Practical VoIP Using VOCAL

Chapter 18. Quality of Service and Billing

This chapter is a combined view of billing and Quality of Service issues. VOCAL does not include a billing server, but has a Call Detail Record (CDR) server that can either cache billing information or send it via the Remote Authentication Dial In User Service (RADIUS, RFCs 2138 and 2139) protocol to a third-party billing server. VOCAL also comes with an Open Settlement Protocol (OSP) stack that permits different VoIP systems to share billing information for cross-network calling through the use of a common clearing house. OSP is a product of the Telecommunication And Internet Protocol Harmonization Over Networks (TIPHON) project at the European Telecommunications Standards Institute (ETSI),http://http://www.etsi.org.

QoS is an advanced topic: while the protocols and technology exist to ensure some sort of QoS between IP networks, the practice has not caught up to the theory. Some organizations offer point-to-point IP backbones that are useful for VoIP traffic; however, the adoption of packet telephony will have to expand by several orders of magnitude before the business incentives to improve QoS push a truly ubiquitous, reliable service into the realm of practical and affordable reality. In many cases, service providers simply engineer a network to have plenty of bandwidth and ignore per-call QoS.

Although these topics are normally diverse and would normally deserve separate treatment there is, in VOCAL, a commonality that brings these ...