Lecture#9 Concluding session, part I The Bonch-Bruevich Saint-Petersburg State University of Telecommunications Series of lectures “Telecommunication networks”

Lecture#9

Concluding session, part I

The Bonch-Bruevich Saint-Petersburg State University of Telecommunications

Series of lectures “Telecommunication networks”

Instructor: Prof. Nikolay Sokolov, e-mail: sokolov@niits.ru

Main definition

Telecommunication. “Any transmission, emission or reception of signs, signal, writing, images and sounds or intelligence of any nature by wire, radio, visual or other electromagnetic systems“.International Telecommunication Conference, Atlantic City, 1947.

Black box

Controlling subsystem

Controlled subsystem

Instructions Reports

Black box

Input Output

A(t) D(t)

B(t)

Management C(t)

To

take

To

carr

y

Communication effectiveness

Form of communication

Com

mun

icat

ion

effe

ctiv

enes

s

2 people at whiteboard

2 people on phone

2 people on mail

Videotape

Audiotape

Paper

Telecommunication system

Customer Premises Network

Access Network Core Network Service Nodes

Responsibility of the Telecom Operator

This model is proposed by ITU-T for the GII (Global Information Infrastructure). On the other hand, this model is useful for any telecommunication network.

Definitions of term “Network”ITU-T, E.164 (2005): Internationally interconnected physical nodes and operational systems operated and maintained by one or more ROAs (Recognized Operating Agency) to provide public telecommunications services. Private networks are not included in this definition.

ITU-T, G.998.1 (2005): All equipment and facilities, including loop plant, located on the carrier side of the network interface.

ITU-T, G.805 (2000): All of the entities (such as equipment, plant, facilities) which together provide communication services.

ITU-T, Y.101 (2000): A set of nodes and links that provide connections between two or more defined points to facilitate telecommunication between them .

International Telecommunication Union

ITU is the leading United Nations agency for information and communication technologies. As the global focal point for governments and the private sector, ITU's role in helping the world communicate spans 3 core sectors: Radiocommunication, Telecommunication Standardization and Telecommunication Development. ITU also organizes TELECOM events and was the lead organizing agency of the World Summit on the Information Society.ITU is based in Geneva, Switzerland, and its membership includes 191 Member States and more than 700 Sector Members and Associates.

ETSI

ETSI was created by CEPT (European Conference of Postal and Telecommunications Administrations) in 1988. Based in Sophia Antipolis (France), ETSI is officially responsible for standardization of Information and Communication Technologies (ICT) within Europe. ETSI has 696 members from 62 countries/provinces inside and outside Europe, including manufacturers, network operators, administrations, service providers, research bodies and users — in fact, all the key players in the ICT arena.

Maslow's Hierarchy of Needs (1)

Abraham Maslow developed the Hierarchy of Needs model in 1940-50s USA, and the Hierarchy of Needs theory remains valid today for understanding human motivation, management training, and personal development.

Maslow's Hierarchy of Needs (2)

Tel

eph

one

con

vers

atio

ns

Telephone communications system

"Telephone communications system" term is usually refers to base principles of telephone network’s construction, operation and development. These principles usually include the following positions:•purpose of the system;•supported services;•network structure;•quality of service ratings;•numbering plan;•maintenance;•equipment requirements;•main directions of system development.

Revenue distribution

Mobile communications

Transit of traffic

Local telephone communications

Other services

Internet (access)

International and long-distance

communications

Market evolution

Source: ITU80

70

60

50

40

30

20

10

0

Mobile contractsInternet usersFixed telephone linesMobile broadband access contracts

Fixed broadband access subscribers

Per 100 people

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009Year

Distribution of the amount of calls during the day

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 0

Time of day

Amount of calls

In the PSTN, required bandwidth is identical for any connection.

Traffic on a Monday morning

Equipment evolution

Switchers

XX century

Time

Access Networks

FTTx

xDSL

BWA

Manual exchange

Step-by-step exchange Crossbar exchange

Digital exchange

NGN

.

.

.

Single-wire line(voice channel)

Two-wire line(voice channel)

Bro

adba

nd c

hann

el

Time

XX century

XXI century

XXI century

Access network (1)

20%80%

20%80%

Remote module

a) model of the old subscriber line

b) model of the modern subscriber line

Fiber optic cable

conversion “о/е” and “е/о”

Distribution cabinet

Main distribution

frame

Main distribution

frame

Multipair cableDis

trib

utio

n bo

xD

istr

ibut

ion

box

Ter

min

alT

erm

inal Pho

ne ja

ckP

hone

jack

Access network (2)

Remote moduleFiber To The Remote (FTTR)

Main distribution

frame

Dis

trib

utio

n bo

x

Ter

min

al

LR

Distribution cabinet

Dis

trib

utio

n bo

x

ADSL (up to 8 Mbit/s) or ADSL2+ (up to 24 Mbit/s)

e.g. VDSL2 (up to 100 Mbit/s)

Fiber To The Premises (FTTP)

