between cities, it is not
efficient to string a separate phone line for each phone
conversation. Instead, phone conversations are multiplexed,
that is combined, so that many phone conversations can be carried in
a single higher frequency of the electromagnetic spectrum. Over time,
the demand for communication capacity for phone traffic, data
communications, and now image communication, such as pictures and now
video teleconferencing, has constantly increased. Consequently,
communication engineers have moved to harness higher and higher
frequencies in the electromagnetic spectrum.
The latest is laser light in optical fibers, which represents a
1,000,000 increase in capacity of over microwave communications.
Because these optical fibers can fit in existing copper cable ducts,
they have a much greater capacity than the copper, and they are no
more expensive than copper, their use is expanding very rapidly.
Through the utilization of railroad rightaways, several optical fiber
networks have been constructed to connect the various major
communication centers.
A laser light-optical fiber communication system consists of encoding
and decoding devices, a transmitter, silica fibers, repeaters, and a
receiver. Through applied research the capacity of such systems is
increasing 10 fold every four years, and by 1992 it was possible to
transmit 100,000 billion bits of information 10 kilometers per
second. A basic problem in any communication system is attenuation,
which is the disintegration of the signal as it travels down the
communication channel. To restore the signal to its original
strength, amplifiers (repeaters) must be placed at regular intervals
in the system. The increase in capacity has been obtained by (1)
increasing the purity of the optical fiber, (2) developing optical
repeaters, (3) developing better laser generators, and (4)
experimenting with various pure and mixed frequencies of laser light.
For example, an optical repeater is created by doping the optical
fiber with the rare earth element erbium. This is a major advance
over previous repeaters which necessitated converting the light beam
from light to electricity, amplifying the electrical signal, and then
converting the electrical signal back to light.
Finally, the phone systems have had to develop elaborate billing
systems to charge individual customers for each long distance
call.
Telephone
Cable TV is currently a high capacity analog signal. Since each station needs a frequency of 6M, 50 cable channels are multiplexed into a signal of 300M hertz. Cable systems frequently use optical fiber to junction boxes and then use coaxial cables into residences. These coaxial cables have a much higher capacity than the twisted copper wire phone system, but currently cable systems are one-way broadcast communication systems. There are a few experimental interactive systems with a limited amount of interaction. Because cable systems broadcast a fixed set of channels into each home, they have no need for exchanges found in telephone systems. Also, because each household has a fixed number of channels, cable companies do not need an elaborate billing system as that for long distance telephone traffic.
Cable TV
Communication networks for computer communication generally connect
office machines or factory machines. LANs are now everywhere in
corporations and public institutions. Such networks usually do not have
switches like phone networks. A common type is a loop in which messages
from the sender travel until they reach the receiver station. The loop
is analogous to a party line of telephone. But, as the number of
stations on the loop increases, the amount of traffic can greatly slow
down communication. For this reason in larger organizations, networks
are subdivided into smaller networks connected by bridges, which
connect LANs with the same protocols, and routers, which connect LANs
with different protocols. For example, the UT economics department has
its own LAN which is connected to the larger UT collection of networks
for the various departments and colleges.
Digital data and text communication between machines generally does
not require a continuous open channel because the recipient usually
will tolerate a time delay between the time the message is sent and
the time the message is received. Consequently, such communication
can be broken down into standard sized packets which can be sent
individually from sender to receiver. One advantage of packet
communication is that it provides a mechanism to correct errors, or
if this can not be accomplished, resend the packet until it is
communicated without error. One of the first data protocols was x.25,
which is very robust in noisy channels. With less noisy channels, the
protocol, Frame Relay sends data more quickly because it spends less
time checking for errors.
