PSTN renewal Next Generation Access and Network IMS and fixedmobile convergence - PowerPoint PPT Presentation

Title: PSTN renewal Next Generation Access and Network IMS and fixedmobile convergence


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PSTN renewalNext Generation Access and Network
IMS and fixed-mobile convergence
Jean CraveurFrance TelecomNetworks, Carriers
IT
January 2006
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Summary

• Context
• The PSTN issue
• Next Generation Access and Network
• IMS a tool fot Fixed-Mobile convergence

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Context
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IP the basic structure of new networks

• Capability of IP to transport almost all services
• VoIP, multimedia
• But need to find means to guarantee QoS and
  security
• A huge traffic increase
• Large IP networks have been deployed
• Economic interest to be shared by several
  services
• This transport network can be used to transport
  service and network control information
• Flexibility to build new services any device
  connected can act as a control point
• But major security problems remain to be solved
  any device connected can interact with network
  control and management
• Specialized networks can now migrate towards
  these shared IP networks

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An increasing access bit rate

• xDSL over copper lines
• Important DSL coverage announced in many
  countries
• With bit rates depending on copper line length
• In France more than 95 of the lines are 512/128
  kbit/s capable
• Allowing multi-service access
• Coexistence of several services on the same
  access
• Data, video, voice (fixed or mobile)
• Based on IP connectivity
• Access traffic increase is a general trend
• ADSL2, then VDSL, VDSL2, and FTTx
• The copper line is no longer a bottleneck to
  service evolution

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Technical access evolution

• DSLAM evolutions
• From ATM based core architecture to Ethernet
• Implementation of IP layer 3 functions (CoS)
• Optical accesses
• Point to Point or PON architecture
• Telephony analog interface including VoIP gateway
  function
• Connection to DSLAM a move towards Ethernet
• To face economically increasing bandwidth needs
  (vidéo)
• Consistent with structural DSLAMs core evolution
  of the
• this is an important evolution to be well managed
  in aggregation networks
• DSLAM becomes the Multi-service Connecting Unit
  based on Ethernet

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Multiservice Multi-VC Architecture
Internet
Service Plat-forms
VC Best Effort
Network Termination
Video Service Plat-form
STB
VoD Server
VC QoS
Digital TV Network Access
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The PSTN renewal issue
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Voice traffic and technology evolution

• Rapid modification in traffic volumes
• PSTN traffic decreases significantly
• Originating PSTN voice traffic is decreasing
• Traffic transferred to mobiles and VoIP, but PSTN
  traffic decrease slowdown in 2005 due to
  unlimited offers over PSTN
• Internet switched access is decreasing (-46
  2005/ 2003)
• Traffic transferred to Broadband access
• Mobile traffic mobile is increasing (9.3 March
  2005/March 2004)
• VoIP traffic is increasing (end 2005 around 10
  of the Fixed traffic, 13 for Mass Market)
• The overall voice traffic is increasing (fixed
  mobile) (around 7, 5,2 for Fixed traffic
  including VoIP)
• A strong technological mutation
• Fast deployment of broadband DSL access combined
  with LLU fast growth
• Appearance of significant competitive VoIP offers
• Accelerating voice PSTN originated traffic
  decrease
• FT VoIP service started combined with Internet
  access
• As a second line service
• First line services with full unbundling take off
• Solutions for fixed access used by GSM networks
• UMA,

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Some uncertainties remain

• The content of Voice Services is uncertain
• Present VoIP offers can modify significatively
  the vocal usage and therefore the PSTN use and
  economy
• Present VoIP offers are in general
• Limited in terms of services
• With QoS still lower than PSTN (service
  availability)
• Enhanced voice offers with native IP terminals
  are going to happen with for instance videophony
• Will a place remain for service on analog lines ?
• A non yet stabilized technical context
• Fixed Mobile convergence perspectives with the
  NGN/IMS

