With effect from 1st September 2016 all circuit diversity services to Analogue, KiloStream and KiloStream N will no longer be available for new supply.

Private Services Circuit Diversity services are available for the following circuit types: Analogue circuits which are delivered Analogue Over Digital (AOD), KiloStream, KiloStream N, MegaStream 1 & 2, (excluding Genus) and DealerStream 1 - 11 portfolio of products. KiloLine, KiloLine N and MegaLine.

Circuit Diversity will only be available for the BT portion of the circuit. Circuit Diversity is designed to provide Customers with an enhanced level of resilience over and above that already offered in standard products. Circuit Diversity is available between any of the BT Retail circuits listed above nationally.

The levels of Circuit Diversity available are:

Full End to Circuit Diversity - A single circuit or a pair of circuits will be designed such that no single cable, equipment, or nodal failure, in the BT Network between the Customer Premises, will cause total failure of the circuit or pair of circuits. Common duct infrastructure may be shared between serving nodes and cables. This level of resilience does not include assurance against any failure of duct infrastructure including local access to the Customer Premises.

Full End to Circuit Diversity is only available if the Customer has dual access into their Premises. If a second access is required and is not in existence, then the Customer will be advised. This option is only available subject to survey. Charges for the provision of additional ducts (if required) are outlined in Alternative Routeing - Charges for Infrastructure, New Analogue and KiloStream circuits and MegaStream Charges, Ancillary Charges.

Main Link Circuit Diversity - A pair of circuits will be designed such that no single cable, equipment, or nodal failure, in the BT Network between the serving exchanges will cause total failure of the circuits. Cables may share common duct infrastructure.

Basic Diversity - A pair of circuits will be designed such that no single cable failure in the BT Network between the Customer Premises, will cause total failure of the circuit or pair of circuits. Cables may share common duct infrastructure or common nodes between customer sites.

Basic Diversity is the lowest level of resilience offered. If BT Core Network is not available to support Basic Diversity then the customer will be informed that this product cannot be supplied.

Multiple Circuit Diversity - This is a further enhancement to the Circuit Diversity product that allows the enhanced levels of resilience above to be applied to a group of more than two circuits. This may be many to many or one to many and may include any mix of the above services.

Multiple Full End to End Circuit Diversity is only available if the Customer has at least two different access into their Premises. If more than one access into a Premises is not in existence, then ancillary charges will be raised for the provision of additional access. This level of resilience to achieve Multiple Full End to End Circuit Diversity is subject to survey and dependent upon the availability of sufficient capacity in the structure of the BT Core Network. This is determined by use of defined rules to be applied by BT. If such capacity is not available, then Main Link Circuit Diversity will be offered to the Customer.

Multiple Main Link Circuit Diversity provides the same degree of diversity under Main Link Circuit Diversity described above but involving multiple circuits. The circuit(s) may share the same route from the local exchanges to the Customer's Premises. This level of resilience is only available subject to survey. A number of different options are available, depending on the criticality of circuits and the availability of the different routes in BT's Core Network. All variants of Multiple Circuit Diversity are subject to the same monitoring charges applied on a per circuit basis.