Packet communication in computer networks is very different from
continuous voice or video communication, which as was pointed out,
requires a continuous open line. In contrast, each packet can travel
a different route through the communication network. For example, on
the internet some packets can travel from New York to Los Angeles
through Chicago and some through New Orleans. When they arrive, all
the packets can be assembled into the original message. With a voice
or video phone, you either have the capacity to transmit the message
in real time or you don't. With a continuously open channel there is
no noticeable time delay on the earth. With data packets, the higher
the capacity the more quickly the packets can be sent through the
system. This is why downloading pictures on Netscape is much faster
at UT than at home with a modem. The capacity at UT is at least five
times most modems.
Data traffic for long distance is sent over many types of networks. For example, telephone networks and private computer networks carry great volumes of data traffic. Currently the computer network that connects almost all computer networks is known as the Internet In 1964 the RAND Corporation issued a report calling for a military network that had no central authority that would survive a nuclear attack. The Defense Department Advanced Research Projects Agency set up the ARPANET in 1969. This network supported researchers associated with military research. In 1986 the National Science Foundation, NSF, created the NSFNET connected to ARPANET to connect supercomputer centers to research universities. This network gradually connected most higher education centers. There was a great expansion in traffic as the combined network was used for all types of research. The third phase in the growth of the Internet started in the 1990s when ARPANET and NSFNET were replaced by six commercial networks. The current rapid expansion in Internet usage is due to exploding commercial applications and general use. How fast is the Internet growing? If it keeps growing at the same pace everyone on the planet will be a user by 2003.
The protocols behind the Internet are the TCP/IP protocols. TCP covers
the packets and IP covers the addresses. In 1991 the adoption of OSI,
open systems interconnection made it possible to connect almost any
type of computer network to the Internet even if the connecting network
was not based on TCP/IP. What this means is that almost all computer
networks can and have been connected to the Internet
The growth of the Internet is associated with the type of services that can be provided through the Internet Tom Truscott and Jim Ellis, two graduate students at Duke created USENET in 1979 based on the Unix UUCP program. USENET has a very large number of discussion groups on practically any topic imaginable. USENET was a separate network from ARPANET. In 1972 Ray Tomlinson created the first E-mail program. At first E-mail users were generally researchers communicating with other researchers. Currently most people who use computers use E-mail. As all of you are well aware, E-mail is free, fast and generally more effective than playing voice tag.
At first there were numerous unconnected E-mail systems in
information utilities such as CompuServe, Prodigy and Internet. The
use of E-mail is exploding in the 1990s because of the adoption of
the world standard, x.400 and the creation of E-mail directories
under the x.500 standard. The adoption of these standards and OSI
means interinstitution E-mail communication has become as easy as
intrainstitution E-mail.
In 1991 WAIS and Gopher were created. The service that led to the explosive growth of the Internet was the creation of the WWW, generally called the WEB, by CERN in 1992 and the creation of the first WWW browser MOSAIC in 1993. WWW browsers, now almost always Netscape or Explorer, reduce the knowledge requirement to use the Internet to basic computer literacy in point and click operations. In addition, browsers folded services such as USENET and E-mail in the WWW browser as additional options. Thus using Netscape or Explorer the user has access to all Internet type services in an easy to use form.
The fact that browsers cover all the Internet services in an easy to use form is just one aspect of the explosion in Internet use. The other is that browsers are created such that some variation of the browser runs on all types of operating systems whether Unix, Window, or MacOS. This means that WWW applications are independent of the machine or operation system. A firm can use the WEB to create firmwide applications regardless of the fact that the divisions of the firm might have very different computer equipment and operating systems.
These two factors mean that more and more different types of activities will go through the WEB. Also, the capabilities of the WEB will keep on expanding to include voice and video. The current HTML is scheduled to be augmented by a more general XML next year. Over time XML may displace HTML.
Internet traffic is growing by a factor of about 4 each year; whereas phone traffic is growing about 10% each year. To accommodate this growth communication firms have strong economic incentives to make the maximum use out of optical fiber networks. The current trend is dense wavelength division multiplex (DWDM). This buzz word means sending many optical wavelengths down an optical fiber at one time. The equipment cost to do this is only 40% the cost of laying a new fiber. In 1999 the state of the art is 80-120 wavelengths each carrying 10 gigabits of data. Because of interference there is a limit to how many wavelengths. My guess is that the more wavelengths the closer you have to have the repeaters (amplifiers) so the cost goes up.
