-----Original Message----- From: Francois Menard [mailto:francois@menards.ca] Sent: Sunday, March 01, 2009 11:49 AM To: Lorell Hathcock Cc: 'nanog list' Subject: Re: DPI or Flow Management
Its like the post office getting envolopes by the truckload, then opening each envelope, read the content, to decide when to send the opened letter for delivery, either by foot or car, claiming that such a decision process will prevent envelopes from flooding the post office, coming into the post office for delivery in the last mile.
On the other hand, traffic management such as flow management, deal with stuff differently by ensuring that the envelopes do not get to the post office too fast, thus permitting the letters be dispatched always by car, except those envelopes which are arriving to the post office, exhibiting behaviour of P2P, which are then sent for delivery by foot. In this latter case, the envelopes are never opened.
There is, however, at least one more dimension with postal or package delivery services. They offer different delivery priorities with different pricing, may have surcharges or refuse large content that the physical transport technically could carry, and offer sender-pays and receiver-pays options. A few specialized cases do apply as well, such as some package delivery services accepting and handling hazardous materials only with declaration and surcharges. It seems that this discussion emphasizes technical capabilities, which certainly are relevant, but does not necessarily consider economic incentives or disincentives. We are probably in agreement that either DPI or traffic analysis could identify high-volume P2P; how does one deal with the customer assumption that they "should" be able to do whatever they like? Content distribution networks and caches do allow a much cleaner economic model, if not as convenient.