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<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Dear all,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I am a PhD student at EPFL, <st1:place w:st="on"><st1:country-region
w:st="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=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='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="on"><st1:City w:st="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=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><font
size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial'><span
style='mso-list:Ignore'>1)<font size=1 face="Times New Roman"><span
style='font:7.0pt "Times New Roman"'> </span></font></span></span></font><![endif]><font
size=2 face=Arial><span lang=EN-GB style='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=MsoNormal style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><font
size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial'><span
style='mso-list:Ignore'>2)<font size=1 face="Times New Roman"><span
style='font:7.0pt "Times New Roman"'> </span></font></span></span></font><![endif]><font
size=2 face=Arial><span lang=EN-GB style='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=MsoNormal style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><font
size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial'><span
style='mso-list:Ignore'>3)<font size=1 face="Times New Roman"><span
style='font:7.0pt "Times New Roman"'> </span></font></span></span></font><![endif]><font
size=2 face=Arial><span lang=EN-GB style='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="on"><st1:City w:st="on">Abilene</st1:City></st1:place>
only by traversing the commercial Internet?<o:p></o:p></span></font></p>
<p class=MsoNormal style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><font
size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial'><span
style='mso-list:Ignore'>4)<font size=1 face="Times New Roman"><span
style='font:7.0pt "Times New Roman"'> </span></font></span></span></font><![endif]><font
size=2 face=Arial><span lang=EN-GB style='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=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Thank you in advance for your comments.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Maciej Kurant<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=PL
style='font-size:10.0pt;font-family:"Courier New"'>=============================================<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=PL
style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=PL
style='font-size:10.0pt;font-family:"Courier New"'>EPFL IC ISC LCA3<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=PL
style='font-size:10.0pt;font-family:"Courier New"'>Maciej Kurant<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=DE-CH
style='font-size:10.0pt;font-family:"Courier New"'>PhD Student<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=DE-CH
style='font-size:10.0pt;font-family:"Courier New"'>CH-1015 Lausanne,
Switzerland<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=DE-CH
style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=DE-CH
style='font-size:10.0pt;font-family:"Courier New"'>web site: </span></font><font
size=2 face="Courier New"><span lang=FR-CH style='font-size:10.0pt;font-family:
"Courier New"'><a href="http://lcawww.epfl.ch/kurant"><span lang=DE-CH>http://lcawww.epfl.ch/kurant</span></a></span></font><span
lang=DE-CH><o:p></o:p></span></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=DE-CH
style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face="Courier New"><span lang=FR-CH
style='font-size:10.0pt;font-family:"Courier New"'>=============================================</span></font><span
lang=FR-CH><o:p></o:p></span></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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