Exam #1 Flashcards
Telecommunications Overview
Telecommunications
- The science and technology of communication at a distance.
- Not broadcast (Radio/Television).
Signaling relay
-effective over a short to medium distance
Protocaols
Rules that govern network operation
Right of way
Have to have control over the land
weakness to The signaling relay
Not private, weather interference,easy to hack (insecure)
Message code
fire means help
Foot messenger
relayed messages on foot
Chappe’s optical telegraph
- it was ran by the government (french)
- they invested and undertook large projects
- access to right of way
- high fixed costs
Wireless Circuit
utilizes radiofrequency to enable the transmission.
Morse Telegraph
1844
- Samuel Morris code
- digital system
- electrical based
- not a personal communication
- not private/ very expensive
- provided by a monopoly (western union)
Links
transmission facilities
Network
a system of interconnected
elements.
It can be represented by a set of nodes and a
set of linksthat interconnect pairs of nodes
Traffic
the flow of information or messages through the
network
Station equipment
the interface which allows the user
to access the network—wired or wireless telephones,
computers, fax machines, alarm systems, etc., etc.
Circuit
Any line, conductor, or other conduit by which
information is transmitted.
Circuit Electronic
utilizes electrical energy to enable the
transmission.
Circuit Optical
utilizes light (photons) to enable the transmission
Wireless Circuit
utilizes radiofrequency to enable the transmission.
Morse Telegraph synergies with what industries?
Railroad and newspaper
Telephony
voice system- private after automatic switching (Strowger)
-provided on a monopoly basis
At&T grows
-service area covers 80% of households
-long distance monopoly self-dealing through western electric
documented in Walker report in 1937
-wasn’t confronted
Topology
the geometric configuration of a network–
describes the relationship of the links and nodes and stations
equipment
Network Design
Trade-off in cost of building telecommunications networks.
Switching vs. direct connections.
Switching Connections
goes to more than one connection
Direct Connection
pick up the phone and connects to only one line
-The general rule for number of direct
connections needed is. . .
• (n)(n - 1)/2, where n is the number of
stations
• 100 stations would require (100 x 99)/2 =
4950
Start topology
each piece connected to a node has N connections one for each piece of connections
Tree and Branch network
where the station equipment
is connected to a main trunk, by branch wires.
Tree and branch is non-switched network topology
Bus Networks
Two-way communications path using a a shared
communications line.
- Bus network architectures normally have some scheme of
collision handling or collision avoidance for communication
on the bus.
-no control over network, ethernet common
Layered Networks—Internet Topology
1.Internet Backbone
-(National ISPs: AT&T,
Verizon, Level 3, Sprint)
2.Regional Internet Service Providers
3.Local Internet Service Providers
4. Internet Access Facilities
-PSTN CableTV Satellite Fixed Wireless
Dedicated Facilities (Linking College/Corporate Networks to the
Internet).
Physical Network Layers
Local Internet Service Providers
example: frognet
Regional Internet Service Providers
example: OARNet
Internet backbone providers
example: AT&T, Verizon, Level3
1949
Antitrust Suit
What was the Antitrust suits goal?
split off western electric and AT&T stay out of non-telelphone industries
- fizzled until 1956
- AT&T used Sandia Lab involvement to derail the case
1956
consent degree “Final Judgement”
Consent degree “Final Judgment”
-AT&T would stay out of other industries
-protected the computer industry
-AT&T gave Unix Away-Inspired “open Source”
software
-accidentally helped “outside” innovation
-UNIX shows the importance of openness to improving technology.
Another outcome of the consent degree
- AT&T could not provide computers
- competition was promoted in compter industry
Alexander Bell’s Patent Monopoly: Key Decisions
Lease telephone; vertical integration(produce all related products and services-Western Electric, long distance)
Alexander Bell’s Patent Expire
competition, independent telephone companies, private deployment, telephone cooperatives
Theodore Vail
Corporate research, new patents, long distance monopoly, refusal to interconnect, leverage network effects, universal service (compatibility, all households)
1913 Antitrust Action: Kingsbury Commitment
AT&T will interconnect with independents; AT&T will stop buying independents; AT&T will divest Western Union stock. Slap on the wrist-AT&T continues to grow. Competition continued to decline, innovation was under AT&T’s control. AT&T “cooperates with government:encourages regulation; Graham-Willis Act exempts AT&T from Sherman Antitrust
Innovation at Network Edge:
AT&T doesn’t like that people can connect stuff to their network
AT&T stifles innovation at the network edge: Hush-a-phone; carterphone, restrictive tariff provision; Protective Connecting Arrangements. Phone Phreakers hack AT&T’s network from the edge, using gaping security hole of “common channel signaling”
Competition at Network Core
-AT&T stifles competition in the long distance market after microwave technology makes competition possible. Mircowave Communications, Inc. (MCI) battles AT&T before the FCC and federal courts for over a decade
RBOCs battle back
1996 change in law opens the possibility of RBOC long distance
1974
new antitrust suit filed
Goal: split off equipment and long distance resolved in 1982
1982
breaks up AT&T, “Divestiture” in 1984. Splits AT&T into regional local telephone companies (RBOCS) and the long distance provider, which keeps the AT&T name. Competition in long distance and equipment was promoted. Innovation was still an “inside” approach.
The combination of what two technologies improved the quality of their long distant services?
The audion and loading coils.
What did the so-called “Kingsbury Commitment” promise?
It promised that AT&T would divest itself of its holdings in the telegraph company Western Union, which it had acquired in 1910. Furthermore, AT&T promised to refrain from acquiring additional independent telephone companies without approval of the Interstate Commerce Commission, and also committed to allow independent telephone companies to interconnect their networks with AT&T’s long distance network.
What are the three key technological factors that have allowed the internet to flourish?
- Foundation of open and standardized protocols.
- Ability of network providers to easily interconnect their networks.
- Ability of end users to attach a wide variety of devices to the network.
What is the FCC and when was it formed?
The Federal Communications Commission (FCC) was established in 1934. It was formed to replace the radio regulation function of the Federal Radio Commission. (FRC)
In the 1956 settlement agreement between AT&T and the DOJ regarding AT&T monopolizing the manufacuring and sale of telephones and equipment; What were the resulting actions that AT&T had to do?
A):License patents and related technical information
B):Western Electric would only manufacture equipment associated with telephone service C):Stay out of any business other than common carrier communications services
What were AT&T tariffs and what did they prohibit?
Legally binding documents that governed the relationship between AT&T and its customers. They prohibited any “foreign attachments” to the network.
Quiz Questions 1
The Morse telegraph was the first electrical telegraph
Western Union
Telegraph company emerged from the Civil War in the best shape and went on to monopolize the telegraph industry
Quiz Question 2
Marconi received the world’s first patent for the transmission of mores code
Harmonic telegraph
Alexander Gram Bell was working on the harmonic telegraph before he developed the telephone
Theodore Vail
Theodore Vail DID NOT file a caveat or patent related to the telephone
When the Bell patents expired, what was the characterization of the status of telephone service?
Mainly provided in urban areas
Quesion 3
The government DID NOT initially own all telephone facilities in the U.S.
Question 4
Railroads DID NOT fight the development of the telegraph. The telegraph helped the railroad
If a network exhibits a hierarchy:
some nodes are always logically above other nodes
Which of the following best describes traffic on a telecommunications network?
The information that is sent over a network
