ngn interconnect update joining the threads 25 may 2005 for wg discussion on 3 june
TRANSCRIPT
NGN Interconnect Update
JOINING THE THREADS
25 May 2005
FOR WG DISCUSSION ON 3 JUNE
INTERCONNECTION TODAY
• Distance and Element Based
• Voice Stovepiped (snapshot below, as example)
• NNIs for Frame and ATM
• Partial Private Circuits using PDH/SDH
Site Type “Ex-DLE RCU” “DLE” “Tandem” “NGS”
# Sites N/A 213 62
# Sites w/ ISI 32 82 6 56
ISI E1 Volumes:
- 2,449 1,598 54,455
IEC E1 Volumes:
1,686 2,163 353 19,616
NGN INTERCONNECT
• Converged Point of Handover Multi-service pipe between two operators
Architecture (i.e. standards) to be agreed at TSG
In 21CN, BT side will generally be at a fibre MSAN
• Service Specific Conveyance Multiple services will be conveyed across a PoH
Some will be price controlled (e.g. PSTN), others won’t
Some will require service specific network elements
Some services can be defined today, others can’t
For discussion purposes.No implementation assurances
CONVERGED POINT OF HANDOVER
• Convergence requires a glue layer Long term vision is native Ethernet, but
Some services may still require SDH
And most UK networks are SDH based
• BT Proposal to NICC/TSG Hybrid: SDH, Physical Ethernet and/or Ethernet VLANs
Provides implementation flexibility
Allowing for technology evolution
But defines Ethernet VLANs as the glue layer
For discussion purposes.No implementation assurances
GigE Physical
IP
SDH Physical VCAT
ATM
AT
M B
ackh
aul S
ervi
ces
GFP
Ethernet VLAN
IPIPIP IP
VCAT
ATMGFP
Ethernet VLAN
IPIPIP
PS
TN
/ISD
N S
ervi
ces
Oth
er S
ervi
ces
on I
P
TD
M S
ervi
ces
PS
TN
/ISD
N S
ervi
ces
Oth
er S
ervi
ces
on I
P
AT
M B
ackh
aul S
ervi
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TD
M S
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DAY ONE PoH ARCHITECTURE
For discussion purposes.No implementation assurances
HOW DEEP SHOULD PoH BE?
• BT proposed PoH at ~130 Metro node sites
• Some Operators want deeper PoH, because: They have existing fibre assets that may be stranded
They want to leverage LLU investments
They want to intermediate the wholesale market
They believe conveyance will be cheaper
• Ofcom wants deeper PoH, because: Policy of promoting infrastructure build
Greater competition for backhaul
For discussion purposes.No implementation assurances
POTENTIAL HANDOVER POINTS
For discussion purposes.No implementation assurances
Metro Node Metro Node
Tier 1 MSAN Node
MSAN Node
CMSAN
FMSAN
TAM
Legacy
MSAN Node
CMSAN
FMSAN
TAM
Legacy
MSAN Node
CMSAN
FMSAN
TAM
Legacy
CMSANTAM
Legacy
MSAN Node
~130 Sites
~1500 Sites
~4500 Sites
~5500 Sites
PRouter
COREDWDM
4/4/3SDXC
Core Node
~10 Sites
~
Voice/PCPE
PRouter
COREDWDM
4/4/3SDXC
Legacy switch
functions
Voice
Intra Metro Ethernet Network
EdgeWDM Ethernet
PE
BRAS
CMSAN
EdgeWDM
FMSAN
TAM
Legacy
~
Voice/PCPE
PRouter
COREDWDM
4/4/3SDXC
Legacy switch
functions
Voice
Intra Metro Ethernet Network
EdgeWDM Ethernet
PE
BRAS
Tier 1 MSAN Node
CMSANEdgeWDM
FMSAN
TAM
Legacy
CMSANTAM
Legacy
CURRENT BT THINKING ON PoH
• Converged PoH as a new NGN product
Independent of service-specific conveyance riding on top of PoH
Dimensioning starting at STM-1 for SDH or Gig-E
Monthly port-based pricing with distance chargeif circuit leased from BT
• Handover Points
Tier 1 MSANs co-located at Metro nodes
For operators with existing fibre, PoH at customer side of nearest Tier 1 MSAN
For LLU operators, PoH at nearest Tier 1 MSANFor discussion purposes.No implementation assurances
SERVICE LEVEL CONVEYANCE
• Multiple services will co-exist on PoH Services may require specific network elements
Commercials will be different for different services
• Highest priority is PSTN replication Needs both media routing and session control
Pricing will be determined by regulator
• Industry innovation will require new services E.g. Multimedia, circuit emulation & bitstream evolution
For some, pricing will be commercially negotiated
For discussion purposes.No implementation assurances
SERVICE CONVEYANCE PROTOCOLS
SIP-I
RTP
SIP
RTP
PNNI
SCTP
UDP
SCTP
UDP
ATM over Ethernet
Circuit Emulation
Ethernet Glue Layer
Point of Handover
C7 PSTN REPLICATION MULTIMEDIA ATM NGN PPC
For discussion purposes.No implementation assurances
Note: ATM and Circuit Emulation over Ethernet subject to further standards work.
STANDARDS CHALLENGES
• Many fora developing open standards
• BT committed to NICC/TSG process
• Sourcing standards for consideration from:
IETF, TISPAN, Metro Ethernet Forum, 3GPP, etc.
• But, localised variants cost time and money
Balance between backward compatibilityand the burden of forever carrying the past
For discussion purposes.No implementation assurances
SIP-I CONDUNDRUM AS EXAMPLE
• ITU ratified Q1912.5 for Global ISUP in SIP
• ETSI Plenary in September; expected to have ratified European normalised standard in December.
• UK NICC must agree and ratify the UK specific variations and options to ETSI SIP-I
• Vendors will need to support multiple SIP-I variants on a global basis:
• Will we back to the IUP problem in N years?
For discussion purposes.No implementation assurances
CURRENT BT THINKING ON NGN NARROWBAND CALL CONTROL
• Altnet ability for full call control of their customer’s individual baseband voice line from their call server
• Altnet assumption was that this required physical interconnect to MSAN line card H.248 gateway
• Mutual learning from Consult21 Engagement
• Proposed BT solution enables NGN CPS and WLR for all wholesale customers
Provides full call control to those who invest in Call Servers
Not limited to deep infrastructure players
Promotes competition and innovative feature discrimination
For discussion purposes.No implementation assurances
ILLUSTRATION OF AGCF SOLUTION
MSAN MSAN
H.248control of line card
ALTNET 1ALTNET 1BTBT
ALTNET 2ALTNET 2Call
Server
AGCF“H.248 Proxy”
AGCF“H.248 Proxy”
SIP
EquivalenceDemarcation
SIP
CallServer
CallServer
SIP-I
For discussion purposes.No implementation assurances
CURRENT BT THINKING ON 21CN NARROWBAND CONVEYANCE
• Ofcom will determine PSTN conveyance rates
“Technology Neutral” NCC currently in consultation
Market review will follow to set 21CN specific conveyance rates
• Industry needs commercial certainty during 4 year interregnum when 2 PSTN networks overlap
Non-congruent PSTN conveyance rates will be disastrous for all
Creating new arbitrage markets; hurting sustainable competition
• New Wave voice products that do not rely on C7 and PATS will follow commercial pricing models
No SMP nor bottleneck
Where all operators will try to innovate for new revenueFor discussion purposes.
No implementation assurances