The Transferred Account Procedure (TAP) is the mechanism by which operators exchange
roaming billing information. This is how roaming partners are able to bill each other for the
use of networks and services through a standard process.
• GSM Association-defined protocol for interchange of
billing data between different network operators
• Initially defined by the Transferred Account Data
Interchange Group (TADIG) in 1989.
• First TAP standard implemented in 1996
• Currently version is TAP3, launched in June 2000
• Latest update is V3.9 dated 30th November 2001
Much of the traffic carried by a GSM PLMN either originates, or terminates in another
network. The operator of the local fixed network charges the wireless operator for each call
that terminates at one of its fixed subscribers. Likewise, the GSM operator will charge the
fixed operator for each call made to a mobile number from a fixed line. Therefore GSM
network operators and their local fixed counterparts usually negotiate an interconnect
agreement to make charging as simple as possible. Other fixed international operators have
normally already negotiated similar agreements amongst themselves.
Therefore, in order to place a call from a German PLMN to a Canadian fixed phone, it is not
necessary for the German PLMN operator to negotiate a price with a Canadian fixed network
operator. The German PLMN operator negotiates a price with the German fixed network
operator.
The German fixed network operator then negotiates a price with the Canadian fixed network
operator. So, the German fixed network operator passes this call cost back to the German
PLMN. This means that the German PLMN has to recoup the cost of the call from its
subscribers either directly (retail billing), or via the appropriate Service Provider (wholesale
billing).
This form of accounting covers the division of revenue between both fixed and mobile
networks. However, it does not cover the costs incurred by foreign subscribers whilst
roaming in other networks. Consider the case of a French subscriber calling a Canadian fixed
phone from within a German network. The German fixed network will still charge the
German PLMN for the leg of the call placed to the Canadian number. In this case, the
German PLMN does not receive any revenue from its own subscriber. In order to recoup the
costs incurred by the call, the German PLMN must charge the home mobile network operator,
here the French PLMN, to cover the costs incurred by the French mobile subscriber.
It is this type of inter-PLMN accounting for which TAP was designed. The details of the calls
made by a subscriber roaming in a visited network (VPLMN) are recorded by the serving
MSC. Each call produces one or more Call Detail Records (CDRs). Although ETSI provides a
standard CDR format (GSM-12.05) many switch vendors use proprietary formats.
The CDRs produced by the MSC are transferred on a regular basis to the billing system of the
VPLMN for pricing or rating. Those call records produced on behalf of roaming subscribers,
will be converted and grouped in files under the TAP format.
The TAP files are generated and sent, at the latest, 36 hours from call end time. This means
that operators can send 1 or many TAP files per day. TAP files contain rated call information
according to the operator's Inter Operator Tariff (IOT), plus any bilaterally agreed
arrangements or discounting schemes.
The transfer of TAP records between the visited and the home mobile networks may be
performed directly, or more commonly, via a Clearinghouse. Invoicing between the operators
then normally happens once per month.
On reception by the HPLMN, the TAP record is converted into an internal format and added
together with any call records produced by the subscriber whilst within the home network.
If a service provider serves the subscriber then the records will form the basis of the wholesale
billing between the HPLMN and that Service Provider. On receipt of the information from the
HPLMN, the Service Provider may re-rate the calls according to its own tariff plans and
produce an itemised bill, including call detail, for the subscriber.
roaming billing information. This is how roaming partners are able to bill each other for the
use of networks and services through a standard process.
• GSM Association-defined protocol for interchange of
billing data between different network operators
• Initially defined by the Transferred Account Data
Interchange Group (TADIG) in 1989.
• First TAP standard implemented in 1996
• Currently version is TAP3, launched in June 2000
• Latest update is V3.9 dated 30th November 2001
Much of the traffic carried by a GSM PLMN either originates, or terminates in another
network. The operator of the local fixed network charges the wireless operator for each call
that terminates at one of its fixed subscribers. Likewise, the GSM operator will charge the
fixed operator for each call made to a mobile number from a fixed line. Therefore GSM
network operators and their local fixed counterparts usually negotiate an interconnect
agreement to make charging as simple as possible. Other fixed international operators have
normally already negotiated similar agreements amongst themselves.
EXAMPLE OF USING TAPS
necessary for the German PLMN operator to negotiate a price with a Canadian fixed network
operator. The German PLMN operator negotiates a price with the German fixed network
operator.
The German fixed network operator then negotiates a price with the Canadian fixed network
operator. So, the German fixed network operator passes this call cost back to the German
PLMN. This means that the German PLMN has to recoup the cost of the call from its
subscribers either directly (retail billing), or via the appropriate Service Provider (wholesale
billing).
This form of accounting covers the division of revenue between both fixed and mobile
networks. However, it does not cover the costs incurred by foreign subscribers whilst
roaming in other networks. Consider the case of a French subscriber calling a Canadian fixed
phone from within a German network. The German fixed network will still charge the
German PLMN for the leg of the call placed to the Canadian number. In this case, the
German PLMN does not receive any revenue from its own subscriber. In order to recoup the
costs incurred by the call, the German PLMN must charge the home mobile network operator,
here the French PLMN, to cover the costs incurred by the French mobile subscriber.
It is this type of inter-PLMN accounting for which TAP was designed. The details of the calls
made by a subscriber roaming in a visited network (VPLMN) are recorded by the serving
MSC. Each call produces one or more Call Detail Records (CDRs). Although ETSI provides a
standard CDR format (GSM-12.05) many switch vendors use proprietary formats.
The CDRs produced by the MSC are transferred on a regular basis to the billing system of the
VPLMN for pricing or rating. Those call records produced on behalf of roaming subscribers,
will be converted and grouped in files under the TAP format.
The TAP files are generated and sent, at the latest, 36 hours from call end time. This means
that operators can send 1 or many TAP files per day. TAP files contain rated call information
according to the operator's Inter Operator Tariff (IOT), plus any bilaterally agreed
arrangements or discounting schemes.
The transfer of TAP records between the visited and the home mobile networks may be
performed directly, or more commonly, via a Clearinghouse. Invoicing between the operators
then normally happens once per month.
On reception by the HPLMN, the TAP record is converted into an internal format and added
together with any call records produced by the subscriber whilst within the home network.
If a service provider serves the subscriber then the records will form the basis of the wholesale
billing between the HPLMN and that Service Provider. On receipt of the information from the
HPLMN, the Service Provider may re-rate the calls according to its own tariff plans and
produce an itemised bill, including call detail, for the subscriber.
Summary
This section has covered the following billing topics:
• Billing Principles
• Description of Call Components
• Charge Advice Information (CAI)
• Advice of Charge (AoC) Calculation
• Call Detail Records (CDRs)
• The Transferred Account Procedure (TAP)
• Billing Principles
• Description of Call Components
• Charge Advice Information (CAI)
• Advice of Charge (AoC) Calculation
• Call Detail Records (CDRs)
• The Transferred Account Procedure (TAP)
No comments:
Post a Comment