NGN Multi-Service Interconnect Link (NGN-MSIL)

Robin Charles

For discussion purposes.No implementation assurances

NGN Multi-Service Interconnect Link

• Enable CPs with similar IP based networks to interconnect with BT

• Capable of supporting multi-services over the same link

• Several Industry SoRs for NGN-MSIL have been received

BT’s21CN

CP MULTI-SERVICE INTERCONNECT LINK

For discussion purposes.No implementation assurances

NTENTE

PPC

PSTN/ISDN

Multi-Media

CP

PPC

With ISH Customer Provides

BTCSH

ISH

PSTN/ISDN

NGN Multi-Service Interconnect Link

NGN Multi-Service Interconnect Link

TDM

Fibre (‘Fat’ Pipe)Border

Gateway

Border Gateway

Multi-Media

21CN

Border Gateway

Border Gateway

For discussion purposes.No implementation assurances

• Design based on SDH GFP , as Ethernet and MPLS standards are not mature (particularly for latency, security and OAM).

• Will have independent service-specific conveyance riding on top of Point of Handover (PoH)

• Dimensioning starting at STM-1 for SDH or Gig-E

• Option with optical transport (CWDM) with SDH and Ethernet interfaces

NGN-MSIL

For discussion purposes.No implementation assurances

• Interfaces:

• TDM - STM1, STM4 and above

• Ethernet – VLAN’s to support PSTN Voice

• Resilience options (Service to define requirements)

Scope

For discussion purposes.No implementation assurances

• An operationally well-understood and trusted technology that can support a range of services

• Provides strong trail separation via use of Virtual Containers but this does not give good granularity for bandwidth allocation per trail

• Each service can be assigned to an SDH VC. Ethernet and packet services can be supported by General Framing Procedure (GFP) in SDH. Virtual concatenation (VCAT) would be used to support services and interfaces requiring bandwidths that are multiples of the SDH V

• High cost solution

SDH

For discussion purposes.No implementation assurances

NGN-MSIL

• This is a replacement for the existing Handover.

• Link is Service independent

• VLANS will be configured for Services.

• Two options for delivery - ISI, CSI

• Standards:- SDH, Ethernet physical, Ethernet VLAN, Ethernet VLAN tag addressing.

• Need to secure separate paths per customer

• Link SLA’s for fulfilment and assurance to align to the SLA’s for the individual services carried by NGN-MSIL

For discussion purposes.No implementation assurances

NGN Interconnect Basic Diagram for PSTN/ISDN

CMSAN

Call Server

NTE

NTE

Call Server

BorderGateway

BT CP

MSIL

SIP (I) Signalling

Metro Node

BorderGateway

NTE

Fibre MultiService

Access Node

Copper Multi

Service Access Node

Multi Service Interconnect

Link

For discussion purposes.No implementation assurances

• A basic diagram (previous slide) for NGN Interconnect and aspects of the additional complexity.

• Standards – still a long way to go with many hurdles to jump

• We envisage all the major PSTN/ISDN Call Types being replicated using a G711 Codec.

• BT’s provision and repair to continue with improvements and modifications as necessary.

NGN Interconnect Call Conveyance

For discussion purposes.No implementation assurances

• Relationship between POH and Point Of Service Interconnect needs further discussion.

• The physical POH at Tier 1 MSAN for migrating existing TDM voice or Metro node site to support all services POSI.

• Connectivity required to reach from POH to POSI where POH is the MSAN site.

Voice

For discussion purposes.No implementation assurances

Transport

• Existing PPC SDH equipment does not have a GFP/SDH card.

• The Link will be transparent to the service.

• CSI the preferred delivery.

• SDH is preferred delivery for Operations

• Connectivity will be required to link POH and POSI.

• Voice services will be delay sensitive, need to comply with NICC standards.

• POH for NGN-MSIL will be Client interface on NTE.

Where optical interfaces are considered then optical drive distances will need investigating, e.g. use of 1310nm instead of 850nm to extend reach.

For discussion purposes.No implementation assurances

Process

• CP must have (or order new) NGN-MSIL prior to service

• CP can then order the Services / Interfaces required

• Rules need to be defined for Service ordering (plus additional Backhaul links)

• CP must be responsible for Capacity Management.

• Provision and management of client interface from CP NTE/NTU to BT Mux as required by the product. E.g. GE, STM1

For discussion purposes.No implementation assurances

Pricing

•For the Link , pricing expected to be connexion charges plus rental with a distance based element mapped to the PPC model.

•(Existing services conveyed over the link will map to the current billing arrangements for the respective services.)

For discussion purposes.No implementation assurances

Tactical delivery options

•PPCs continue to be supported

•Ethernet services could be delivered by WESB

-what bandwidth required?

-long term market for premium SDH/GFP bearer to carry Ethernet/IP?

•WDM with dedicated wavelengths per service possible –but not for ISH