Features:


This list aims to become a complete listing of telephony features, as they are available from different service providers around the globe.

The source of information for the shown features is built from many articles, bibliography-keys are included with each feature and link to the references section.

As this page is thought to be a reference for features we ignored the fact that it is very long with respect to a complete and easy maintainable summary. Furthermore where appropriate we quoted definitions from the given sources, sometimes slightly ammended, without actually indicating the qoute.

The author is happy about any comments with respect to the completeness and to descriptions of the listed features.


The List:

Call Forwarding Busy

 
Abbreviation: CFB
Other Names:
Description:  With the Call Forwarding Busy Line feature, all calls to the subscribing line are redirected to a predetermined number when the line is busy. The subscriber pays any charges for the forwarded call from his station to the new destination. The subscriber's originating service is not affected.
Source: [GBGO98]

 Call Forwarding

 
Abbreviation: CF
Other Names:
Description:  The Call forwarding feature permits the subscriber to have incoming calls redirected to another number, no matter what the called party line status is. The user's originating service is unaffected, even for charging. 
Source: [GBGO98]

 Call Transfer

 
Abbreviation: CT
Other Names:
Description:  Call Transfer allows the subscriber to transfer the current call to a 3rd Party. That is, while being in a call the subscriber can put the second party on hold and can setup a call to a 3rd Party. Once the subscriber goes onhook the second party of the first call and the 3rd Party are connected. This is effectively a mid-call call transfer. The feature supports both, the subscriber being the caller or callee in the first call. 
Source: [KMMR00]

Call Waiting

 
Abbreviation: CW
Other Names:
Description:  The Call waiting feature allows the subscriber to be notified that another party is trying to reach his number while her line is busy, and to accept the new call by placing the original call on hold. Subsequently, the subscriber can switch back and forth between the calls.
Source: [GBGO98]

Calling Number Delivery

 
Abbreviation: CND
Other Names:
Description:  Calling Number Delivery is a feature that allows the called telephone to receive a calling party's Directory Number (DN) and the date and time. In the on-hook state, in a real network, the delivery of this information occurs during the long silent interval between the first and second power ringing cycles.
Source: [GBGO98]

Calling Number Delivery Blocking

 
Abbreviation: CNDB
Other Names:
Description:  Usually the callers identity is available at the terminating side, for evaluation by the calle if required (e.g. CND or TCS). This feature blocks the provision of the caller's number at the terminating side.
Source: [KMMR00]

Cellular

 
Abbreviation: Cell
Other Names:
Description:  The Cellular feature bills the subscriber for air-time on a cellular phone.
Source: [GBGO98]

Charge Call

 
Abbreviation: CC
Other Names:
Description:  The Charge Call feature allows a caller to be automatically charged on a different telephone number than the calling number. The feature is invoked by dialing a code (as defined in the sequence diagram, a prefix "0" to the called telephone number. The caller is then prompted to dial the telephone number to be charged and a PIN. If the PIN is correct, the caller can proceed with the call.
Source: [GBGO98]

Freephone Billing

 
Abbreviation: FB
Other Names:
Description:  The IN Freephone feature allows the subscriber to pay for incoming calls. Call routing is normally part of this feature, but we define that in the next feature.
Source: [GBGO98]

Freephone Routing

 
Abbreviation: FR
Other Names:
Description:  The IN Freephone feature allows the subscriber to redirect a call to various telephones, potentially using the all or part of calling number and/or the time of day.
Source: [GBGO98]

 Group Ringing

 
Abbreviation: GR
Other Names:
Description:  This feature allows for an incoming call to ring at three phones. The phone which goes offhook first is connected to the calling party. The remaining two phones stop ringing. 
Source: [KMMR00]

Return Call

 
Abbreviation: RC
Other Names:
Description:  The Return Call feature allows a caller to return an unanswered incoming call. After the incoming call, the subscriber dials *69. If the (original) calling party is busy, the feature remains active and retries until the calling party is alerted. Once the (original) calling party is successfully alerted, the feature is deactivated whether the call is completed or not.
Source: [GBGO98]

Ringback when Free

 
Abbreviation: RB
Other Names:
Description:  When a call attempt is made to a busy line with this feature subscribed, the caller is informed that she/he will be called back, as soon as the other person becomes available. Once the subscriber terminates her/his current call a connection to the stored number(s) will be established.
Source: [KMMR00]

Split Billing

 
Abbreviation: SB
Other Names:
Description:  Split Billing allows to share costs between the partners in a call. A company might provide local call charge lines to customers as a service, in which case the customer (and originator of a call) pays the local charges and the company the rest.
Source: [KMMR00]

TeenLine

 
Abbreviation: TL
Other Names:
Description:  Teen Line restricts outgoing calls based on the time of day (i.e., hours when homework should be the primary activity). This can be overridden on a per-call basis by anyone with the proper identity code. We describe this as an IN feature.
Source: [GBGO98]

Terminating Call Screening

 
Abbreviation: TCS
Other Names:
Description:  Terminating call screening restricts incoming calls. Calls from lines that appear on a screening list are redirected to a vague but polite message.
Source: [GBGO98]

Three-Way Calling

 
Abbreviation: TWC
Other Names:
Description:  Three-way calling allows the connection of three parties in a single conversation.
Source: [GBGO98]

Voice Mail

 
Abbreviation: VM
Other Names:
Description:  Voice mail works similar to an answering machine, by offering the possibility to leave a message if the caller is not answering. The stored message can be listened to by the subscriber.
Source: [KMMR00]


References:

[GBGO98] Nacy Grifith, Ralph Blumenthal, Jean-Charles Gregoire,Tadashi Ohta. Feature Interaction Detection Contest. in K. Kimbler and L. G. Bouma. Feature Interactions in Telecommunications and Software Systems V. IOS Press 1998.
[KMMR00] M. Kolberg, E. Magill, D. Marples and S. Reiff. Second Feature Interaction Detection Contest. in M. Calder and E. Magill. Feature Interactions in Telecommunications and Software Systems VI. IOS Press 2000.

Created: 23-November-1998, Last updated: 25-August-2000