TDM Services

TDM Product Roadmap Update

This statement has been written in response to customer enquiries about BT’s plans for its retail TDM services, and supersedes all previous updates, the last of which was published in November 2012.

BT has a well established portfolio of retail Time Division Multiplexed (TDM)1 private circuit services, and understands that over the years customers have come to rely on the stability and high performance characteristics of the services provided by these products.

However it is also clear that market demand for these services has been declining for some time now as technologies and the requirements of our customers’ naturally evolve. Six years ago we undertook both a technical review of the network to assess its sustainability and a commercial assessment of the viability given the projected demand profiles of the time. From this we published a roadmap of the future of the TDM portfolio where the withdrawal of most of the products was planned for 31st March 2018. We have now repeated this exercise and, together with feedback from customers on our original timescales, examined again the expected future demand profile and technical view of the platform to assess the scope for a short extension to the life of these products.

As a result, BT has concluded that a process of network compaction intended to release additional spare equipment capacity for maintenance re-use, will now enable us to continue to support almost all of these products on existing platforms for a further two years i.e. until the 31st March 2020, at which point they, unless otherwise stated in the product specific sections below, will be fully withdrawn from service – i.e. they will cease to be operational after this time.

We intend to withdraw all remaining currently available retail analogue and KiloStream products as detailed in the sections below from new supply effective 1st September 2016. This is known as the stop sell new (SSN) date and means it will no longer be possible to order new circuits of these types or re-site existing services. We gave notice to this effect via the BT Price List on 1st August 2014.2

Existing product definitions and performance characteristics will remain largely unchanged.

It is important to note however that whilst we are able to delay the final withdrawal of services for a further two years, thus giving customers a little more time to complete migration plans, the position with the transmission platform is much as it was before – it continues to age and will become increasingly challenging to support. We anticipate that beyond March 2018 there will be potential for a slight but progressively increasing risk of impairment to current Service Level Agreement (SLA) performance, and we recommend customers recognise and allow for this when planning their migration strategy and approach, thus minimising any impact on, or potential risk to, their normal business operations. Hence whilst we currently have no plans to modify the SLA’s on these products after March 2018 we will review them from time to time to assess whether they remain appropriate and achievable. We will notify planned changes no less than one year in advance via the BT price list.


Retail Digital Services 1Mb and above (BT MegaStream)


BT has previously withdrawn the following products, and any associated commercial variants from new supply, also known as stop sell new (or SSN).

  • MegaStream 1, 8 and 622
  • MegaStream Directly Cabled
  • Prime MegaStream variants

This means it’s no longer possible to order new circuits of these types or re-site existing services.

BT will, however, continue to maintain any existing circuits until these products are fully withdrawn from service. For MegaStream 1 we originally stated we expected full withdrawal to be around, but no earlier than, December 2014. However this has proved to be both undesirable for our customers and impractical for BT, so full withdrawal of MegaStream 1 will now be aligned with the rest of the sub 2Mb portfolio – i.e. 31st March 2020.

We intend to withdraw the LearningStream product, and any associated commercial variants from new supply (known as the stop sell new or SSN date) on 1st September 2016.

We will continue to support all other existing MegaStream products nationally, (at and above 2Mb) as long as demand exists, and subject to the availability of the relevant Partial Private Circuits (PPC) until at least March 2020, i.e. there is currently no planned withdrawal date for these services

Retail Sub 2Mb Digital Services (BT KiloStream and KiloStream N)


BT has now withdrawn the following products, and any associated commercial variants from new supply, also known as stop sell new (or SSN).

  • All KiloStream products at speeds below 48Kb (i.e. 2.4Kb, 4.8Kb, 9.6Kb and 19.6Kb) thus removing the X.21bis (V.24) interface option from the KiloStream portfolio
  • All KiloStream N speeds except 128Kb, 256Kb and 512Kb (i.e. 192Kb, 320Kb, 384Kb, 448Kb, 576Kb, 640Kb, 704Kb, 768Kb, 832Kb, 896Kb, 960Kb and 1024Kb)
  • KiloStream Plus
  • DealerStream 7 – 10
  • KiloStream Assured Restore (Fully withdrawn from service)

This means it’s no longer possible to order new circuits or re-site existing services of these types. BT will, however, continue to maintain any existing circuits until these products are fully withdrawn from service. For a number of KiloStream product speeds we originally stated we expected full withdrawal to be around, but no earlier than, December 2014. However this has proved to be both undesirable for our customers and impractical for BT, so full withdrawal of all these services will now be aligned with the rest of the sub 2Mb portfolio – i.e. the 31st March 2020.

