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: [email protected]
Dec 18, 2015
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: [email protected]
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