[93462] in North American Network Operators' Group
RE: How to get a list of research and academic ISP ?
daemon@ATHENA.MIT.EDU (Maciej Kurant)
Mon Nov 20 15:14:31 2006
From: "Maciej Kurant" <maciej.kurant@epfl.ch>
To: <nanog@merit.edu>
Date: Mon, 20 Nov 2006 21:13:39 +0100
In-reply-to:
Errors-To: owner-nanog@merit.edu
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Dear All,
Thank you very much for numerous and quick replies for my email. I must say
that nanog list is really highly responsive.
I needed some time to digest your comments and try some new ideas. I share
the preliminary results with you now, begging for further comments.
The problem was (and still is) to find a good heuristic to distinguish
between commercial (COM) and educational/research/academic (EDU) ASes.
*EDU_Abilene*
My first approach (see my original email) was to extract a list of all
destinations announced by Abilene. (The assumption is that Abilene generally
does not announce commercial prefixes.) This results in a list, call it
"EDU_Abilene", of 1333 ASes.
*EDU_description*
Some of you suggested looking at the names and descriptions of ASes. I used
the AS list available at:
<http://www.multicasttech.com/status/asn_expand.txt>
http://www.multicasttech.com/status/asn_expand.txt
and searched the last column ("Organization") for the following strings:
"Universit|Univerz|Universida|research|education|science|scientif|academic|c
ollege|institut|laborator|school|ecole|
edu|R&D|library|academy|Etudes"
This approach finds 1796 "educational" ASes, call this set
"EDU_description".
Of course, these two lists overlap, but less than I expected. In particular:
len(EDU_Abilene)=1333
len(EDU_description)=1796
union(EDU_Abilene, EDU_description)=2269
intersection(EDU_Abilene, EDU_description)=860
For many reasons, these lists are far from being very precise. For instance
EDU_Abilene contains AS 7132 (AT&T) and AS 8075 (Microsoft). Therefore I
need further data sets or filtering methodology. This raises some questions:
1) What other EDU networks (preferably with BGP tables available in the web)
can I take as examples of ASes that (generally) do not announce commercial
prefixes? Based on them I could construct lists similar in spirit to
EDU_Abilene. I guess, the more the better.
2) Do you know of other lists, similar to
<http://www.multicasttech.com/status/asn_expand.txt>
http://www.multicasttech.com/status/asn_expand.txt ? Maybe a longer
description or a www related to an AS would help the method I use to create
EDU_description. Do you think the strings I use in my search are
appropriate?
*AS relationships*
Another approach is to exploit the AS relationships. Most of you agree that
usually EDU ASes are not providers for COM customers. This suggests a way to
detect false positives in EDU_Abilene and EDU_description (or in their
union). For every EDU node check how many COM customers it has, i.e., EDU
provider --- COM customer relationship. I used the AS graphs with inferred
relationships provided by CAIDA ( <http://as-rank.caida.org/data/2006/>
http://as-rank.caida.org/data/2006/). This method works well to find good
candidates for false positive, but they should not be blindly accepted. For
instance AS 7132 (AT&T) has the highest number of COM customers (615) and
should obviously belong to COM (it is a member of EDU_Abilene). In contrast,
a big component of the EDU backbone, AS 11537 (Abilene) has 66 COM
customers! In general there are about 50 EDU nodes with more than 10 COM
customers each.
3) What other "automatic" or "manual" approaches would you suggest? Or
improvements of the ones just described?
I will appreciate even the briefest comments and suggestions,
Maciej Kurant
_____
From: Maciej Kurant [mailto:maciej.kurant@epfl.ch]
Sent: mercredi, 15. novembre 2006 18:46
To: 'nanog@merit.edu'
Subject: How to get a list of research and academic ISP ?
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://abilene.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?
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?
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?
Thank you in advance for your comments.
