Tdc 464 Converged Multimedia Networks - Lecture 1

Front 1

What is telecommunications according to dictionary?

Back 1

(used with a sing. verb) the science and technology of communications at a distance by electronic transmission of impulses, such as by telegraph, cable, telephone, radio, or television.

(used with a pl. verb) The electronic systems used in transmitting messages, as by telegraph, cable, telephone, radio, or television.

Front 2

When was last telegram sent?

Back 2

early 2000's

Front 3

What did acronym AT&T used to represent?

Back 3

American Telegraph and Telephone

Front 4

What is telephony?

Back 4

The transmission of sound between distant stations, especially by radio or telephone.

Front 5

What is IP Telephony

Back 5

The transfer of sound over the IP network

Front 6

In the US telecommunications is highly regulated by

Back 6

Federal Communications Commission (FCC) and by State Commission

Front 7

What are the important events in the US regarding telecommunications?

Back 7

1984 AT&T Divestiture & the 1996 Telecom Act

Front 8

What was the primary objective of the 1984 Divesiture?

Back 8

Open the market for long distance compeitiion

Front 9

What was the primary objective of the 1996 Telecom Act

Back 9

Opened the market for local market competition

Front 10

What are the characteristics of International Telecom Industry

Back 10

After 90's moving towards privitatization. However, privatization does not mean more competition. In many countries there are monoplies with one or two companies owning the entire industry.

True competition requies three or more companies for customers to choose in most markets

Front 11

Why are telecom standards important?

Back 11

Standards are extremely important for interoperability between products from different vendors

Front 12

Why are international telecom standards important?

Back 12

International standards are important for phone calls between countries.

Front 13

Who are the standard bodies?

Back 13

Primary bodies are ANSI for US and ITU-T for International. Anything related to IP comes from IETF

Front 14

What is the difference between telecom and datacom?

Back 14

Signaling (telecom) vs. protocol (datacom)
The OSI 7-layer model is applicable to both telecom and data com.

Front 15

What happen on the following dates;

1847:
1876:
1878:
1881:
1885:
1893: .
1896:

Back 15

1847: Alexander Graham Bell was born in Ediburgh, Scotland.
1875: a gallows phone was developed
1876: 1st telephone call (03/10)
“Mr. Watson, come here, I want you.”
1878: 1st telephone exchange office
1881: 1st long distance line, 45 miles (Boston and Providence)
1885: AT&T incorporated in New York
1893: Patent expired. Anyone can start a phone service company.
1896: Dial phone. The concept of switching was introduced, but there is no switching system.

Front 16

What happened on the following date;

1908:
1913:
1915:
1919:
1925:
1929:
1934:

Back 16

1908: Bell System: One Policy, One System, Universal Service.
1913: Kingsbury Commitment. AT&T committed to Attorney General that it would provide long distance connection for independent phone companies.
1915: 1st transcontinental line from NYC to SFO.
“Mr. Watson, Come Here, I want you.”
1919: 1st telephone switching system in service. (Norfolk, VA)
1925: Bell Telephone Laboratories
1929: President Hoover got his phone on his desk.
1934: Communications Act – interstate phone business is regulated by FCC

Front 17

What is important about the following dates;


1938:
1949:
**1956:
1965:
1971:
1974:
1976:

Back 17

1938: 1st crossbar central office switch
1949: Anti-trust suit against AT&T by Attorney General
1956: Judgment limiting AT&T business to common carrier communications and government projects.
Phone services only, no computer business, no TV, nor anything else.
1965: eavesdropping is unconstitutional.
1971: Bell Systems served 100M lines. Independent telephone companies served 25M lines. Other countries had 160M lines in total.
1974: An anti-trust suit against AT&T by DoJ.
Separation of inner city facilities from local facilities
Separation from service providers from manufacturer
1976: 1st digital switching system

Front 18

What is important about the following dates;

1984:
1986:
1988:
1996:

