Technical requirements under 5 of the Telecommunications Customer Protection Ordinance

Technical requirements to be met by metering and billing systems in order to ensure accurate call price computation under 5 of the Telecommunications Customer Protection Ordinance Technical requirements under 5 of the Telecommunications Customer Protection Ordinance The technical requirements laid down in 5 of the Telecommunication Customer Protection Ordinance are to ensure minimum accuracy of metering and billing systems and hence to give customers confidence in the accuracy of the charges levied for connection-dependent telecommunications services provided for the public. 1 Scope of application These technical requirements refer to the way in which providers bill their customers for the provision of connection-dependent telecommunications services for the public. These technical requirements do not cover accounting between providers. 5 of the Telecommunication Customer Protection Ordinance deals with all time- and/or distance-sensitive calls established as part of telecommunications services for the public, regardless of the type of service provided, the bandwidth used as well as the transmission and switching technique deployed for the provision of service. Volume-sensitive telecommunications services are not covered by these technical requirements. For the purpose of illustrating these requirements, the metering and billing process is broken down into the following functions: data collection, data postprocessing and data transmission. The requirements concerning data collection refer to the accuracy with which the call data of telecommunications services for the public have to be collected (metering accuracy). In this context, a distinction is made between the accuracy of time metering and distance metering. The requirements concerning data postprocessing refer to the accuracy with which the call data collected have to be converted into charges (billing accuracy). In contrast to the requirements described herein with regard to billing accuracy within the framework of data postprocessing the quality parameter "billing accuracy" as defined in 32(1) item 9 of the Telecommunications Customer Protection Ordinance refers to the statistical collection of queried telecommunications bills. The requirements concerning data transmission refer to the degree of security with which the call data collected have to be transmitted as call records to the data postprocessing part of the system. 2 Definitions In the context of the technical requirements for metering and billing systems, as laid down in 5 of the Telecommunication Customer Protection Ordinance, the terms used have the meaning indicated below Customers Metering and billing system Users making use of call-dependent telecommunications. services for the public All technical facilities involved in the process of metering

- 2 - Data collection Data postprocessing Call data Master clock Official time standard Value of correction Calls of telecommunications services for the public Value-added service Call record Communication event Tariff distance Tariff time Per-second tariff Duration and billing, such as the facilities for generating, transmitting, collecting, storing and processing tariff and call data. Collection of call data in the node of a telecommunications network on a real-time basis and their storage as call records. All functions required for converting call data into communication events. The measurable data of a call, eg time at which the call started and ended and its duration, date, call number or code of the calling and of the called party. See also 5 of the Ordinance Regulating Data Protection for Telecommunications Carriers. Clock in the nodes of a telecommunications network, used for the purpose of establishing the time of data generation and collection. Reference system for the indication and distribution of the legal clock time by a time keeping institute. In Germany, it is customary to be connected to the official time standard of the Federal Institute of Physics and Metrology. Variance between the time indicated by the master clock and that of the official time standard. All telecommunications services used in connection with general network access to the public telecommunications network. These include 1. time- and distance-sensitive services (eg domestic or international long-distance calls). 2. time-sensitive and distance-insensitive services (eg local calls, value added calls, usage of supplementary services). 3. time-insensitive and distance-sensitive services. 4. time- and distance-insensitive services (eg calls to value-added services with fixed tariffs) 5. free-of-charge services (eg calls to emergency services, activation of supplementary services). Separate service offering characterised by special call processing, virtual access, separate tariffing or other optional features (eg Freephone, Shared Cost, Premium Rate, inquiry and absent subscriber services or conference calling). Unprocessed stored record of call data collected. There may be one or several call records per call. Call record for which a tariff has contractually been agreed. There is only one communication event per call, unless the duration of the call exceeds the accounting period. Aggregation of distances to different call destinations to which the same tariff applies, eg local tariff, long-distance tariff, international tariff. Comprises the period to which a tariff applies in dependence on the time - eg time of day or day of a week. Contractually agreed rate for the span of one second in the course of a call Length of a periodically recurring time span whose multiple is used to determine the duration of a call