Maciej Kurant
=============================================
EPFL IC ISC LCA3
Maciej Kurant
PhD Student
CH-1015 Lausanne, Switzerland
web site: <http://lcawww.epfl.ch/kurant> http://lcawww.epfl.ch/kurant
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<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Dear All,<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Thank you very much for numerous and quick =
replies
for my email. I must say that nanog list is really highly responsive. =
<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>I needed some time to digest your comments and =
try
some new ideas. I share the preliminary results with you now, begging =
for
further comments.<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>The problem was (and still is) to find a good
heuristic to distinguish between commercial (COM) and =
educational/research/academic
(EDU) ASes. <o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>*<b><span =
style=3D'font-weight:bold'>EDU_Abilene</span></b>*<o:p></o:p></span></fon=
t></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>My first approach (see my original email) was =
to
extract a list of all destinations announced by <st1:City =
w:st=3D"on"><st1:place
w:st=3D"on">Abilene</st1:place></st1:City>. (The assumption is that =
<st1:place
w:st=3D"on"><st1:City w:st=3D"on">Abilene</st1:City></st1:place> =
generally does not
announce commercial prefixes.) This results in a list, call it =
“EDU_Abilene”,
of 1333 ASes. <o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>*<b><span =
style=3D'font-weight:bold'>EDU_description</span></b>*<o:p></o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Some of you suggested looking at the names and
descriptions of ASes. I used the AS list available at: =
<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><a
href=3D"http://www.multicasttech.com/status/asn_expand.txt"><font =
color=3Dblack><span
style=3D'color:windowtext'>http://www.multicasttech.com/status/asn_expand=
.txt</span></font></a>
<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>and searched the last column
("Organization") for the following =
strings:<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>"Universit|Univerz|Universida|research|edu=
cation|science|scientif|academic|college|institut|laborator|school|ecole|=
<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>edu|R&D|library|academy|Etudes"<o:p></=
o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>This approach finds 1796 =
"educational"
ASes, call this set =
“EDU_description”.<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Of course, these two lists overlap, but less =
than I
expected. In particular:<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>len(EDU_Abilene)=3D1333<o:p></o:p></span></font=
></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>len(EDU_description)=3D1796<o:p></o:p></span></=
font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>union(EDU_Abilene, =
EDU_description)=3D2269<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>intersection(EDU_Abilene, =
EDU_description)=3D860<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>For many reasons, these lists are far from =
being very
precise. For instance EDU_Abilene contains AS 7132 (AT&T) and AS =
8075 (Microsoft).
Therefore I need further data sets or filtering methodology. This raises =
some
questions:<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>1) What other EDU networks (preferably with =
BGP
tables available in the web) can I take as examples of ASes that =
(generally) do
not announce commercial prefixes? Based on them I could construct lists =
similar
in spirit to EDU_Abilene. I guess, the more the better. =
<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>2) Do you know of other lists, similar to <a
href=3D"http://www.multicasttech.com/status/asn_expand.txt"><font =
color=3Dblack><span
style=3D'color:windowtext'>http://www.multicasttech.com/status/asn_expand=
.txt</span></font></a>
? Maybe a longer description or a www related to an AS would help =
the
method I use to create EDU_description. Do you think the strings I use =
in my
search are appropriate?<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>*AS =
relationships*<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Another approach is to exploit the AS =
relationships. Most
of you agree that usually EDU ASes are not providers for COM customers. =
This
suggests a way to detect false positives in EDU_Abilene and =
EDU_description (or
in their union). For every EDU node check how many COM customers it has, =
i.e., EDU
provider --- COM customer relationship. I used the AS graphs with =
inferred relationships
provided by CAIDA (<a href=3D"http://as-rank.caida.org/data/2006/"><font
color=3Dblack><span =
style=3D'color:windowtext'>http://as-rank.caida.org/data/2006/</span></fo=
nt></a>).
This method works well to find good candidates for false positive, but =
they
should not be blindly accepted. For instance AS 7132 (AT&T) has the =
highest
number of COM customers (615) and should obviously belong to COM (it is =
a
member of EDU_Abilene). In contrast, a big component of the EDU =
backbone, AS
11537 (<st1:City w:st=3D"on"><st1:place =
w:st=3D"on">Abilene</st1:place></st1:City>)
has 66 COM customers! In general there are about 50 EDU nodes with more =
than 10
COM customers each. <o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>3) What other “automatic” or =
“manual”
approaches would you suggest? Or improvements of the ones just =
described? <o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>I will appreciate even the briefest comments =
and
suggestions,<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Maciej Kurant<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
lang=3DEN-GB
style=3D'font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p>=
</span></font></p>