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Impact on PSTN

• Traffic decrease on PSTN
• Evolution managed by reducing the number of
  switches (transit and local)
• A part of FT TDM switches reaching the end of
  their life span
• Second generation of TDM switches (2G) installed
  on early 80s
• More than half of 2G subscribers switches are 20
  years old or more
• 2G Subscribers units design second half of the
  70s
• More than 10 millions subscriber equipments
• Thousands of subscribers units
• Traffic decrease (if confirmed) may reduces the
  need for PSTN equipment replacement
• VoIP infrastructure is an alternative to PSTN
• Need for evolving PSTN service to enhanced
  services
• Convergent fixed mobile offers
• More sophisticated voice offers, multimedia
  offers
• A new generation VoIP infrastructure needed

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Possible scenarios

• Migration towards VoIP gives room in 3G circuit
  switches
• Two possible solutions (which can be combined)
• Transfer of analog lines to 3G switches to remove
  2G switches
• Migration of analog lines on POTs accesses in
  DSLAMs
• In this 2nd case necessity
• Not to have major functional service regression
• To have a transparent migration concerning all
  the phone equipments at subscribers premises
• To ensure the same availability and quality of
  service as before
• DSLAM becomes the central element for future
  voice offers
• For VoIP (use of ADSL)
• To connect remaining PSTN lines

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Which technology for conversational services?

• Main requirements
• Get an architecture open to future multimedia
  services
• Base the architecture on IP connectivity
• Provide a control architecture able to offer
  other services
• External application servers capability
• Nomadism capability embedded
• Get a robust architecture against voice future
  uncertainty
• A unique way to transfer voice in the core
  network
• VoIP seems to be the solution
• A common access network for all conversational
  traffic
• DSLAM as a universal connecting unit
• Take benefit from being an integrated operator
• Share technologies between fixed and mobile
• Take benefit from IMS definition from the mobile
  side

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Next Generation Access and Network
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Our vision One IT Network
Shared Information System
Service Platforms
Control Layer
Gigabit Ethernet
IP / MPLS Backbone
Transmission
Aggregation
Customer Access Network
Core/Backbone networks
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Evolution in access networks
Copper
New DSLAM generations
Fixed-Mob. convergence
Automatic MDFs
Optical Fibre
Aggregation node

• New Fixed and Mobile technologies enable
  increased bit rates, better cost efficiency,
  better quality and convergent services

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Broadband everywhere
Rate (bps)
Fiber (FTTx) 10 to 100 Mbps gt 100Mbps
Wireless Local Loop 1 to 60 Mbps
VDSL 20 to 50 Mbps
Wifi 11 to 54 Mbps
ADSL 2 10 to 25 Mbps
HSDPA 14 Mbps
ADSL 0.5 to 8 Mbps
Cable modem 1 to 4 Mbps
UMTS 1 to 3 Mbps
ISDN 64-128 kbps
EDGE 200 kbps
PSTN 56 kbps
In mobility
GPRS 50 kbps
Fixed usage
2003
2005
2007
2000
Source Idate
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NG broadband access strategy

• Increase service reach with higher bandwidth
• To answer the demand of migration to higher
  bandwidth
• To expand video services area
• Increase DSLAM backhaul bandwidth
• To face a growing number of broadcast video
  programs
• Evolution from ATM to GE on all DSLAM providing
  video services
• More bandwidth
• Cost reduction
• DSLAM as a multi-service connecting unit
• Subscriber fibre connection to DSLAM under trial
• Interest in POTS service provided through DSLAM

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Residential access beyond ADSL

• What technology beyond ADSL2?
• VDSL, VDSL2 in street cabinets up to 20 Mbit/s
• FTTx more than 20 Mbit/s
• Much more costly than ADSL
• For which new family of services? HD video
  services?
• A number of trials
• VDSL trials on residential market
• To enhance video services coverage
• In Paris suburbs where copper lines are too long
• B-PON experimentations
• Starting with B-PON then evolving to G-PON
• FT strategy