LP BP>100 Mbit/s

Ter

min

alT

erm

inal

Optical fiber

Spectral range

First data transmission systems for the mainframe

Mainframe Mainframe Data Link

Mainframe

Terminal

Terminal

Terminal Subscriber Line

Subscriber Line

Subscriber Line

a) Connection between two mainframes

b) Connections for terminals

Traffic growth

Internet (RFC 3935 )The Internet: A large, heterogeneous collection of interconnected systems that can be used for communication of many different types between any interested parties connected to it. The term includes both the "core Internet" (ISP networks) and "edge Internet" (corporate and private networks, often connected via firewalls, NAT – network address translation – boxes, application layer gateways and similar devices). The Internet is a truly global network, reaching into just about every country in the world. The IETF community wants the Internet to succeed because we believe that the existence of the Internet, and its influence on economics, communication, and education, will help us to build a better human society.

Example of the Internet network structure

AS1AS2

AS3

AS4AS5

AS – Internet autonomous system

Interconnection of two local networks

R

R

R

R

R

R

R

R

R

LAN LAN

R – router, LAN – Local Area Network

Forecast of the access demands

Year

1995 2000 2005 2010 2015 2020 2025

Households, %100

80

60

40

20 1.5 Mb/s

6 Mb/s

24 Mb/s

100 Mb/sSources: Alcatel Telecommunications Review, 2nd Quarter 2003, Telektronikk, Volume 100, No. 4, 2004.

Internet in our life

Research company “Yougov” carried out survey among broadband Internet users in Great Britain. The main goal was to define goods and services that citizens will be eager to sacrifice during economic depression. Approximately 3% of the respondents were ready to save money by limiting expenses on Internet access. About 30% of respondents (near 5 million) were ready to cut down expenses related to newspapers & magazines, alcohol, cigarettes but will use Internet. On the other hand, only 60% of respondents were going to use services from their Provider. Remainder will find Provider with inexpensive services.

Cellular topology with seven different frequency ranges

6F

5F 7F

1F

4F

3F

2F

5F

4F

6F

7F

1F

3F

2F

R

D

Handover and roaming

MSC1 MSC2

PSTN

. . .

BS11

BS12

BS13

T

Interworking functions

Network 1 Network 2

BS21

CO1

Main elements of the network

Mobile terminal

Radio subsystemSwitching subsystem

Intra-network interfaces

Air interface

Internetwork interface

Other network(s)

Interfaces

F E

C

G

B

A

Abis

Um

MS-SIMMS

SIM

BTS

BSC

MSC

EIR MSC

VLR

VLR

HLR

D

MSC – mobile switching center

MS – mobile station

BTS – base station

BSC – base station controller

EIR – equipment identification register

SIM – subscriber identity module

HLR – home location register

VLR – visited location register

Typical structure of the radio and television broadcasting networks

Served area

Main Center

Regional Center

Regional Center

Regional Center

Local Centers

Main path Main path

Main path

Standby path

Classification of the television broadcasting systems

Television broadcasting

On-air broadcasting

Analoguechannels

Digital channels

Standard quality television

High definition television

Cable television Satellite television Combined system

One-way broadcasting

Interactive television

Cycles in the telephone communication development

Milestones of telephony development

Time

Emergence of the telephone communications

80s of the XIX century

Automation of the telephone communications network

20s of the XX century

Utilization of the program control

60s of the XX century

Transition towards packet transmission and switching technologies

Beginning of the XXI century

The main goal is the real demands of each customer!

The Death of Distance *)

*) F. Cairncross. The Death of Distance. – Harvard Business School Publishing, 1997.

Year

Falling costs

100

80

60

40

20

0

1920 1930 1940 1950 1960 1970 1980 1990

Ocean freight

Satellite charge

Transatlantictelephone call

Air transport

Source: World Development Report 1995, World Bank

Integration, convergence, and consolidation (1)

Integration is aggregation or interpenetration. In some cases, integration is considered as creation of the relationships.

Convergence is a process by which unrelated organisms independently acquire similar characteristics while evolving in separate ecosystems. In telecommunications (according to ITU-T Q.1761), coordinated evolution of formerly discrete networks towards uniformity in support of services and applications. It means convergence is approximately the same as integration.

Consolidations is a reasonable combination of the integration and convergence.

Integration, convergence, and consolidation (2)

Typical example of integration is ISDN (Integrated service digital network). One network supports the services that were previously provided by number of the existing networks.

Typical example of convergence is the functions of the fixed and mobile networks. Mobile networks support the Internet access. Fixed networks provide the SMS transfer.

Typical example of consolidations is utilization of the common cable lines for the transmission of the different information (voice, data, video).

Integration, convergence, and consolidation (3)

ITU, Recommendation Q.1702, Converged services:

The integration of Internet, multimedia, e-mail, presence, instant messaging, m-commerce, etc., services with voice service.

Sometimes term “convergence” is used instead of word “integration”. Term “integration” was attractive during elaboration of the ISDN concept. Market of the ISDN mostly was not successful. For this reason, number of experts use term “convergence”.