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<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span lang=3DEN-US style=3D'font-size:12.0pt'>
<hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1>
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<p class=3DMsoNormal><b><font size=3D2 face=3DTahoma><span lang=3DEN-US
style=3D'font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</spa=
n></font></b><font
size=3D2 face=3DTahoma><span lang=3DEN-US =
style=3D'font-size:10.0pt;font-family:Tahoma'>
Maciej Kurant [mailto:maciej.kurant@epfl.ch] <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> mercredi, 15. =
novembre 2006
18:46<br>
<b><span style=3D'font-weight:bold'>To:</span></b> '<st1:PersonName =
w:st=3D"on">nanog@merit.edu</st1:PersonName>'<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> How to get a =
list of
research and academic ISP ?</span></font><span =
lang=3DEN-US><o:p></o:p></span></p>
</div>
<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Dear all,<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>I am a PhD student at EPFL, <st1:place =
w:st=3D"on"><st1:country-region
w:st=3D"on">Switzerland</st1:country-region></st1:place>. My recent =
research
interest is in large scale differences between the commercial and =
academic parts
of the Internet. <o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Of course, in order to perform this kind of =
studies I
need a way to distinguish between these two worlds. I’ve learnt =
that <st1:place
w:st=3D"on"><st1:City w:st=3D"on">Abilene</st1:City></st1:place> 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://abilene.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: =
<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal =
style=3D'margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 =
lfo2'><![if !supportLists]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'><span
style=3D'mso-list:Ignore'>1)<font size=3D1 face=3D"Times New =
Roman"><span
style=3D'font:7.0pt "Times New =
Roman"'> =
</span></font></span></span></font><![endif]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'>Is
this approach to obtain a list of research and academic ISPs =
correct?<o:p></o:p></span></font></p>
<p class=3DMsoNormal =
style=3D'margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 =
lfo2'><![if !supportLists]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'><span
style=3D'mso-list:Ignore'>2)<font size=3D1 face=3D"Times New =
Roman"><span
style=3D'font:7.0pt "Times New =
Roman"'> =
</span></font></span></span></font><![endif]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'>Do
you maybe know of such lists compiled before? =
<o:p></o:p></span></font></p>
<p class=3DMsoNormal =
style=3D'margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 =
lfo2'><![if !supportLists]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'><span
style=3D'mso-list:Ignore'>3)<font size=3D1 face=3D"Times New =
Roman"><span
style=3D'font:7.0pt "Times New =
Roman"'> =
</span></font></span></span></font><![endif]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'>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 <st1:place w:st=3D"on"><st1:City =
w:st=3D"on">Abilene</st1:City></st1:place>
only by traversing the commercial Internet?<o:p></o:p></span></font></p>
<p class=3DMsoNormal =
style=3D'margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 =
lfo2'><![if !supportLists]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'><span
style=3D'mso-list:Ignore'>4)<font size=3D1 face=3D"Times New =
Roman"><span
style=3D'font:7.0pt "Times New =
Roman"'> =
</span></font></span></span></font><![endif]><font
size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:10.0pt;font-family:Arial'>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?<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Thank you in advance for your =
comments.<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Maciej Kurant<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span lang=3DPL
style=3D'font-size:10.0pt;font-family:"Courier =
New"'>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<o:p></=
o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span lang=3DPL
style=3D'font-size:10.0pt;font-family:"Courier =
New"'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span lang=3DPL
style=3D'font-size:10.0pt;font-family:"Courier New"'>EPFL IC ISC =
<st1:PersonName
w:st=3D"on">LCA3</st1:PersonName><o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span lang=3DPL
style=3D'font-size:10.0pt;font-family:"Courier New"'>Maciej =
Kurant<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span =
lang=3DDE-CH
style=3D'font-size:10.0pt;font-family:"Courier New"'>PhD =
Student<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span =
lang=3DDE-CH
style=3D'font-size:10.0pt;font-family:"Courier New"'>CH-1015 Lausanne,
Switzerland<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span =
lang=3DDE-CH
style=3D'font-size:10.0pt;font-family:"Courier =
New"'><o:p> </o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span =
lang=3DDE-CH
style=3D'font-size:10.0pt;font-family:"Courier New"'>web site: =
</span></font><font
size=3D2 face=3D"Courier New"><span lang=3DFR-CH =
style=3D'font-size:10.0pt;font-family:
"Courier New"'><a href=3D"http://lcawww.epfl.ch/kurant"><span =
lang=3DDE-CH>http://lcawww.epfl.ch/kurant</span></a></span></font><span
lang=3DDE-CH><o:p></o:p></span></p>
<p class=3DMsoNormal><font size=3D2 face=3D"Courier New"><span =
lang=3DDE-CH
style=3D'font-size:10.0pt;font-family:"Courier =
New"'><o:p> </o:p></span></font></p>
<p class=3DMsoAutoSig><font size=3D2 face=3D"Courier New"><span =
lang=3DFR-CH
style=3D'font-size:10.0pt;font-family:"Courier =
New"'>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D</span>=
</font><span
lang=3DFR-CH><o:p></o:p></span></p>
<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p> </o:p></span></font></p>
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