An embedded charging approach for RSVP

Charging mechanisms are needed to protect an integrated services network from arbitrary resource reservations and to create a funding mechanism to extend network capacity at the most desired locations at the expense of those users that actually use these resources. In this paper, we describe a charging model that can be embedded in the RSVP (Resource ReSerVation Protocol) architecture. Our model is open and flexible in that it imposes little or no restrictions to the pricing policy of network providers or the usage behaviour of end-users. At the same time, it provides mechanisms to enable fine-grained charging of network communication. After a user-centric identification of requirements for charging mechanisms, a formal framework is presented to model the prices and payments. We present protocol elements and an implementation rationale to realize our charging model. Furthermore, we identify potential problems that are inherent to RSVP with regard to precise charging and we point out future research issues towards a realistic charging architecture.