PhDNew services are emerging rapidly within the world of telecommunications. Charging
strategies that were appropriate for individual transfer capabilities are no longer appropriate
for an integrated broadband communications network. There is currently a range of
technologies (such as cable television, telephony and narrow band ISDN) for the different
services in use and a limited number of charging schemes are applicable for each of the
underlying technologies irrespective of the services used over it. Difficulties arise when a
wide range of services has to be supported on the same integrated technology such as
asynchronous transfer mode (ATM); in such cases the type of service in use and the impact
it has on the network becomes much more important. The subject of this thesis, therefore,
is the charging strategies for integrated broadband communications networks. That is, the
identification of the requirements associated with ATM charging schemes and the proposal
of a new approach to charging for ATM called the “quality of service based charging
scheme”.
Charging for ATM is influenced by three important components: the type and content of a
service being offered; the type of customer using the services; and the traffic characteristics
belonging to the application supporting the services. The first two issues will largely be
dependent on the business and regulatory requirements of the operators. The last item, and
an essential one for ATM, is the bridge between technology and business; how are the
resources used by a service quantified? Charging that is based on resource usage at the
network level was the prime focus of the research reported here.
With the proposed charging scheme, a distinction is first made between the four different
ATM transfer capabilities that will support various services and the different quality of
service requirements that may be applicable to each of them. Then, resources are
distributed among buffers set-up to support the combination of these transfer capabilities
and quality of services. The buffers are dimensioned according to the M/D/1/K and the
ND/D/1 queuing analysis to determine the buffer efficiency and quality of service
requirements. This dimensioning provides the basis for fixing the price per unit of resource
and time. The actual resource used by a connection is based on the volume of cells
transmitted or peak cell rate allocation in combination with traffic shapers if appropriate.
Shapers are also dimensioned using the quality of service parameters. Since the buffer
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efficiency is dependent on the quality of service requirements, users (customers) of ATM
networks buy quality of service. The actual price of a connection is further subjected to a
number of transformations based on the size of the resource purchased, the time of the day
at which a connection is made, and the geographical locality of the destination switch.
It is demonstrated that the proposed charging scheme meets all the requirements of
customers and of network operators. In addition the result of the comparison of the new
scheme with a number of existing, prominent, ATM charging schemes is presented,
showing that the performance of the proposed scheme is better in terms of meeting the
expectations of both the customers and the network operators