Back 18

1984: AT&T Divestiture
AT&T Long Distance + Manufacture
Seven Regional Bell Operating Companies (RBOC)
Who were these 7 Baby bells?
Who are they now?
Competition of Long Distance Market
AT&T can enter into the computer market.
IBM can enter into the telecommunications manufacturing market. (bought ROLM)
1986: 1st round “Equal Access” completed by RBOC
1988: Commercial offering of ISDN services
1996: Telecommunications Act

Front 19

What were the 7 RBOC's

Back 19

Pacific Bell
Ameritech
Southwestern Beel
US South
US West
Bell Atlantic
Nynex

Front 20

What companies now comprise AT&T (SBC)

Back 20

Pacific Bell
Ameritech
Southwestern Beel
US South

Front 21

Which RBOC's became Verizon?

Back 21

Bell Atlantic
Nynex

Front 22

Which RBOC is now Quest

Back 22

US West

Front 23

Who are the incumbent Local Exchange Carriers (ILEC's) ?

Back 23

AT&T, Verizon, and Quest

Front 24

Show diagram local service before 1984

Back 24

Front 25

Show diagram of Toll Call before 1984.

Back 25

Front 26

Show the architecture post 1984 for the PSTN. What is the primary difference pre & post

Back 26

LEC and IXC are separate companies

Front 27

What determines if a call is local or long distance?

Back 27

LATA: Local Access and Transport Area
Note: inter-LATA calls are known as long distance calls, and RBOCs were not allowed
to offer long distance services until recently.

Long-distance calls has nothing to do with area codes

Inter-lata calls must be serviced by a long distance carrier.

Front 28

What is meant by the term equal access?

Back 28

The LEC must provide equal access for IXC's. In 1984 the large IXC's were AT&T, MCI and Sprint

Front 29

Show a diagram of an Interlata call including the POP

Back 29

Front 30

Telecommunication Act of 1996 Summary

Back 30

“To provide a pro-competitive, de-regulatory national policy framework designed to accelerate private sector development of advanced telecommunications and information technologies and services to all Americans”

Front 31

Telecommunication Act of 1996 included

Back 31

remove entry barriers to allow local phone competition
CLECs (Competitive LEC) vs ILECs (Incumbent LEC)
allow LEC’s to provide long distance service (in their region) after “opening up” their region to competition
checklist defined as criteria for “opening up” region to competition
allow LEC’s to manufacture telephone equipment
deregulated Cable Television service (removed 1992 Cable Act regulations)

Front 32

Who are ILEC's

Back 32

AT&T, Verizon, Quest, Embarq and Windstream

Front 33

What is a CLEC? What are the two types of CLEC's?

Back 33

Facility-based & Reseller

Front 34

Do we have competition for local service?

Back 34

Yes. VoIP Comcast is the largest VoIP provider in the US.

Front 35

Show the diagram for the Central Office Environment

What is the Signaling System called?

Back 35

SS7

Front 36

What is the connection between a phone and switch called?

What is the connection called between a PBX and a switch?

What is the connection called between two switches associated with the same CO?

What is the connection between two CO switches called?

Back 36

What is the connection between a phone and switch called? Line

What is the connection called between a PBX and a switch? Line or Trunk

What is the connection called between two switches associated with the same CO? Intra-office trunk

What is the connection between two CO switches called? Interoffice trunk

Front 37

Give some examples of Customer Premise Equipment (CPE)

Back 37

Customer Premise Equipment (CPE) is any piece of equipment supplied by the customer to interface with the PSTN. Examples are:
Single Line Telephone Set
Multi-Line Telephone Set
Key Telephone System (KTS)
Private Branch Exchange (PBX)
Channel Bank (CB)

Front 38

Show a diagram of a voice network, Include the four types of networks

Back 38

Switching Network -- Class 5 or 5ESS telephone switch in the CO

Access Network -- are the lines and/or trunks from the CPE to the CO switch

Transport Network -- Are usually the optical network between the CO switches

Managment Network -- Outside the scope

Front 39

Show a diagram of the Public Switched Telephone Network

Back 39

Front 40

What is the common denominator between a called placed between Comcast and Vonage phones?