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Optical entreprise access

• At present,
• Data, leased lines, voice on the same fiber loop
• Optical loop deployment on enterprises
• Nearly 10,000 Large Corporate fibre connections
• GEth MAN infrastructures
• Deployed In 15 of the largest cities
• Access up to 1 Gbit/s for main enterprise sites
• Providing a layer 2 service with QoS guarantee
• B-PON trials conducted
• To serve business locations (10-30 Mbit/s
  bandwidth need)

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Evolution in aggregation and backbone networks

• Security, end-to-end Quality of Service
• IP V6
• SIP

Backbone
Aggregation

• Universal Access Node (e.g. enhanced DSLAM)

• Giga Ethernet
• Use for UMTS access

• MPLS
• Gigarouters

• Fibre bit rate increased with DWDM
• Automatically Switched Optical Network (ASON)
• Multi Service Provisioning Platform (MSPP)

Transmission
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NG Network implementation has started in 2004

• What it is
• NGN (Next Generation Network) allows separation
  between transport and control layers for network
  and services
• The benefit is cost reduction
• Common IP backbone network, GigaEthernet and ATM
  aggregation networks and enhanced multiservices
  DSLAMs
• Currently underway
• FT currently operates a VoIP /ToIP and visiophony
  infrastructure for Enterprise and Residential
  markets in France
• Residential VoIP service opened in 2004
• 484,000 VoIP residential customers end of
  September 2005
• Access to Service Platforms is today through H323
  protocol, and is planned in 2006 to migrate to
  Session Initiation Protocol (SIP)
• Complying with new industry standards in view of
  future multimedia services beyond pure voice

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NGN and Triple play offers
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IMS and fixed-mobile convergence
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Why an IMS based control architecture?

• Take benefit of the 3GPP definition work
• System oriented to SIP session control
• Suitable for conversational services
• Include mobility and centralized user data
  management
• Possible synergies in product development costs
  (fixed and mobile)
• IMS architecture seems to be a good basis for
• Controlling IP phones and Residential GW through
  SIP protocol
• Controlling DSLAM VoIP gateways (PSTN simulation)
• To serve residual analog lines
• Network convergence?
• Restricted to data based applications as long as
  IMS is not controlling mobile voice
• Mobile voice control under study by 3GPP
• Nomadic services in the fixed network

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NGN with IMS implementation will start in 2007

• What it is
• IMS (IP Multimedia Subsystem) will provide common
  control layer for fixed and mobile network and
  services
• Standardized by ITU and ETSI
• The additional benefits
• Further cost reductions
• Control and transport of media flows of any
  nature and origin, including conversational flows
  
• Enabling the product factory for network-native
  convergent services (e.g. Home Zone phase 2)
• Currently underway
• Specification
• Evaluation of  Application Servers  providing
  multimedia and Fixed/Mobile service continuity to
  Enterprises

• Preparing the common multimedia broadband
  infrastructure for fixed and mobile services
  beyond pure voice

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NGN/IMS make possible convergent services
User information
Network and service control information
Application
Service Platforms
Roaming and mobility
HSS
Common control layer
Control
SIP protocol
DSLAM
Transport
Aggregation
IP/MPLS Backbone
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Main issues for VoIP/NGN networks (1)

• Define the appropriate IP layer arrangements
• Allowing smooth network management (network life)
• Addressing, security, VPN
• Specific QoS requirements for VoIP?
• Define the optimum topology
• Optimum VoIP edge function location, call servers
  centralisation?
• Impact on aggregation network
• Reach the QoS grade of present PSTN
• Reliability, network management and operation
  functions
• Control of mobile voice services through IMS
• VoIP/NGN interconnection issue a way to be
  defined
• PSTN gateways implementation short term issue
• VoIP interconnection
• To be positionned to peering IP
• Should be the target, which type of service
  contract between operators ?

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Main issues for VoIP/NGN networks (2)

• Transport /control separation
• Makes possible important voice and service
  control centralization
• Ten (s?) call server sites
• To be compared with 500 Local Circuit switches
• Voice flows handled upper in the network
• 60 à 250 sites de MAG/EDGE
• New security requirements
• Risks from Internet
• Concerning the network or the IS which is
  connected to it
• Centralization makes easier security measures
• Need to logically separate voice ?