Document 2.0 Telecommunication Networks_NGN : Technological Evolution and Ergonomic Revolution

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NETWORK AND SERVICES WORKSHOP
Telecommunication Networks NGN Technological
Evolution and Economic Revolution Xavier Voisin
Dakar, April 18 21, 2005
ITU/EC Regulatory Capacity Building Project for
ECOWAS countries
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NGN - What is it about ?

• NGN - Next Generation Network
• a generic wording created in the US in 1998 to
  designate an architecture combining a packet
  network and the means to handle and control the
  delivery of communication services
• A multi-service packet network making use of
  Internet Protocol end to end
• An architecture and the necessary control devices
  to enable billable communication services over
  the network

3
NGN Technological Evolution and Economical
Revolution

• Definition and Architecture
• Convergence is driving the Revolution
• Market overview
• PSTN Evolution, Class 4 and Class 5 topologies
• Conclusion

4
Traditional circuit switched Network
NATIONAL LEVEL
Transit Network
Meshed network
REGIONAL LAYER
TDM trunks (E1s)
REGIONAL LEVEL
Local Exchanges
LEX LEVEL
Remote Units
TDM Time Division Multiplexing
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Current Telephone network and Internet access
IN application management Servers

IP, ATM
SCP
INAP
Transit
STP
SS7
ISUP
Transit
ISUP
TDM
Local
Local
Access Node
Voice
Data
POTS, ISDN
Signaling
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Main Drivers for Network Evolution
CAPEX/OPEX optimisation
New revenue generation
SS7
Data (IP or ATM)
PSTN (TDM-based)
NB access
BB access
POTS/ISDN
POTS/ISDN
xDSL
Dial-up
H.323/SIP
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NGN drivers

• Services and Applications are the main drivers
• NGN will not immediately replace, but extend PSTN
  and Internet over time Trends
• Capitalise on the installed base to reduce CAPEX
• Optimise network operations to reduce OPEX
• Introduce new applications for new revenues
• New advanced and Multimedia services are key
  differentiators for network revenue generation
• Allowing Network Operators to act as Application
  Service Provider and Retailer
• Allowing Network Operators to offer advanced
  communication services to Enterprises helping
  them to better reach the consumer
• NGN MM is a way to generate revenues from
  broadband accesses

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NGN Architecture Principles (1)Distributed
Architecture
Traditional Circuit Switch
NGN
Service delivery Connection Control
Softswitch
Line Cards
Trunk Cards
Access Gateways
Trunking Gateways
IP or ATM
Switching Matrix
IP Terminals
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NGN Architecture Principles (2)NGN Network
Elements

• Packet networks
• trend is to use IP networks over various
  transport possibilities (ATM, SDH, WDM)
• IP networks must offer guarantees of Quality of
  Service (QoS) regarding the real time
  characteristics of traffic like voice. This is
  possible with IP MPLS (Multi-protocol Label
  Switching) which provides network engineering
  capabilities similar to ATM. Other protocols
  associated to IP like DIFFSERV provide for
  shaping and prioritarization of packets according
  to the type of service to be transported.
• Trunking Gateways
• allows interworking between classical TDM
  telephony network and Packet-based NGN networks,
• converts TDM circuits/ trunks (64kbps) flows
  into data packets, and vice versa

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NGN Architecture Principles (3)NGN Network
Elements

• Access Gateways
• allow the connection of subscriber lines to the
  packet network
• convert the traffic flows of ISDN and analogue
  subscriber access or2 Mb/s access devices into
  packets
• provides subscriber access to NGN network and
  services
• Softswitch/MGC
• referred to as the Call Agent or Media Gateway
  Controller (MGC).
• provides the service delivery control within
  the network
• in charge of Call Control and handling of Media
  Gateways control (Access and/or Trunking) via a
  standardized protocol such as H323, MGCP or H248
• performs signalling gateway functionality or
  uses a signalling gateway for interworking with
  PSTN N7 signalling network
• provides connection to Intelligent Network
  /applications servers to offer the same services
  as those available to TDM subscribers
• it is nothing but a legacy switch without the
  TDM transport matrix !