Back 40

The PSTN.

Both Comcast and Vonage connect to the PSTN.

Front 41

Why do we need the PSTN in the middle? Why do we need convert IP to TDM and TDM-to-IP?

Why can't Comcast and Vonage customer connect to one anther directly without the PSTN?

Back 41

The PSTN provides the signaling that allows Comcvast and Vonage to communicate

Front 42

What is IMS?

Back 42

IMS – the IP Multimedia Subsystem – developed originally by the 3G mobile community, is now seen by many service providers (not just by vendors) as the key to migrating legacy wireline networks towards IP, next-generation networks, and voice over IP.

Front 43

Is DSL covered in the Telecom ACt of 1996?

Is the LEC required to share DSL service

Back 43

FCC says yes. SBC says No.

FCC and SBC agrees that do not have to offer DSL

Front 44

What is the difference between the data network and voice network?

Back 44

The architecure is the same. The CPE is different. For example, cable modem vs a telephone

Front 45

In what circumstance will the technology for access network for data be the same technology as the access network for voice?

Back 45

When the CPE is DSL. This is an example of multiplexing.

Front 46

What is BGP?

Back 46

Border Gateway Protocl (BGP) is routing protocol that allows service providers to send and receive data from one another

Front 47

What is a peering agreement?

Back 47

Large service providers agree to route each other data traffic

Front 48

What is a converged or integrated network?

Back 48

Answer: single facility for both voice and data traffic

Technical solution: TDM, ATM, and IP

First Step: digitized the voice

Front 49

What is one of the first services to use the same physical facility for voice and data communication

Back 49

ISDN

Front 50

What types of converged services have been available for many years are used as part of the PSTN backbone?

Back 50

SONET and ATM

Front 51

Does Integrated Services require IP?

Back 51

No. Integrated services does not require IP, which is one of protocols supporting integrated services.

Front 52

Why - Integrated Service

Back 52

Cost

The concept of integrated service is not new.
Carrier prefer a single network supporting both voice and data traffic.
Enterprise also prefer this way.
Solution proposed:
ISDN
B-ISDN – what is B-ISDN?
Why did they fail? Or, do they really fail?

New service create new revenue opportunities

Front 53

Create a diagram that depicts Integrated Services on the Access Network

Back 53

Front 54

Show the first generation for Integrated Services using TDM

Back 54

Front 55

Show diagram of Integrated Services using ATM

Back 55

Front 56

What is important to know about ATM based Integrated Services solution

Back 56

Front 57

What is the main issue with TDM services?

Back 57

Ineffeciency of the network bandwidth

Front 58

What are the challenges of VoIP?

Back 58

PSTN.

PSTN is good, reliable and cheap

Front 59

Does VoIP offer comparable services as PSTN?

Back 59

No.

Over 1000 features on 5ESS. VoIP does not have same feature set as PSTN

Front 60

Does VOIP offer comparable quality as PSTN?

Back 60

Yes and No.

Front 61

Does VoIP offer comparable pricing as PSTN?

Back 61

PSTN is really really cheap. Very difficult to compete with the low prices

Front 62

Why VoIP?

Back 62

IP is widely available.
IP is a connectionless service
Voice must be carried in a circuit or a virtual circuit
IP is engineered for data traffic
Data integrity is important.
Latency is not a major concern for data traffic.
Traffic is asynchronous.

Front 63

Do we really need QoS?

Back 63

Is needed if there is competition for bandwidth.

One solution is priority, which is QoS. Another solution is increase the bandwidth

Front 64

Why VoIP?

Back 64

“If it is not broken, don’t fix it”
some truth to this statement
telephony is not “broken”
so what is “broken”?
Why carry voice over IP?
Internet has provided NEW SERVICES
There are potential $$$ in carrying voice over IP
Integration: one network for both voice and data traffic
Price (does it save money?) and performance (does it offer better services – quality and features?)
New features lead to new revenue opportunity

Front 65

Are Equipment Cost higher or lower with VoIP?

