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Features & benefits of ISDN30 & 30e explained | BT Business
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Features & benefits of ISDN30/30e explained

What are the Admin Provided Call Forwarding / Diversion options?

Admin Provided Call Forwarding / Call Diversion is an exchange-controlled call forwarding option. This means that it does not require special equipment.

To set up this service call ISDN30/30e Business Sales where you can specify the destination number to which you want calls to be forwarded. The service becomes active within 24 hours.

Calls can be forwarded to PSTN, ISDN2e, ISDN30/30e (speech only or 3.1Khz can be forwarded to the PSTN). After the initial diversion, a call can be forwarded repeatedly up to a total of 4 times.

The following options are available with this type of forwarding:

  • Call Forwarding / Diversion Unconditional (CFU)
    All incoming calls are immediately forwarded to the nominated destination number.

  • Call Forwarding / Diversion on No Reply (CFNR)
    The service automatically forwards all incoming calls to the nominated destination number if the customer does not answer the call within approximately 20 seconds.
  • Call Forwarding on Busy (CFB) / Call Divert on Engaged and Failure on DASS
    The service automatically forwards all incoming calls (voice and data) to the nominated number if the customer is already engaged (also if circuit fails on DASS setups). The forwarding takes place when either all channels are in use or when an individual called number is busy (CPE supplies a ‘User Determined Busy’ signal to the network).

What are the Customer Controlled Call Forwarding / Diversion options?

Customer Controlled Call Forwarding diverts calls to all numbers to a single number of your choosing. This call-forwarding option is applied by you by programming your equipment to divert the calls. This means it is exchange-independent. Contact your equipment manufacturers if you are unsure whether your equipment supports the service. To enable call forwarding on the line, ring ISDN30/30e Business Sales.

Speech only or 3.1Khz calls can be forwarded to the PSTN. After the initial diversion, a call can be forwarded repeatedly up to a total of 4 times.

The forwarded leg of the call is chargeable. The charges appear on your bill along with the subscription for the forwarding service.

The following options are available when you use this type of forwarding:

  • Call Forwarding / Diversion Unconditional (CFU)
    All incoming calls are immediately forwarded to the nominated destination number.

  • Call Forwarding / Diversion on No Reply (CFNR)
    All calls are forwarded to the nominated destination number if the call is not answered within approximately 20 seconds.
  • Call Forwarding on Busy (CFB) / Call Divert on Engaged and Failure on DASS
    All calls are forwarded to the nominated destination number if the line is engaged.

How do I view the telephone number of the person I'm talking to at all times?

This service is available on ISDN30/30e, and is known as Connected Line Identity Presentation or COLP for short on ISDN30e (ETSI), and as Terminating Line ID Display or TLID on ISDN30 (DASS). This enables you to identify the destination number to which your outbound call has been routed. This may not necessarily be the number that you first dialled.

COLP must be an ISDN30e-only call (ETSI to ETSI) and TLID must be an ISDN30-only call (DASS to DASS). You will also need to have terminal equipment that supports it. COLP will only appear to the customer when the call is connected.

I want to keep my outgoing phone number private. Can I do this?

Yes, you can request that your CLI is revealed to no-one. This service is available free of charge by adding Calling Line Identification Restriction (CLIR) to your ISDN service via ISDN30/30e Business Sales.

If you do have CLIR added to your line you can release your CLI information on a call-by-call basis by dialling ‘1470’ before the outgoing number.

Similarly, if you do not wish to have CLIR permanently added to your line, you can restrict your CLI being released on a call-by-call basis by dialling ‘141’ before the outgoing number.

I used to have Caller ID - is this service still available?

The ISDN service equivalent to Caller ID is Calling Line Identity Presentation (CLIP). This can be ordered through ISDN30/30e Business Sales. The service is reliant on your PBX/Switch supporting this function.

What are the options for call barring?

There are several types of call barring available:

  • Admin Provided Permanent Incoming Call Barring (ICB)

    This enables customers to have outgoing-only lines. All incoming calls are barred. Permanent ICB applies to both voice and data calls on all bearer services (64kbit/s unrestricted, speech, 3.1kHz audio bearer services).

    A customer making a speech or 3.1Khz audio call to a number which is an outgoing-only line will receive either an announcement stating that calls to this number are unavailable, or the ‘number unobtainable’ tone.

    A customer attempting to make a 64kbit/s unrestricted call will receive a digital message indicating that calls to this number are unavailable.

  • Admin Provided Permanent Outgoing Call Barring (OCB)
    This enables customers to have incoming-only lines. No calls can be made from lines with Permanent OCB. Permanent OCB applies to 64 kbit/s unrestricted Speech and 3.1kHz audio calls.

  • Admin Provided Selective Outgoing Call Barring (OCB)

    Selective OCB applies to 64kbit/s unrestricted, speech and 3.1Khz audio calls. It enables customers to bar certain categories of outgoing calls. These categories are:

    • All Calls (except 999 and 150, 151, 152, 154 and 0800)*
    • International and Premium Rate Services
    • All Operator Calls (except 999 and 150, 151, 152, 154 and 0800)*
    • National, International and Premium Rate Calls (except 999 and 144, 150, 151, 152, 154 and 0800)*
    • International, Operator and Premium Rate Services.
    * Indirect Access codes are not excluded from the calls barred in this option, therefore calls prefixed with an indirect access code will not connect.

Does ISDN30/30e support sub-addressing?

Yes, it does. Sub-addressing enables you to send up to 20 alphanumeric characters (with the exception of the # symbol) with the digits of the number you are dialling. Different combinations of characters can then be allocated to each device connected to the destination ISDN line. This allows you to select the destination or end point beyond that indicated by the national telephone number. This could be, for example, a device connected to a LAN, individual devices connected to an ISDN 30e line or an application on a host computer.

Please note: You must ensure that you terminal equipment is capable of sending and receiving sub addresses in order to use this service. ISDN30/30e lines can send 20 characters internationally on data calls only where the International correspondent supports the service. Sub addressing cannot be used on calls to the PSTN or on International speech calls.

Is Malicious Call Indication (MCID) available?

Yes, in certain circumstances, at customer request. This is most likely when there have been instances of malicious calls and the Police are involved.

Can I have Caller Redirect applied to my ceased ISDN30/30e circuit?

Yes. On ceased circuits Caller Redirect can be applied to:

  • Main directory number – must not be part of a DDI range
  • Single-number DDIs
  • Complete DDI ranges
  • Part of a range, as long as it is in blocks of ten DDIs – xxx0 ending xxx9

Can I have Remote Call Forwarding (RCF) applied to my ceased ISDN30/30e circuit?

Yes, RCF is available on any main number as long as it is not part of a DDI range.

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