Your statement makes something of a presumption as to the architecture of a network. In many networks, edge aggregation devices do not participate in backbone routing, but simply pass the traffic they are aggregating into the core.

My first reaction, as well. However, I was reminded by Andrew Odlyzko that the cable tv industry's (MSOs') peering universe constitute a form of flattened 'edge', if one were to consider the larger Internet's core against the MSO community, which makes for another form of interesting analysis, since much of today's (especially more capacious) residential "broadband" flows begin and end on MSOs' networks, and sometimes never touch the larger core, fwiw. And this opens the door to other forms of "walled garden" environments, including intranets, some providers' CDNs, extranets, and so on. Frank A. Coluccio DTI Consulting Inc. 212-587-8150 Office 347-526-6788 Mobile On Sun Feb 18 10:54 , Andrew Lee sent:

Hi Chris

Your statement makes something of a presumption as to the architecture of a network. In many networks, edge aggregation devices do not participate in backbone routing, but simply pass the traffic they are aggregating into the core.

One fairly well instrumented network that does have this edge/core collapsed model is the Internet2 network. You can find a lot of traffic and other data for the network at: http://noc.net.internet2.edu/i2network/live-network-status.html You should be able to extract all the info you need from there.

/Andrew

Chris Develder wrote, On 2/18/07 5:46 AM:

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Hi All,

In preparation of a course, I'm looking for reference material (paper, report, talk...) giving real world data on the amount of transit traffic (ie. not locally dropped or added, but passing through to other (backbone) routers) in a "typical" edge router of a core network, esp. ratio of local vs passthrough traffic (is it 30%, 40%...?) -- I don't need absolute figures, just realistic estimates of that ratio.

Any help in locating such references would be highly appreciated.

Kind regards, Chris