Research and development is focused on creating optical equipment to avoid communication systems that convert light to electricity and then back to light. DWDMers can handle putting a light wavelength on the communication system and taking one off without having to convert from light to electricity and then back to light. In the future researches may develop optical switches that can route traffic optically the way electrical switches currently do.
An active area of technological development is merging the telephone and computer. This is useful, for example, for sales persons who when they get a call from a customer, can immediately bring up all pertinent information on their computer. The latest is the expansion of telephone conversations over the Internet using VOIP, a standard for IP phone.
Computer Communications
Wireless radio was invented by Marconi at the turn of the century. In the twenties the AM radio broadcast industry was created. Later the higher quality FM radio was introduced. Interactive radio communication is used by ships, airplanes, remote stations, and ham operators. The commercial broadcast TV industry was created after World War II. These industries are all allocated portions of the electromagnetic spectrum for their activities. By 2010 TV will shift to high definition digital.
Radio and Television
22,000 mile orbits: By placing a satellite in an orbit with a radius of 22,000 miles, the satellite goes around the earth once a day. If the orbit is about the equator the satellite appears to be stationary with respect to the earth. To minimize interference you must keep these satellites separate (no more than 90 in this orbit). Such satellites are used for broadcast TV and multiplexed phone conversations. Communication from earth to satellite uses microwave communications, which travels through clouds. Low-orbit satellites can also be used for communications systems; however, such a system is much more complicated because the antennas must follow a moving target and shift between satellites as they go over the horizon. Satellites make excellent communication relay stations because you do not need any ground network. Corporations establishing private communication systems outside the telephone system are big users of satellite communications. Third world countries such as India also make extensive use of satellite communications because it is much cheaper to reach the millions of villages by satellite than try to string copper or fiber cable. The emerging communication system will be a mixture of optical fibers between major nodes and of satellite communications in rural areas.
GPS: The orbits for the global positioning system are 12,000 miles. To accurately determine the position of an object on the earth requires triangulation from three satellites. The system was created for the military, but gradually the number of civilian uses has grown and grown. For example, truck companies can know the exact position of all their vehicles and hikers can know exactly where they are. Europe is puting up its own system to compete with the US.
Low Earth Orbits: The disadvantage of satellites at 22,000 miles for voice and video communication is that there is a 1/2 second delay in the communication of the messages because of the distances involved. Motorola has created a low earth satellite system, Iridium with 77 satellites (Iridium has 77 electrons; however, the number of satellites has been reduced to 66) which will eliminate the 1/2 second time delay. The cost of service was to high and Iridium went bankrupt. But, quess what? Because the Iridium system is an excelent miltitary communication device for ships and sea and soldiers in places like Afganistan, the military is now supporting Iridium. [The Iridium system was the only system that worked at ground zero on 11 Sep 01.] They use encrypted transmissions. It may be that this system will slowly gain a commerical market for out of the way places and emergencies when ground communications fail such as hurricanes.
Satellite Communications
- Radio:
- Television
- Telephone: Iridium
- GPS tutorial
- 22,000 miles around equator
There are two types of wireless communication networks-voice and data. As is the case with wired networks, voice has a continuously open circuit when calling, and data sends packets without a continuously open cirucuit.
There are three approaches to transmitting wireless messages-- (1)FDMA that assignes each phone a different frequency. This approach is used for analog voice wireless; (2) TDMA splits each freqency into time slots. This is three times as efficient for digital voice; (3) CDMA provides each phone a unique code to filter the message spread over the entire frequency domain. This approach is more efficient than TDMA. In order to minimize interference and send as many messages as possible wireless networks are organized into low power cells such that the same frequencies can be used by nonadjacent cells. If everyone owning a wireless phone would try to call at the same time the system would be completely overloaded.