- 3-3 Requirements concerning the accuracy of data collection Accuracy of metering means the degree of approximation between the call data stored in the call records and the actual call data. The actual beginning of a call is the time instant, determined on the basis of the time of the official time standard, at which the connection has been set up end to end. The actual end of a call is the time instant, determined on the basis of the time of the official time standard, at which the connection is released. The requirement of metering accuracy is met by compliance with the requirements set out below for call metering, for the master clock and for the recording of the distance: 3.1 Time metering The time instances used for determining the duration of a call, which can be derived from the time instances stored in the call records for the purpose of establishing the beginning and the end of a call as well as its duration - adjusted by values of correction, if need be - may not differ from the actual time instances of the calls by more than 500 milliseconds. This applies also if the time instances are measured by a facility that is operated at a location other than that of the through-switching equipment. As regards rate-relevant telecommunications services used additionally during a call, eg supplementary services, the services as well as the beginning and the end of their use and duration have to be stored. This is subject to the same requirements as apply to the recording of the time at which a call starts and ands. If the duration of the call and the use of the system respectively is determined by the number of clock pulses, the following requirements have to be met: Up to an interval length of 100 seconds, the clock pulse interval billed may deviate from the contractually agreed clock pulse interval by a maximum of 1%, if this value is exceeded the deviation may not be more than 1 second. The beginning of the interval may deviate from the actual beginning of the call by not more than 500 milliseconds. The fraction of a clock pulse interval at the end of a call may be counted as a full interval. 3.2 Master clock The accuracy, ie the deviation of the master clock in dependence on the time, may not exceed 10exp(-7) within every second. The time of the master clock may deviate from the time of the official time standard by up to 3 seconds. The time of the master clock has to be constantly compared with the time of the official time standard, if need be it has to be corrected and, if so, the value of correction has to be recorded. As the requirement of comparing the accuracy of the master clock on the one hand and the absolute deviation of the time of the master clock on the other depends on the time of the official time standard, the comparison has to be carried out time and again until the permissible metering deviation (500 milliseconds) and also the absolute deviation of the time

- 4 - of the master clock (up to 3 seconds) is not exceeded any more, and the value of correction has to be corrected accordingly. The time instances to be stored in the call record for the beginning and the end of the call or use of the system and the associate values of correction are dependent on the master clock: a) If the master clock meets all the requirements mentioned under 3.1, ie if the time registered deviates from the actual time related to the official time standard by a maximum of 500 milliseconds, the time instances measured by the master clock can be stored directly in the call record and can be used for computing the duration of the call within the framework of data postprocessing. b) If the master clock does not meet the requirements completely, ie if its deviation from the official time standard is up to 3 seconds, the time instances registered by the master clock for the beginning and the end of the call can be corrected by the value of correction even before they are stored in the call record. Otherwise the value of correction, together with the time instances registered by the master clock for the beginning and the end of the call have to be stored and transmitted to the data postprocessing part of the system in such a way that they can be allocated to the call records there and used for correcting the time instances registered. Appropriate security measures have to be applied in order to prevent the master clock from taking the wrong time. 3.3 Recording of the distance The distance between the subscriber lines involved in a call is determined by the call numbers registered for the calling and the called party. In the case of local calls, all digits of the subscriber call number of the calling party and a minimum of three highest-value digits of the subscriber call number of the called party have to be recorded. In the case of long-distance calls all digits of the nationally significant call number of the calling party and at least seven highest-value digits of the nationally significant call number of the called party have to be recorded. In the case of calls to value-added services all digits of the nationally significant call number of the calling party and of the called (virtual) party have to be recorded. 4 Requirements regarding data postprocessing accuracy To take into consideration the distance between the subscriber lines involved in a call the relevant rate for the respective distance is determined on the basis of the call numbers of the calling and called party recorded. The tariff to be charged for the respective call has to be determined on the basis of the rate applicable to the relevant distance and the tariff time. The requirements listed below for the computation of the charge apply both to the computation of call charges and the computation of usage charges for telecommunications services used additionally in connection with a call.

