The following charges are additional to the full connection and rental charges for standard permanent and temporary BT ISDN 30 service (see Part 24 of this Section).

This service is not available on PSTN split line voice service.

ISDN30 Alternative Routeing gives customers connection to their normal serving exchange over two different routes involving different cables and different ducts (if available) and building entry points (if available). ISDN30 Diverse Routeing gives customers connection to a second local exchange designated by BT, in addition to that used for their normal ISDN30 service. This provides two different routes involving different cables and serving exchanges and different ducts (where possible) and building entry points (if available).

Full ISDN30 connection and rental charges apply for channels which have been diversely or alternatively routed , the first 15 attracting the higher connection charge and subsequent channels attracting the lower connection charge. In addition charges are applied where new ducts or fibre are provided or special construction work is involved:

Charges for infrastructure over and above standard requirements are given in Section 45 Part These charges include work on internal trunking & traywork; breaking through walls; additional poles, ducts and cables; radio charges and miscellaneous non-standard or specially requested items.

If Diverse or Alternative routeing is subsequently provided on existing channels, then reconfiguration charges will apply.

DDI dual parenting allows DDI to continue operating in the event of a local exchange failure by connecting the customer to two local exchanges. This may be achieved either via diverse routeing or by using the normal ISDN30 route to the local exchange and re routeing half on to a second local exchange.

Full ISDN30 connection and rental charges apply for channels on each local exchange, with the first 15 on each route attracting the higher connection charge. In addition any diverse or alternative routeing charges will apply.

Site Assurance enables customers to call BT and have their calls rerouted to an alternative site within a contracted time if their normal site becomes unusable for any reason. This can be achieved by:

Option 1: use of basic call diversion to route all calls to a pre-arranged single number, or

Option 2: by setting up a group of ISDN30 channels on a standby site, solely for the receipt of diverted calls from the assured site.

In addition:

Option 1: call charges will be raised for the diverted part of each call when the diversion is activated.

Option 2: normal ISDN30 connection charges and rentals apply for the channels at the standby site and calls to these channels will be uncharged. Out of area charges will apply if the standby site is in a different local charge group.

Back in Business (BIB) provides Call Centre and/or Voicemail Service when an ISDN30 Customer experiences Service Failure of all its ISDN30 channels. This Service is available to BT ISDN30 Customers on an opt in basis, either at the same time as ordering an ISDN30 line or anytime later during the period of the Contract. At the time the Customer reports a Service Failure, BT will offer either the Call Centre option or the Voicemail Service option.

Call Centre Option - Not available for new supply with effect from 15 February 2010.

BT will divert the Customer's incoming calls to the BIB Support Centre where callers will hear a recorded announcement advising them that problems are being experienced with the dialled number. The greeting can be tailored for the Customer. The caller will then be transferred to a team of advisors who will take messages and forward details of the call to the Customer at regular intervals as agreed with the Customer, but not more frequently than every 15 minutes. The BIB Support Centre is available between 8am - 5pm Monday to Friday, excluding Bank Holidays.

Voicemail Option - The caller will be automatically diverted to a Voicemail Service, which is available 24 hours a day, 365 days a year. Messages left on the Voicemail Service can then be remotely accessed and retrieved by the Customer at its convenience. Following repair of the Service Failure, BT will subsequently remove any remaining messages from the Voicemail, upon giving notice to the Customer.

There is no Minimum Period for Back in Business.

Customers are still eligible to claim under the Customer Service Guarantee Scheme (CSGS). Under the terms of the CSGS, Call Diversion may be offered, but as an alternative to BIB.

In the event of Service Failures affecting a large number of BT Customers, BT may have difficulty meeting the exceptional high demand and as a consequence may have to temporarily withdraw the Call Centre option.

For those ISDN30 Customers who have not previously opted for BIB, BT may at its discretion make BIB available, on a case by case basis, if a Service Failure is estimated to take longer than 5 hours to repair.

(a) Additional charges apply for fibre only or fibre and duct provision.

(b) Where site assurance is applied to a group of channels in a number group, all channels in that group must be invoked together.