In voice and data wireless networks there are competing standards. For voice, Europe, Africa, and much of Asia uses GSM, a TDMA standard which the US uses a variety of analog and digital standards. These standards are evolving. The first standards, 1G were analog with varying voice quality. The second generation, 2G, were digital in the range of 9.6-14.4kbps and exanded the number of users and offered more services such as e-mail and the internet The 3G raises the communication rate to 2Mbps in buildings, 384kbps in urban areas and 144kbps in wide area networks. This is enough bandwidth to offer multimedia services such as streaming video internet. An interum standard 2.5G with a transmission rate up to 153Kbps was proposed. We are in the process worldwide of moving to the 3G standard.
Likewise data wireless networks have evolved. Earlier standards were the ARDIS, RAM Mobile Data and CDPD standards. ARDIS was started by Motorola and IBM and later sold to the current Motient data communications firm that runs the DataTAC network for business with up to 19.2Kbps worldwide in metropolitan areas. The wireless standard for the Internet is Wi-FI, a broadband standard for the interior of buildings with a large bandwidth of 54Mbps. There are several Wi-Fi standards and they are evolving. City governments are creating citywide Wi-Fi networks to provide an internet infrastructure that will advance their city. These standards will be linked so that wireless phones can be used over Wi-Fi.
Communications is gradually converging into a single fiber optic and
wireless worldwide network for all types of communication. To
understand the problems in creating this network we need to
understand the concept of information from the perspective of
communication engineers. This concept enables communication engineers
to design communication networks with enough capacity to carry the
intended messages. It also provides a theory to obtain the maximum
compression of digital messages.
Shannon in 1949 developed a theory of communication based on a
measure of information which enables communication engineers to
determine the communication capacity required to communicate the
messages. In order to discuss Shannon's measure of the information
content in a message, consider the following simple diagram of a
communication system:
At the information source the input message is digitized and at the
destination the message is converted back into the input form, that is,
text, voice, etc. Noise will cause the output to differ from the input.
To build a communication system, we need to know the volume of the
message. Intuitively, consider a fresh water system in a city. To build
this system you must know the size of pipe to transmit the desired
amount of water to each household. Since we have converted the message
into binary code, Shannon's contribution was to define the message
volume in bits.
To gain some intuitive understanding of his concept we need to
consider some examples. If you had to transmit an infinite string of
1's with no zero's, you can use the string's pattern to greatly
compress the number of bits you must transmit. In this case, once you
remove the pattern there is nothing left to transmit. Now suppose 0's
were placed at random intervals in the string of 1's. You would have
to transmit the pattern of all ones and also transmit the locations
of the zero's. The greater difficulty in transmitting the second
message over the first is directly related to the number of randomly
spaced 0's. Now consider a picture composed of a green field. To
transmit the message all you must transmit is the pattern. The video
message becomes progressively more difficult to transmit depending on
the number of blue dots randomly placed in the picture. The
Shannon information message is a measure of the randomness, or
entropy, of the message. Shannon's measure says nothing about the
meaning of the message. The communication engineer does not care
whether the message is nonsense syllables or national secrets.
Entropy, or randomness, refers to number of bits required to transmit
the random elements. Shannon is very important because he provided
communication engineers with a theory for designing appropriately
sized communication channels for transmitting the information content
of the messages. If the channel capacity is greater than the
information measure (entropy) of the message, it is theoretically
possible to transmit the message without error in a noisy channel. On
the crest and trough of every wave you can place a bit or no bit.
Thus to transmit a message the frequency of channel must be greater
than one half the number of bits which must be transmitted per
second.
Digital communications presents a fundamental problem in that the raw
digitization of analog messages greatly increases their size. One
approach is to use a bigger communication channel to transmit the
digitized message. A better approach to deal with raw digitized
messages is to compress the message using compression algorithms, which
in the case of teleconferencing are called codices. For example, a
telephone conversation is digitized into 64,000 bits/sec. The entropy
measure of a voice message may be less than 1000 bits/sec.