- 5-4.1 Accuracy of charging when time is recorded continuously 4.1.1 Computation of the duration of the call and usage respectively The computation of the call duration depends on the data recorded prior to the computation process: If, during data collection, the time instances of the beginning and the end of a call were stored in the call record with the accuracy that is required for the computation of the call duration, these time instances can be used directly for the computation of the call duration. Otherwise the time instances recorded have to be adjusted by the value of correction before they can be used for the computation of the call duration. The call duration has to be calculated on the basis of the difference between the beginning and the end of a call with an accuracy of 1 second. The time of usage of telecommunications services demanded additionally during a call, eg supplementary services, has to be computed on the basis of the difference between the beginning and the end of usage with an accuracy of 1 second. If the computed duration of the call or usage is broken down into contractually agreed intervals, the number of the intervals has to be computed by dividing the duration of the call or usage by the duration of the interval with an accuracy of at least two decimal places. Any further computation of the call charge is done in accordance with 4.2. 4.1.2 Tariff conversion Tariffs deviating from the per-second tariff, eg per-minute tariffs, have to be converted to per-second tariffs, unless otherwise provided for in a contract. The per-second tariff is computed as a fraction of the relevant tariff, eg 1/60 of the per-minute tariff, and is included in any further computations with an accuracy of four decimal places. 4.1.3 Computation of the duration of the call or usage If no other special contractual conditions have been agreed regarding the accounting arrangements, the call charge is computed by multiplying the call duration with the net persecond tariff. If special contractual conditions have been agreed regarding the accounting arrangements, the call charge is computed by multiplying the call duration with the agreed net tariff. If a tariff has to be taken into consideration that changes during a call, eg if there is a changeover to another tariff or a non-linear tariff model, the duration of the individual partial calls has to be determined first. The individual partial call charges are computed by multiplying the duration of the individual partial calls with the net tariff applicable to this partial call. The call charge is computed by adding up the individual partial call charges. 4.2 Accuracy of charging for the intervals recorded between time pulses 4.2.1 Tariff conversion Tariffs deviating from the tariff per interval between time pulses, eg per-minute tariffs, have to be converted to tariffs per interval between time pulses, unless otherwise provided for in a contract. The tariff per interval between time pulses is computed as a fraction of the relevant

- 6 - tariff, eg n/60 of the per-minute tariff whereby n = length of an interval expressed in seconds, and is included in any further computations with an accuracy of four decimal places. 4.2.2 Computation of the call or usage charge If no other special contractual conditions have been agreed regarding the accounting arrangements, the call charge is computed by multiplying the recorded or computed number of intervals with the agreed net tariff per interval. If special contractual conditions have been agreed regarding the accounting arrangements, eg discounts or mark-ups on individual calls, the call charge is computed by multiplying the recorded or computed number of intervals with the agreed net tariff per interval. If a tariff has to be taken into consideration that changes during a call, eg if there is a changeover to another tariff or a non-linear tariff model, the number of intervals of the individual partial calls has to be determined first. The individual partial call charges are computed by multiplying the number of intervals of the individual partial calls with the net tariff applicable to this partial call. The call charge is computed by adding up the individual partial call charges. 4.3 Discounts and mark-ups When the call or usage charge has been computed, any discounts or mark-ups on individual calls or usage have to be taken into consideration. In a communication event the computed call or usage charge has to be indicated with an accuracy of four decimal places of the amount expressed in DM or Euros; in addition, the fifth decimal place has to be rounded in line with good commercial practice. 4.4 Accounting of individual communication events on a credit basis The price for every communication event is determined on the basis of net tariffs. As far as technically possible and contractually agreed, discounts or mark-ups have to be taken into consideration. The statutory turnover tax is added to the call or usage charge. The resulting gross rate has to be computed with an accuracy of two decimal places of the amount expressed in DM or Euros. The contractually agreed granularity has to be deducted from the credit amount. 5 Requirements concerning data transmission When call records are transmitted from the data collection part of the system to the data postprocessing part of the system, losses, multiplications or modifications may occur with a frequency of not more than 10 exp(-10). 6 Recording of measures All measures taken in the process of metering and charging by which charges may be influenced, have to be recorded, preferably by the equipment that is affected by a particular

- 7 - measure. At the same time the system should be able, as far as possible, to allocate the time at which a particular measure was taken, to the respective calls. The data recorded have to be kept by the provider at least for the period of time laid down in 6(3) of the Telecommunications Carriers Data Protection Ordinance for the purposes of call data storage. It must be ensured that any outages of the metering and billing system do not lead to unjustified charges within the framework of call charge accounting. 7 Proof of compliance Under 5(3) of the Telecommunication Customer Protection Ordinance proof of compliance with these technical requirements has to be furnished. The procedure to be followed will be the subject matter of an administrative order to be published in the Official Gazette.