On Nov 15, 2006, at 12:46 PM, Maciej Kurant wrote:
> Dear all,
>
>
>
> I am a PhD student at EPFL, Switzerland. My recent
research
> interest is in large scale differences between the
commercial and
> academic parts of the Internet.
>
>
>
> Of course, in order to perform this kind of studies I
need a way to
> distinguish between these two worlds. I’ve learnt that
Abilene does
> not provide commercial connectivity. This means that
BGP prefixes
> and AS paths announced by Abilene BGP routers should
lead only to
> research and academic destinations. I have extracted
(from the BGP
> tables at http://abile
ne.internet2.edu/observatory) a list of all
> such destinations and obtained 1333 ASes (for data form
July 2006).
> The number looks reasonable, but I would like to be
sure that I am
> not making a mistake. Therefore I would be grateful if
you could
> answer the following questions:
>
>
>
> 1) Is this approach to obtain a list of research
and academic
> ISPs correct?
It's a way. The trouble is that
- most I2 As's also have "I1" connections and run
BGP on that as well.
- Any corporate member of I2 has the right to announce their
routes
into I2
What I would do is to take the list and look at the names
(on a list
such as
ht
tp://www.multicasttech.com/status/asn_expand.txt
From the name of the institution, you should be able to
tell in most
cases.
> 2) Do you maybe know of such lists compiled
before?
>
> 3) If I keep not only the destination ASes, but
also all ASes
> on the AS paths towards these destination I obtain a
list of about
> 1400 ASes. How should I understand this? Does it mean
that some
> research and academic destinations are reachable from
Abilene only
> by traversing the commercial Internet?
There are certainly some academic aggregation SP's -
NYSERNET and
CANARIE and RENATER (google on those) come to mind.
> 4) Of course, research and academic ASes are
often well
> connected to the commercial Internet. My guess is that
in most
> cases their peering relationship is
“customer-provider”, where
> commercial ASes are providers. Is it possible that an
academic AS
> is a provider for some commercial ASes? If so, does it
happen often?
It may happen, but probably not often.
>
>
> Thank you in advance for your comments.
>
> Maciej Kurant
>
>
Hope this helps.
Regards
Marshall Eubanks
>
>
>
>
> =============================================
>
>
>
> EPFL IC ISC LCA3
>
> Maciej Kurant
>
> PhD Student
>
> CH-1015 Lausanne, Switzerland
>
>
>
> web site: http://lcawww.epfl.ch/ku
rant
>
>
>
> =============================================
>
>
>
>
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