Communication engineers have developed techniques to compress messages
so that the amount of bits is closer to the entropy measure. For
example, telephone conversations can be transmitted by voice recorder
at 2400 baud, a term meaning bits per second. In order to market
inexpensive teleconferencing there are powerful incentives to compress
video messages. The current status is:
|
Type |
Baud (transmission) Rate |
|
|---|---|---|
|
Slides |
1.2K - 56K |
|
|
Poor to medium quality motion |
56K - 1.2k |
|
|
Quality motion |
1.2M - 140M |
|
Check out various types of compression technology:
The market in telecommunications, which is growing rapidly, is in a
state of flux both in terms of corporate structure and in terms of
technology.
Two factors have greatly increased the competition in computing and
communications. First, with communication becoming digital the boundary
between computation and communication has disappeared. Communication
corporations have moved into computation and vice versa. For example,
AT&T bought NCR, a computer firm, and IBM has several
communications ventures. Second, competition in communication has
greatly intensified with the breakup of the Bell system. As you may
know, several years ago the courts broke apart the Bell system into
AT&T(long distance) and the seven baby Bells (local service). Over
time the court-imposed restrictions on the baby Bells have been
eliminated. Some competition between the Bells and the cable TV
companies has begun in that both can now offer high speed internet
access through their respective technologies.
The Telecommunications Act of 1996 opens up all communication to
competition. AT & T split into three firms: AT &T in
communications, Lucent in communications equipment, and NCR in
computers. In Texas, Southwestern Bell, by lobbying, got the state
local competition act to make local competition more expensive for
potential competitors. The Telecommunications Act of 1996 failed to
stimulate local phone competition because the act was fundamentally
flawed. The Baby Bells were supposed to allow competitors to use their
lines in order to compete against the Baby Bells. As an incentive they
were offered the right to compete in long distance communication once
local competition existed. What the Baby Bells did was to merge into
stronger competitors than the long distance firms. They obtained the
right to enter the long distance markets when only nominal local
competition occurred. Competitors must pay the Baby Bells access
charges and the Baby Bells have absolutely no incentive to make
competitors profitable. The act is basically a farce. A much more
daring act would be to make local commucation lines a common carry and
allow firms to compete over the common carrier that would act as a
regulated monooly. Under such a scheme, the Baby Bells would have to
split into a services company and a common carrier company. This is the
route taken with competitive electricity markets. Given the fisaco in
California, I doubt whether this approach with gain much support.
Today, we have some competition in the long distance markets, and the beginnings of competition in the local markets. Competition in the local markets did not come about by firms competiting over the Baby Bells' networks, but rather through competing networks. With VOIP or phone service over the internet, the cable firms have become direct competitors to Baby Bells. Also, many consumers, especially younger consumers have switched to only having a cell phone. The next competitor on the local scene is running the Internet over power lines. This gives another way to deliver cable TV and VOIP phone. The Baby Bells to compete are beginning to implement fiber optic networks that will have a much greater capacity than their rivals.
a. Short Run: The most important fact in the growth of
communications traffic is the rapid rate of data traffic relative to
voices traffic. All communications systems will gradually merge. One
possibility is to merge into the internet using the TCP/IP protocol and
its descendants.
b. Long Run: In your lifetime, computers at all levels may
become 10,000 times as fast as they are now and also increase that
much in memory. At a super computer conference I went to a few years
ago, they were conjecturing about when today's supercomputers would
be desktop computers for engineers. Advances in voice recognition
will make computers much easier to use. New devices such as neural
networks will increase pattern recognition so that languages can be
based on voice recognition of structured English.
Paper as a media of communication is on its way out. All office
equipment is currently being linked into a network so that documents
and data can be transmitted over the telephone system. Paper will
gradually become the secondary media. Existing one time write optical
disks could fulfill the legal requirement for a media which can not be
easily tampered with. This system should be in place in thirty years.