We intend to withdraw all remaining KiloStream (48Kb and 64Kb) and KiloStream N products (128Kb, 256Kb and 512Kb), and any associated commercial variants from new supply (known as the stop sell new or SSN date) on 1st September 2016.

In addition it will no longer be possible to order new diversity products linked to, or associated with, existing KiloStream or KiloStream N services after 1st September 2016.
We will continue to support all remaining KiloStream and KiloStream N services (including current aggregated bearer variants) as long as demand exists, and subject to the availability of the relevant Partial Private Circuit products (PPCs) until 31st March 2020 when they will be fully withdrawn from service. Services will continue to be provided on the existing access and transmission platforms ensuring performance characteristics will remain largely unchanged.
BT is not currently planning to develop directly equivalent 21CN replacement services to replace sub 2Mb digital private circuits as there are already other business connectivity services available including Ethernet and IP Connect, optical, machine to machine (M2M) and business broadband services.

National Analogue Services


We will continue to support existing national analogue point to point and point to multi-point products, as long as demand exists and subject to the availability of the relevant BT copper access circuits where required, until 31st March 2020. For the avoidance of doubt this means the currently available active (or amplified) point to point products;

  • Analogue Standard {EPS 1 & 21} and similar product variants,
  • Analogue Premier {EPS 25B} and similar product variants,
  • Analogue Network {EPS 3N} and similar product variants,
  • Analogue half circuits to Other Admins (OA’s) where still available, and subject to the continued availability of corresponding half circuit products in the OA’s

The multi-terminal products,

  • Analogue Multipoint {EPS 42 & 51},
  • Analogue Omnibus {EPS 61 & 72},

as well as any obsolescent equivalent services that have been previously withdrawn from new supply.

Power feeding and line isolation facilities will also continue to be available for these services where required. Services will continue to be provided on the existing access and transmission platforms, therefore minimising service disruption, performance uncertainty and reactive migration planning.
We will continue to support analogue DealerStream (1-6) as long as demand exists and subject to the availability of the relevant BT copper access circuits where required, until 31st March 2018 only.

We intend to withdraw all remaining currently available indirectly wired analogue products (i.e. those wired via a BT exchange) and any associated commercial variants from new supply (known as the stop sell new or SSN date) on 1st September 2016.
In addition it will no longer be possible to order new diversity products linked to, or associated with, existing analogue private circuit services after 1st September 2016.

BT is not currently planning to develop directly equivalent 21CN replacement services to replace analogue private circuits as there are already other business connectivity services available including Ethernet and IP Connect, optical, machine to machine (M2M), IP voice and business broadband services.

Own Exchange Analogue Services


We intend to align the withdrawal timeframes of analogue private circuits that have both ends served from the same local exchange (own exchange circuits) with those of the national analogue services described above. Thus we will continue to support these services as long as demand exists and subject to the availability of the relevant BT copper access circuits where required, until 31st March 2020. This includes both baseband services (indirectly wired EPS 8 & 9 services) and active (or amplified) products (analogue standard {EPS 1 & 21}, analogue premier {EPS 25B} and analogue network {EPS 3N} products). BT will also continue to provide power feed and line isolation facilities on these services where required.

We intend to withdraw all remaining currently available indirectly wired analogue products (i.e. those wired via a BT exchange) and any associated commercial variants from new supply (known as the stop sell new or SSN date) on 1st September 2016.

In addition it will no longer be possible to order new diversity products linked to, or associated with, existing analogue private circuit services after 1st September 2016.

BT is not currently planning to develop directly equivalent 21CN replacement services to replace analogue private circuits as there are already other business connectivity services available including Ethernet and IP Connect, optical, machine to machine (M2M), IP voice and business broadband services.

Other BT Private Circuit Services


BT has already closed the CitySure and CircuitSure business continuity products to new customers. Existing customers though will be able to continue to reconfigure their business continuity requirements as required as long as they have continuously maintained at least one instance of either service from 3rd December 2012 until the point of order. We will continue to support existing CircuitSure business continuity, as long as demand exists until 31st March 2020, and CitySure installations as long as demand exists until 31st March 2018.

Only specific products detailed in this document should be considered within scope of this update. All other current private circuit products and services referenced without specific dates will be the subject of additional future updates as the roadmaps of these products are refined.

If you have any questions about this product update please contact your BT Account Manager.

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1 TDM, in this context, is the generic term for private circuit type services typically running over “traditional” or legacy platforms such as the Digital Private Circuit Network (DPCN) or legacy Synchronous Digital Hierarchy (SDH) platforms, and includes products such as Analogue, KiloStream, KiloStream N and MegaStream private circuits.

 

2 http://www.bt.com/pricing/notifs/01-08-2014/index.htm  

 

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