Kent W. England writes:
Here are some examples:
2. Identify which % of traffic, if any, has regional locality. For pure Internet traffic, the probability that the source and destinatino of traffic are within the same metropolitan area tends to be low (10% or lower for metros within the US).
This is true only so long as the density of the Internet is low. This is so because so long as the density is low, few of your neighbors will be on the Internet and therefore local issues are irrelevant. However, at some point, the density of the Internet gets to a critical point, say 30% to 40%. At that point a pizza parlor owner says to himself "two out of every five of my customers are on the Internet. Perhaps I need a web page." And, suddenly, pizza on the Net makes a lot of sense and the traffic patterns shift. As the density grows to 90%, local traffic becomes dominant over distant traffic.
Even in the scenario where physical proximity automatically implied network proximity, I think the assumption that local traffic will dominate communications needs to be revisited. It is true today, only because that is how people live lives and conduct business _today_. The concept of "community" today is geographical.. the communities of tommorrow may not be so restricted.
Another example is distributed web hosting. When distributed web hosting takes off, your backbone will be heavily discounted and your peripheral interconnect bandwidth will be woefully short. Web traffic will zoom as performance dramatically improves, but your backbone bandwidth will drop. That breaks your traffic model.
This is true of a business model based around content distrubution only. Most ISPs of size will have both publishers and consumers of information so the backbones utilization should be balanced.
So, by all means, do your traffic studies, but be prepared to throw them out or re-write them when the environment changes. Then throw bandwidth where it will do the most good. :-)
No debate here.
--Kent
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