With bandwidth on demand, the phone system becomes a multiple dynamic
interactive video voice communications system called the social nervous
system. By the social nervous system we
mean:
a. A broadband digital communication system capable of carrying any
media-voice, data, symbols, or video which links every home and
office.
b. Every home and office would have at least one smart terminal
capable of handling all the various media.
c. All man's knowledge or recorded experience whether in the form of
documents, books, video, or sound cassettes would potentially be
available from any terminal (provided the individual has access).
d. Electronics will replace paper as the primary media for text. One
time write optical disks will become the legal media for recording
important documents.
The speed at which such a system is installed depends on economic
incentives. For example, currently optical fiber is about as cheap as
copper wire. Hence, new subdivisions will be increasingly wired with
optical fiber as opposed to copper to anticipate the future system.
With the lifting of the restrictions on the phone companies, they
should move quickly to replace the existing copper wire system with a
fiber optics system into every residence in order to sell video
services. My forecast is that in 20 years broadband communications
supporting all types of communication will be as common as narrowband
phone communications is currently.
The usefulness of the existing copper wire phone system depends
on the speed of modems. Check out The
DSL Forum. This modem can get quite wide bandwidth
through copper wires. The two types of communication technology you
need to understand are:
There are also a large number of sites discussing communications policy. Check them out.
With vast amounts of personal and corporate information in databases
being transmitted through communication systems, there is a pressing
need for security in computer-communication systems. However, the more
secure you make a computer-communication system from access by hackers,
the harder access becomes for legitimate users. Computer-communication
systems can never be made completely secure against unauthorized users.
Military style encryption, the translation of computer-communication
information into code, is a current trend in computing and
communication. Is all information being used by computers or
communicated between people or machines going to be encrypted?
Currently, there is a major battle between police organizations and
businesses concerning cryptography. The National Security
Administration and the FBI want to be able to tap into any
communications (with a warrant, of course) for the purpose of
catching criminals. They propose a cryptography system developed by
the NSA called a Clipper chip. Computer experts are opposed because
they believe the NSA has a backdoor to easily listen to any
communication message. Also, organized crime would have the resources
to break such a system and steal bank transfers. Businesses generally
want unlimited encryption to protect vital corporate secrets.
Recently the Clinton administration rejected the NSA encryption
scheme.
Increasingly, many kinds of decisions will be made by analyzing alternatives using databases. This will include personal decisions as well as political-economic decisions. Man, as a decision maker, has limited cognitive skills. This limit has been called bounded rationality by the Nobel laureate H. Simon. Using decision aids humans can make better decisions in all aspects of life. Making computer aided decisions requires relevant databases. This raises a fundamental conflict between privacy and property rights versus the data needed for making better decisions. Computer based decisions make the information structure or what information should be available for each type of decision a fundamental policy issue. For example, credit data bases enable stores to determine a consumer's credit rating quickly at low cost. This is the basis for the credit oriented consumer market. Without such databases it would be much more difficult to obtain auto and home loans.
With the channel capacity expansion of the communication system, the
cost of transmitting a bit of a message will fall at a rapid rate.
Types of communication requiring higher baud (bits per second) rate,
for example, video, will gradually become more commonplace.
Technological advances may decrease the cost of transportation, but not
nearly as much as technological advances will decrease the cost of
communication. Thus, one would expect a substitution of communication
for travel. Modern society is organized around the automobile. Most
people live within a 20 minute commute from work. This means the auto
transportation system is built to handle the peak morning and evening
traffic loads. During the rest of the day, the system has considerable
wasted idle capacity. Moreover, autos are one of the principal sources
of pollution. In areas such as Denver and LA inversion layers create
social costs in the form health problems in the respiratory system.
Also, communication requires much less energy than transportation. For
these reasons, society would be better off with less commuting.