Back 65

CO telephone switches are proprietary.
PBX are generally proprietary.
Difficult to deploy 3rd party software
Not many choices of telephone until 1984.
IP networks
Open standards
Competition
Moore’s Law tends to motivate data networking

Front 66

What are the Advanced Services capability with VoIP?

Back 66

Some inherent characteristics of IP
Voice Virtual Private Network (VPN)
What is voice VPN?
Number Portability
Advanced user interface
with HTML (point-and-click) are much easier to deal
Unified messaging service
Can you get your voice mail from your e-mail?

Front 67

Describe the lower bandwidth requirements with VoIP

Back 67

DS0: 64 kbps – legacy networks (PCM)
Could be reduced to 32 kbps (ADPCM)
G.711: 64 kbps
G.729A: 8 kbps
G.723.1: 5.3-6.3 kbps
take advantage of low-rate vocoders
What is the significance of bandwidth reduction?

Front 68

AT&T U-Verse – is it VoIP?

Back 68

U-Verse based on VDSL. Supports up 20Mb. The U-Verse box has a POTS and Ethernet. Since the U-Verse supports SIP its likely that the voice is carried VoIP

Front 69

Verizon FiOS – is it VoIP?

Back 69

FIOS is fiber to the home. FIOS uses GPON. GPON uses multiplexing to carry voice and data. Separate channels carry data and voice. So this solution does carry voice traffic as VoIP

Front 70

3G – is it VoIP?
Dual mode - what does it mean?

Back 70

No.3G is dual mode. Voice and data are carried over different channels

Front 71

4G
WiMAX (802.16) – is it VoIP?
Long Term Evolution (LTE)

Back 71

4G does not support voice. So it must be VoIP

Front 72

Back 72

No

Front 73

What are the VoIP Challenges

Back 73

Speech Quality
Traffic Prioritization (Quality of Service)
Network Reliability and Scalability
Location Based Services (e.g., E911)
Security

Front 74

What is the perception of the telephone network?

Back 74

It is always available

Front 75

5 9’s availability. What does it mean?

Back 75

No more than five minutes of downtime per year

Front 76

What is the perception of the data network?

Back 76

??

Front 77

What is the typical service level agreement (SLA) for data services?

Back 77

No more than four hours of downtime per month.

Front 78

What are the reliability requirements for router/switch?

Back 78

??

Front 79

Scalable vs. non-scalable
Give an example of each for router

Back 79

Scalability growing the network without major infrastructure changes

Front 80

What are the characteristics of voice and data traffic?

Back 80

Voice: sensitive to delay
Data: sensitive to bit error

Front 81

If voice and data are carried on the same physical link, how do we prevent the data traffic from congesting the network which will cause long delay and packet loss on the voice traffic.

Back 81

??

Front 82

What is QoS? Does IP support QoS?

Back 82

Prioritaztion of voice traffice over non voice traffic. Yes

Front 83

Data traffic is usually best-effort service

Back 83

??

Front 84

VoIP Regulation

Back 84

Regulation
Location Based Routing (1-800)
N11 services
E911
CALEA – wiretapping
Communications Assistance for Law Enforcement Act

Front 85

Numbering Plan

Back 85

What is the numbering plan for VoIP

Front 86

Network convergence: from two separated voice and data networks into a single network

Back 86

Carrier Core Network
Carrier Access Network
Enterprise Network
Residential Network

Front 87

IP – the common denominator

Back 87

The industry is moving in this direction but very slowly.

Front 88

Note that there are still over 100 million traditional telephone lines in U.S.
What does it mean to the VoIP equipment vendors and service providers?

Back 88

??

Front 89

What do customers want?

Back 89

Dial Tone
Public Phone Number - why is this important?
E911
Voice Mails
Call Features (Call waiting, call forwarding, etc.)
N11 ??? do you need 211/311/411?
Detailed billing? Detailed call records?

Front 90

Which of the N11 services are required by the FCC

Back 90

No. Only E911 is required by FCC