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NGN Architecture Principles (4)Common Transport
Infrastructure
Todays Public Networks
NGN
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NGN Architecture Principles (5)Layered Model
PSTN/PLMN
IMS UMTS Access
LAN
Fixed BB Access
3G mobile users
Residential users
Enterprise customers
Remote office / SOHO
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NGN Architecture Principles (6) Standards-based
Components
Service Layer
PSTN/PLMN
IMS UMTS Access
LAN
Fixed BB Access
3G mobile users
3G mobile users
Residential users
Enterprise customers
Remote office / SOHO
Remote office / SOHO
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NGN Technological Evolution and Economical
Revolution

• Definition and Architecture
• Convergence is driving the Revolution
• Market overview
• PSTN Evolution, Class 4 and Class 5 topologies
• Conclusion

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The convergence is inNext Generation Network

• A public communication network with
• A layered architecture
• Clear separation of access/transport, media,
  control and services layers
• Standards-based components
• Open interfaces between the layers
• A common, packed-based infrastructure
• Seamless control of multiple transport
  technologies (IP, ATM)
• Interoperability with existing networks (circuit
  and packet, fixed and mobiles)
• New revenue-generating services
• Leveraging broadband access
• Leveraging mobile access as well
• Voice, data and multimedia applications
• Open Service Provisioning model

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Convergence is Happening !

• Voice and Data
• IP Telephony and Telephony-over-IP
• Click-to-Dial, Unified Messaging, etc.
• Fixed and Mobile
• Converged VPN, WLAN, MMS/eMail, etc.
• Network and Terminals
• Thin clients, managed terminals, always-on,
  ambient networks, etc.
• Video-over-DSL, webTV, video conferencing, etc.
• PC, PDA and TV usage
• Game consoles, internet appliances, etc.
• Softphones, IP phones, feature phones, etc.

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Convergence is Happening ! (contd)

• Private and Public
• Managed PBX, IP Centrex, Network Contact Centres,
  etc.
• Intranets, Extranets, Internet
• Postpaid and Prepaid
• Credit check, sub-accounts, budget control, etc.
• One invoice for voice, data, content and goods
• Real-time and flexible rating and charging
• Home and Office
• Teleworkers, road-warriors, nomads, etc.
• Virtual Private Networks, profile roaming, etc.
• Telecom and IT
• Platforms tools, self-management, web-services,
  etc.

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Market Acceptance of VoIP Creates Competitive
Pressure

• Consumer
• Voice bundled with BB access (i.e. Yahoo BB,
  Vonage, Free, BT)
• Prepaid calling card (i.e. Net2Phone)
• Peer-to-peer (i.e. Skype, SIP-client in Windows
  XP)
• Corporate
• Managed IP PBX (i.e. Verizon)
• IP Centrex/Hosted IP PBX (i.e. SBC, Telecom New
  Zealand)
• Voice VPN (i.e. Equant, Sprint, Telenor)

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NGN Technological Evolution and Economical
Revolution

• Definition and Architecture
• Convergence is driving the Revolution
• Market overview
• PSTN Evolution, Class 4 and Class 5 topologies
• Conclusion

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OPEN Market Drivers Market Forecast
2003 NGN MARKET 1.7 bEuro IP Media GW
660 MEuro IP Media Servers 55
Meuro Softswitches 340
MEuro Application Servers 370 MEuro Media
GW Controllers 230 Meuro
2007 NGN MARKET 5.4 bEuro IP Media GW
1.5 bEuro IP Media Servers
170 Meuro Softswitches 1.2
bEuro Application Servers 2.3 bEuro Media
GW Controllers 210 Meuro Market Trends -
March 2004
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Softswitch market overview
World Wide softswitch market (in M)
Source Infonetics, Gartner, ABI, Yankee
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SPs are Shifting from Try NGN to Do NGN
Packet Infrastructure Migration Plans (European
Telcos)
Voice Equipment Expenditure (Europe and NA)
lt12 months
1-2 Years
2-3 Years
3 Years
150
250
120
200
90
150
60
100
30
50
0
0
Legacy Equipment
NGN Equipment
Source Infonetics, July 2004
Source The Yankee Group, December 2003
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DSL A massively growing market
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Voice is Not Dead ! ...
2004 Global Service Provider Revenues from
End-User Services (B)
Communication
Productivity
Productivity
Entertainment
Information
Information
Commerce
Commerce
Communication

• Voice 88 of consumer communication revenues

• Voice 80 of enterprise communication revenues

Source The Boston Consulting Group/Alcatel
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But Service Providers Margins are moving from
voice to new services
ServiceBundling VAS
Profit
Voice only
Time
1
2
3
4
5
6
7
8
Source Ovum
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NGN Technological Evolution and Economical
Revolution