Prior to the first industrial revolution, most people worked out of
their homes. In industries such as cloth manufacturing, the merchant
took raw wool to farmers' cottages to be spun into thread. Then the
merchant picked up the thread and took it to the weavers cottage to
be woven into cloth. The merchant then took the cloth to another
cottage to be dyed. Work was brought to the home and artisans
generally had their homes attached to their shops. The custom of
commuting to work began very recently. As automation of manufacturing
proceeds, work will increasingly involve the manipulation of
informational objects. As the manipulation takes place through a
terminal, the substitution of communication for travel depends on how
effective groups can be at accomplishing tasks through communication
networks.
How we physically locate people in an organization for effective
problem solving requires experiments to find out how people
communicate in problem solving. Currently in large organizations
there is much decentralization in location. The issue is: Given all
our new communication/computing equipment, what activities can be
accomplished effectively remotely?
In one experiment, two groups in separate rooms were tested in the
speed at which they could solve simple problems:
i. Assembly of a trash can carrier when one group had the parts and
the other the instructions.
ii. Find all the citations relevant to an article when one group has
the article and the other the index.
iii. Find the closest physician when one group has the address and
the map while the other group has the list of physicians.
The two groups could communicate:
i. Communication rich: voice and video.
Ii Voice.
Iii Hand written messages.
iv. Typing: inexperienced.
v. Typing: experienced.
The results indicated that to solve problems:
|
Message |
__Rich__ |
__Voice_ |
__Hand__ |
__Type__ |
|---|---|---|---|---|
|
Ave Time |
29 |
33 |
53 |
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There are many types of teleconferencing. The oldest, simplest,
and cheapest type of teleconferencing is a conference phone call.
Advances in teleconferencing are proceeding in two directions. One
approach is in teleconferencing taking place in special
teleconferencing rooms or with special equipment and the other is in
teleconferencing in computer networks via desktop computers.
Let us first consider special teleconferencing rooms or equipment. In
this approach a more advanced type is voice and slides, and the most
advanced type is video teleconferencing with dynamic video, voice,
and data. In 1982, ARCO spent $20M for a teleconferencing system
because the chairman traveled 600 to 700 miles everyday for the past
35 years. ARCO's system includes one TV screen for pictures and one
for data (Alaska to LA) and they also plan to expand network and
transmit data from seismic tests. Video teleconferencing is growing
at 20 to 40% a year. With increased long distance communication
competition through the creation of fiber optic networks with
tremendous excess capacity rates should continue a downward trend. As
the demand for teleconferencing services increases, producers obtain
economies of scale in production. For example, to reduce the cost of
full video conferences, one company has set up a video conference
'coop' to sell the unused time at facilities set up by corporations.
Later, Aetna set up video conference rooms to link its corporate
center with its data processing center which were 15 miles away. It
cost $250,000 to build and cost $250/hr to operate. Before Aetna set
up this system, 500 programmers met 3000 times a month with managers
in the headquarters. Aetna has installed video conference rooms in
its Chicago, San Francisco and Dallas offices. By 1986, a typical
video conference rooms center cost more than $200,000. A year later
the cost fell to $120,000 and by 1989 to $60,000. The cost is
projected to be below $15,000 by the end of 1993. At the same time
the cost of phone lines for video conference rooms has fallen from
$1600 to less than $20 per hour.
A form of teleconferencing in computer networks is called
collaborative computing. Lotus Notes is an example of software which
allows groups to work together. You should in the next few years
expect a large number of software packages which allow groups of
people at remote personal computer locations to exchange text, data
and still images. PC manufacturers are now creating PCs which
incorporate a videocam for videoconferencing through computer
networks. Such videoconferencing will become commonplace in LANs
before WANs. This may not become commonplace in WANs until the
capacity of the phone system expands to cheaply handle desktop
videoconferencing.
Low cost video teleconferencing offers businesses many advantages.
