Summary

Table 17-1 summarizes the use cases covered in this chapter. For each scenario, the technical requirements are listed (for example, if a time stamp is necessary), followed by the proposed accounting technique.

Table 17-1. Comparison of Accounting Scenarios

Use Case	Applicability	Requirements and Prerequisites	Technique
Time-Based Billing	Dial-in Legacy voice pWLAN	Clock synchronization between the servers and an external NTP source	AAA infrastructure Voice switch Billing server SS7 infrastructure
pWLAN	Broadband for roaming users	Subscriber registration or credit card payment, etc.	AAA infrastructureBilling server
Dial-in	Low-speed modem access	Subscriber registration or pay-per-call services	AAABilling server
Volume-Based Billing	Broadband accessTransit and peering agreements	Metering of all conversations	Interface MIBs NetFlow IP Accounting IPDR
Residential broadband access (DSL or cable)	Broadband for residential users	Metering at access point	DOCSIS MIB SAMIS IPDR
Transit and peering agreements	Service provider interconnect	Identify traffic source and destination (on-net/off-net traffic)	Interface MIBs NetFlow IP Accounting MAC address
Destination-Sensitive Billing	Destination-Sensitive billing	Identify path and providers between source and destination; traffic correlation between user request and server response	BGP Policy Accounting NetFlow Mediation server Billing server
Time- and Distance-Based Billing	Legacy voice	Voice infrastructure	SS7 infrastructure
Service-Based Billing	Content provider, service selection, VoD	Application-based accounting and billing	Service application SSG SAMIS Billing server
VoD	Broadband for residential users	Subscriber registration or credit card payment	AAA infrastructure Content server Billing server
Enterprise Departmental Charge Back	Sharing Internet access	Aggregate users to departments	Interface MIBsNetFlow
Flat Rate	"All you can eat"	Sufficient bandwidth	Nothing