• Definition and Architecture
• Convergence is driving the Revolution
• Market overview
• PSTN Evolution, Class 4 and Class 5 topologies
• Conclusion

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NGN - Drivers and Purposes
CAPEX/OPEX Optimization
New Revenue Generation
Bypass expensive transit resources
SS7
Data (IP or ATM)
PSTN (TDM-based)
IP
IAD
POTS/ISDN
Dial-up
POTS/ISDN
xDSL
H.323/SIP
Internet offload, PSTN replacement (Class
4/5) Competitive Voice
IP TelephonyBroadband NGN (advanced/multimedia
services)
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PSTN Evolution to NGN

• Strategic Trends
• data traffic (bandwidth) is becoming 2 to 5 times
  higher than the voice traffic.
• IP is becoming the universal transport protocol
  used by all services
• How PSTN should evolve ?
• as before, with its dedicated optimised
  technology (TDM) ?
• or move to packet IP networks, telephony being a
  service among others ?
• background reasons to evolve
• service merge and new services
• DSL access penetration
• cost of ownership one network instead of
  separated networks

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Bandwidth for VoIP

• Voice compression (handled by Gateways)
• no voice compression (packet voice remains G711
  coded)
• service transparency for fax and modem calls
• voice compression and /or silence suppression
• according to codecs, bandwidth can be divided by
  2 up to 5 and even more
• Strong impact on the bandwidth required and on
  the number and size of transmission links
• Packet headers
• short packets packet header impact
• Increase the bandwidth required typical factor
  1.6

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PSTN Evolution to NGNWhat do we observe now

• Packet technology for voice is now in place
• rapid evolution in its performance, features, and
  costs (CAPEX)
• addresses evolution to multimedia services
• However, Not yet in a large scale deployment
• focused applications (dialup offload, long
  distance bypass, voice services on top of High
  Speed Internet access Cable and DSL)
• many trials successfully run
• strategic decisions now taken by some operators
  to move their PSTN network to NGN
• General feeling / agreement that it is taking
  more time than initially expected
• for technological reasons
• for economical reasons
• why hurry to replace something that is working
  well ?!

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NGN Network Conceptfor PSTN evolution
interworking
Intelligent Network Appl. Servers
Access Gateway
Softswitch Media Gateway Controller
N7 Signalling
H.248
H.248
H.248
Access Gateway
IP/XX Network
PBX
PSTN
Trunking Gateway
H.248
Access Gateway
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NGN EconomicsNetwork evolution issues

• Network expansion
• with existing TDM technology (reference case)
• with NGN solution
• sometimes called Cap and Grow this means keeping
  the existing PSTN network as it is, and grow with
  NGN equipment
• Network replacement
• Replacement of out-phased (end of life) TDM
  equipment
• gradual replacement this means coexistence of
  the two technologies over a long period of time
• full accelerated replacement with a short
  transition period
• Network consolidation
• Cost Optimisation of the network
• Through modern technology TDM switches allowing
  fewer nodes
• network consolidation can also be made now with
  NGN solutions
• consolidation can be coupled with replacement

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PSTN Evolution cases

• NGN CLASS 4 (transit level)
• concerns only the evolution of the transit
  network to NGN
• transit exchanges (TEX) are replaced/migrated to
  NGN
• existing local exchanges (LEX) supporting
  subscribers remain untouched (kept in TDM
  technology)
• can be understood as a partial evolution
• NGN CLASS 5 (local level)
• local exchanges (LEX) are replaced/migrated to
  NGN
• this case implies also a Class 4 NGN part

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Network Architecture TDM reference case
General Architecture
NATIONAL LEVEL
Transit Network
Highly Meshed network
REGIONAL LAYER
TDM trunks (E1s)
REGIONAL LEVEL
Local Exchanges
LEX LEVEL
Remote Units
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NGN Class 4 Network architecture
Softwitches /MGCs in a few sites
NATIONAL LEVEL
Packet network usually built withan edge layer
and a core layer
Trunking gateway in each regional sites
Packet network
REGIONAL LEVEL
IP links
IP links
2 types of topology
Local Exchanges
LEX LEVEL
Remote Units
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NGN Class 4 topologies