Teleconferences generally can be set much more quickly than business
meetings involving people at large distances. In addition,
teleconferencing is cheaper than travel. Moreover, executives are
more effective not having to work in airplanes and hotel rooms. A
success story with teleconferencing is M/A Com. Teleconferencing is
used to manage 26 companies. Teleconferencing links small office in
Boca Raton, Fla to four M/A Con centers in San Diego,CA; Catawba,
N.C.; Germantown, MD; and Burlington, MA. The company is also a
vendor of teleconferencing systems that make use of its satellite
link. Instead of two to three days to arrange cross country meetings,
thirty minutes is required to arrange teleconference meetings. What
this means is that M/A Con can respond very quickly to changing
market conditions. Yes, not all businesses are jumping into
teleconferencing. Many will wait until substantial savings have been
demonstrated by the leaders.
Various forms of teleconferencing are also being created in computer
networks. The simplest is the chat mode of information utilities.
More advanced versions of text teleconferencing are in widespread
use. One example is the US Army Missile command. Currently,
communications companies are creating video teleconferencing systems
in computer networks. For example, Northern Telecom has developed the
Visit system which is an $3899 addon to a PC or Mac. This system
provides a separate window for the image of both parties on both
screens delivering 8-14 frames per second. In addition, both
participants can bring up a drawing or document in a shared
workspace. As multimedia PCs become commonplace video conference
rooms will be accomplished with an installed video camera and a board
for transmission and reception for less than a thousand.
Forecast: From 2005 to 2010 teleconferencing will explode because of advances in equipment, the desire of firms to reduce travel costs, and the threat of terrorists blowing up airplanes. Teleconferencing technology will integrate:
In the 70's a research group lead by J. Niles demonstrated that by
using existing technology, corporations such as insurance companies
could decentralize into a group of local offices connected by
communications and be just as effective. The major advantage to
decentralization is much less distance to commute by workers which
results in much less smog.
In London, Mrs. "Steve" Shirley organized F International Ltd., a
company where everyone works at home connected through terminals.
This software firm does $5M a year business and most of the workers
are women with children. Telecommuting enables F International to
obtain skilled workers who otherwise would not be able to participate
in the workforce.
Telecommuting does not bring positive benefits to all participants.
Generally, professionals benefit from telecommuting because they can
have a wider choice in lifestyles. For example, a couple of years ago
Business Week reported on a partner of a Chicago law firm who
telecommuted from Telluride, Colorado. Phone calls were automatically
rerouted to Telluride. If he was called before 10am, he could make a
business meeting in Chicago that evening. Towns in Colorado are so
interested in acquiring telecommuters they are installing better
communications to attract them. Compaq made its salespeople telecommute
with both corporate and personal success.
In contrast, clerical workers frequently do not benefit from
telecommuting. Business managers have used telecommuting as a device
to eliminate fringe benefits and place telecommuters on piecework
wages for typing and so on. There have been law suits against this
practice.
Telecommuting will increase as automation displaces people from
manipulating physical objects and the channel capacity of the
communication system makes video communication inexpensive. With the
TV flat screen which is just coming online currently, you could have
a wall with multiscreens for each participant in a conference. Most
critics of telecommuting do not perceive the impact of the vast
increase in channel capacity. New social customs will evolve for
telecommuters, however, this will take time. The cottage workers who
did not want to work in the textile factories tried to destroy them.
There is generally a tremendous resistance to social change.
The major growth in telecommuting will not be in full time
telecommuting but in part time telecommuting. With the rapid advance
in wireless communication, notebook computers and other portable
electronic gear, individuals can link up with their offices from any
location. This means they only have to be in the office for face to
face meetings. Corporations are going to promote telecommuting in
cities with dirty air because of provisions in the Clean Air Act of
1990. Thirteen cities with dirty air must increase the average number
of riders per car from 1.3 to 1.5 to prevent 3.5 million tons of
carbon from polluting the air by the year 2000. Telecommuting
satisfies the requirement for increasing ridership.
What is fueling the growth of part time and full time telecommuting is the growth of broadband communications, such as DSL and RoadRummer into homes. A current estimate of the number of teleworkers is 20 million. My daughter when she worked for I2 in software sales could pick her home city. She did all her work through her laptop and meet with her sales team at client presentations.
There are numerous sites for teleconferencing and telecommuting. Check them out.
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