To: Frank A. Coluccio who wrote (769 ) 12/19/1999 4:38:00 AM From: Frank A. Coluccio Respond to of 1782
re: Internet bandwidth pricing, ex-post Question: Should an ISP pay another ISP or backbone provider for bandwidth if the message never gets to or retrieved from the other end of the pipe? Here's an interesting paper I picked up at the M.I.T. Itel Site:itel.mit.edu The paper is titled: "Ex-Post Internet Pricing" Joseph Bailey, Jose Nagel, S. Raghavan From: marengoresearch.com Abstract "Pricing Internet bandwidth is of growing importance as the Internet grows and matures. While many residential consumers have "flat rate" Internet pricing, the pricing policies facing campus, regional, and metropolitan-area networks are becoming more complex. While it may be possible to price every bit or packet of data, this pricing policy requires significantly additional accounting and billing overhead to make it practical. Instead, many Internet Service Providers (ISPs) are using a form of aggregate statistics to determine prices. This class of pricing policies---wherein the pricing algorithm is determined ex-ante but the price is calculated after the fact---we call "ex-post" because the prices are determined after the traffic has been sent. "In this paper, we construct a framework for classifying pricing and allocation policies. We use this framework to simultaneously examine economic and technology approaches to providing differentiated services on the Internet. The paper discusses the different combinations of pricing and allocation policies pointing out existing and proposed pricing/allocation policy combinations. We point out the advantages of an ex-post pricing model for all allocation policies, including reduced overhead while more accurately setting prices based on effective network usage. "Expanding on the potential for ex-post pricing, we construct a general form of an ex-post pricing model. This model determines prices using metrics describing both the utilization and burstiness of network traffic. We then apply the general form of the ex-post pricing model using two different ways of characterizing utilization and burstiness: 1) mean rate and the Hurst parameter for self-similar traffic, and 2) fitting leaky token buckets (LTBs) to traffic traces to determine the rate (utilization) and depth (burstiness) of the LTB. "Further, we show how the model can be applied to different allocation policies. "Finally, we discuss the implications of ex-post Internet pricing. We discuss the granularity or sampling rate that is reasonable given the cost of collecting traffic data and the need for accurate representation of the traffic using aggregate statistics. We also explore the possibility of new business opportunities for ISPs to use ex-post Internet pricing to better manage their Internet Protocol (IP) networks." Continued at:marengoresearch.com