• Trunk Gateways deployment possibilities
• In each regional transit site or in an optimal
  number of sites with direct connection of LEX
  through TDM links
• Enable network consolidation reduce number of
  transit sites and benefit from high density
  gateway port equipment.
• Compromise with transmission costs
• On top of regional Transit exchanges
• handling national transit
• In each local site on top of the LEX
• implies rather a small size Trunk gateways (E1
  instead of STM1 in major cases)

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NGN Class 5 case network architecture
PSTN
NATIONAL LAYER
Softwitches/MGCs located in a few sites
Transit Network
Trunking Gateway
REGIONAL LAYER
H.248
PACKET
or
NETWORK
LEX LAYER
H.248
AGW (centralized)
Remote Units
AGW (distributed)
AGW - Access GateWay
TGW - Trunking GateWay
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NGN Class 5 topologies

• Access gateways alternatives
• Distributed
• Multiservice access systems with integrated
  gateway functionality
• Traditional access system remote access
  gateways
• Centralized
• Traditional access systems Centralized access
  gateways

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NGN Class 5 application cases

• Replacement of out-phased LEX
• LEX replaced by access systems with access
  gateways.
• Creation of NGN class 5 islands within the TDM
  network
• Islands interconnected through the packet network
• Trunk gateways for interconnection with the TDM
  network parts
• NGN growth over time, and gradually replacing
  existing LEX when reaching end of life

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NGN Class 5 application cases

• Cap and grow case
• access systems with access gateways are
  introduced for new subscribers besides the
  existing LEX
• an overlay NGN class 5 within the TDM network
• Trunk gateways for interconnection with the TDM
  network parts
• NGN growth over time, and further replacement of
  existing LEX when reaching end of life

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NGN Class 5. Cap Grow
Softwitches located in a few sites
Trunking gateway
Packet network
TEXLAYER
IP links
Trunking gateway
Access gateway
Access gateway
LEX LAYER
Exchange A subscriber Growth
Exchange A
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Softswitch/MGC implementation

• Media Gateway Control (MGC) function can be
  implemented
• On a new stand alone equipment (Softswitch)
• Or on an existing TDM switch (MGC)
• which simultaneously manage TDM
  traffic/subscribers and NGN traffic/subscribers
• allows feature parity and service homogeneity
  between TDM part and NGN part of the network
• bring migration flexibility by its hybrid TDM/NGN
  characteristics

43

NGN Class 5. Cap Grow
Trunking gateway
Packet network
Trunking gateway
TEXLAYER
IP links
Access gateway
Access gateway
MGC function added on a few existing TDM switches
MGC
LEX LAYER
Exchange A subscriber Growth
Exchange A
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NGN Technological Evolution and Economical
Revolution

• Definition and Architecture
• Convergence is driving the Revolution
• Market overview
• PSTN Evolution, Class 4 and Class 5 topologies
• Conclusion

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PSTN evolution to NGNEconomic analysis

• PSTN evolution
• all network layers /levels impacted by new
  network architecture
• packet technology not only applies to Internet
  services but also to traditional voice services
• NGN and TDM network have to co-exist and
  inter-work
• large variety of operator cases
• rapid technology evolution CAPEX impact
• OPEX impact (network simplification,
  consolidation)
• transmission saving and transportation synergy
  aspects
• Modeling tools exist and are taking all these
  parameters into account. They require precise
  network information to effectively compare
  solutions

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PSTN migration to NGNSome conclusions

• Conclusion may vary from one case to another,
  however some generic results have been found
• NGN technology for narrowband voice access
  usually involves a slightly lower Capex than
  using TDM for the same service
• NGN technology leads to significantly lower Opex
  compared to existing TDM (specifically if the
  network was not already consolidated with a fewer
  number of exchanges)
• Use by a network operator of a common IP backbone
  is a strong driver for NGN class 4 applications
• The case of Class 5 replacement is usually less
  attractive, except in case of strong growth (Cap
  and Grow) or in case of obsolescence and absolute
  need to replace
• For most operators the priority today is in
  broadband access and development of new services
  see next slide

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NGN Introduction ScenariosChanging priorities
Services First
Network First

• Business
• impact

• Business
• impact

New services
New services

• C5 TDM
• optimization

• C5 TDM
• optimization

• Voice
• Trunking

• Voice
• Trunking

• Services launched

• Services launched

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Economical revolution

• Similar to the technological evolution from
  Analog to Digital 20 years ago, NGN applies to
  traditional voice services
• But
• The actual revolution is in the booming of
  broadband access, the proliferation of new
  services including various voice application
• This what we will work out in next chapter