Global Information Infrastructure (1)

Source: ITU-T, Recommendations Y.101 and Y.110

A collection of networks, end user equipment, information, and human resources which can be used to access valuable information, communicate with each other, work, learn, receive entertainment from it, at any time and from any place, with affordable cost on a global scale.

Global Information Infrastructure (2)

Driving forces:

1. Two predominant factors distinguish a situation for the Global Information Infrastructure (GII) which is likely to be radically different from previous information infrastructures. These two factors are:-the convergence of technologies in use within telecommunications, computers, consumer electronics and the move of content provision industries towards digital technology; - new business opportunities, created by the unbundling of services made possible or necessary by deregulation, and other commercial and/or open market pressures.

2. Digitalization (All forms of information, including voice, data or video/image, are simply reduced to streams of digital bits for transfer over a bit-way (or digital network). This represents a possible decoupling between networks and their payloads).

Global Information Infrastructure (3)Driving forces:

3. Value chain models and business opportunities. The following properties of an added-value chain are relevant to ITU-T standardization work:a) Every link and item in an added-value chain, from content to user or user to user, potentially represents a possible business opportunity.b) Every link in the chain establishes sufficient demarcation points to facilitate potential separate ownership and operation to be realized within the context of the entire chain.c) a) and b) are sources of requirements for the definition of standards-based functions and/or interfaces.This model can be used to represent a competitive telecommunications and information provision environment, involving the interconnection of networks in parallel or in series, as well as systems which enhance or modify information content.

Global Information Infrastructure (4)

Definition of the NGN

A Next Generation Network (NGN) is a packet-based network able to provide services including Telecommunication Services and able to make use of multiple broadband, QoS-enabled transport technologies and in which service-related functions are independent from underlying transport-related technologies. It offers unrestricted access by users to different service providers. It supports generalized mobility which will allow consistent and ubiquitous provision of services to users.

http://www.itu.int/ITU-T/studygroups/com13/ngn2004/working_definition.html

Next generation network model

PC1 PC2

TS1 TS2

CU1 CU2CU3

CU4

PS1

PS2

PS3PS4

PS5

PS6

PS7

PS8 PS9

Local Network 1 Local Network 2

Long-distance network

CU – control unit, PS – packet switch, TS – telephone set, PC – personal computer

Integration of the existing telecommunications networks

NGN

Telephone networks

Data transmission networks

Broadcasting networks

Process of the forming of the NGN

Time

T0

Forming of the NGN

Initial stage

Active development

stage

“Saturation” stage

TI T2 T3

Points of the technology change under transition to the NGN

Long-distance IP network

Local IP network

Local IP network

Local network with channels

switching

Local network with channels

switching

TS

IP-TS IP-TS

TS

TSTS

A B

C D

E FInternational IP network

International network with channels

switching

G

Network structure. Some definitions

Network structure

Term is used to describe the method of how data on a network is organized and viewed.

Network architecture

Also referred to as the network model, the network architecture is the overall structure of how a network is laid out. The network architecture is commonly drawn out as a diagram for a visual representation of the overall network. A well designed network architecture helps prevent network bottlenecks and various other issues.

Some authors use term “topology” instead of the word “architecture” because term “architecture” is widely applied in the publications concerning telecommunication protocols.

Examples for the graph with six nodes

a) Star b) Tree

a1

a2a3

a4

a5

a6

a1

a2a3

a4

a5

a6

c) Ring d) Full mesh

a1

a2a3

a4

a5

a6

a1

a2a3

a4

a5

a6

Oriented, unoriented and mixed graphs

a1

a3

a) Oriented graph

a2

a4

a5

a6

b) Unoriented graph

a2

a4

a5

a6

c) Mixed graph

a2

a4

a5

a6

a3 a3c23 l23 r23

Example of finding the Steiner point

a1

a3 a2

l l

l

3

l

Two variants of the ring network construction

a) First structure of transport network b) Second structure of transport network

a1

a2a3

a4

a5

a6

a1

a2a3

a4

a5

a6

Example of the several rings creation

30

810

126

9

4

1

2

∞∞

57

11

Transformation of the optimization problem (1)

Ring I

Ring II

Ring III

Ring I

Ring II

TS TF

Subscript “s” – start, subscript “f” – future

Transformation of the optimization problem (2)

a2

a1 a1

a2

a3 a3

a4 a4

a5

a6

a7

Deleted edge

TX

p7 << p5

p6 → 1

P7 → 0

Rational decision

TX

Capital expenditures

Designed value

Actual data

Upper bound

Time

Cost-performance compromise

If π is very small (e.g. 0.1%) cost of the network will be high. For this reason, cost of service will be supernormal. The number of the users will be small.

If π is very high (e.g. 50%) cost of the network will be relatively small. On the other hand, quality of service will be poor. For this reason, the number of the users will be small as well.

It is obvious there is cost-performance compromise. Therefore we have to define optimum value of the π. This task is the main one among problems of the network planning.

Improvement of the network characteristics

Network planning

Performance measurement

Performance analysis

Network tuning

Instructor: Prof. Nikolay Sokolov, e-mail: sokolov@niits.ru

Questions?

Concluding session, part I