The Unpredictable Certainty White Papers (1997) / Chapter Skim
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Post-NSFNET Statistics Collection
Post-NSFNET Statistics Collection
Pages 85-96
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From page 85... ...
The transition to the new NSFNET program, with commercially operated sentences providing both regional service as well as cross-service provider switching points, or network access points (NAPs) , will render statistics collection a much more difficult endeavor.
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From page 86... ...
As wad the NSFNET program, NSF was not in a position to specify in detail what statistics the network manager should collect since NSF did not know as much about the technology as the providers themselves did. The situation is similar with other emerging network service providers, whose understanding of the technology and what statistics collection is possible is likely to exceed that of NSF.
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From page 87... ...
A furler contributing factor to the lag of Internet traffic modeling behind that of telephony traffic is the early financial structure of the Internet.
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From page 88... ...
However, it is at just such a time, marked ironically with the cessation of the NSFNET statistics, that a baseline architectural mode} for statistics collection is most cntical, so Mat customers can trust the performance and integrity of the services they procure from their network service providers, and so Mat service providers do not tie their hands behind their backs in terms of being able to preserve robustness, or forfend demise, of their own clouds. Cost-benefit tradeoff: accurately characterize the workload on the network so that NAPs and NSPs can optimize (read, maintain)
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From page 89... ...
We must rely on WAN traffic characterization studies that focus on a single or a few attachment points to transit networks to investigate shorter-term aspects of certain kinds of Internet traffic, e.g., TCP [101, TCP and UDP [~ Id, and dins [121. The authors have devoted much attention In the last 2 years to investigating the usefi~Iness, relevance, and p~icality of a wide variety of operationally collected statistics for w~de-area backbone networks.
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From page 90... ...
In addition to our studies of operational statistics, we have also undertaken several studies that collect more comprehensive Internet traffic flow statistics, and we have developed a methodology for descnbing those flows in terms of their impact on an aggregate Internet workload. We have developed a methodology for profiling Internet traffic flows which draws on previous flow models [14]
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From page 91... ...
However, regulation may be necessary In order to foster a healthy competitive network environment where consumers can make educated decisions regarding which network service providers to patronize. A key requirement in analyzing the relative performance of and customer satisfaction with network service providers is public availability of statistics that measure their capacity, reliability, security, integrity, and performance.
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From page 92... ...
Technically difficult variables to collect, due to the high resolution polling required, include queue lengths and route changes. Although such vanables would be useful for many research topics in Internet traffic characterization, operationally collected statistics Dill likely not be able to support them.
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From page 93... ...
Because flow assessment requires comprehensive and detailed statistics collection, we recognize that the NAPs and other service providers may not be able to afford to continuously monitor flow characteristics on an Operational basis. Nonetheless we imagine that NAP operators wall find it useful to undertake traffic flow assessment at least penodically to obtain a more accurate picture of the workload their infrastructure must support.
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From page 94... ...
As a result, the gap has grown large between the unambiguous results of confined experiments that target isolated environments, and the largely unknown characteristics of the extensive Internet infrastructure that is heading toward global ubiquity Empirical investigation and improved methodology for doing so can improve current operational statistics collection architectures, allowing service providers to prepare for more demanding use of the infrastructure and allowing network analysts to develop more accurate Internet models. In short, we can contribute to a greater understanding of real computer networks of pervasive scale by reducing He gaps among (~)
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From page 95... ...
1994. "Web Traffic Characterization: An Assessment of the Impact of Caching Documents from NCSA's Web Server," Second International World Wide Web Conference, October.
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From page 96... ...
1995. "Internet Traffic Flow Profiling," IEEE Journal on Selected Areas in Communications, forthcoming.
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