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<DIV><SPAN class=003535512-05032002><FONT face=Arial color=#0000ff size=2>Hi
Vasilis,</FONT></SPAN></DIV>
<DIV><SPAN class=003535512-05032002><FONT face=Arial color=#0000ff size=2>I dont
know if these would be interesting to you (I dont remember a whole lotta "pdf"
but some of the other stuff is there):</FONT></SPAN></DIV>
<DIV><SPAN class=003535512-05032002></SPAN><SPAN class=003535512-05032002><FONT
face=Arial color=#0000ff size=2>"End-to-end Reliability in UMTS: TCP over ARQ,
A-F.Canton and T.Chahed, Institute National des
Telecomminications"</FONT></SPAN></DIV>
<DIV><SPAN class=003535512-05032002><FONT face=Arial color=#0000ff size=2>and
Gorry&Mahesh's </FONT></SPAN><SPAN class=003535512-05032002><FONT face=Arial
color=#0000ff size=2>"Implications of Broadband Satellite BOD Algorithms on TCP
Performance" (sat stuff, what do you expect - sorry:)</FONT></SPAN></DIV>
<DIV><SPAN class=003535512-05032002><FONT face=Arial color=#0000ff size=2><A
href="mailto:tom_mchugh@inmarsat.com">tom_mchugh@inmarsat.com</A></FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
end2end-interest-admin@postel.org
[mailto:end2end-interest-admin@postel.org]<B>On Behalf Of </B>Vasilis
Friderikos<BR><B>Sent:</B> Tuesday, March 05, 2002 12:26<BR><B>To:</B>
end2end-interest@postel.org<BR><B>Subject:</B> [e2e] Outliers of delays on the
last (wireless) hop and the Internet<BR><B>Importance:</B>
High<BR><BR></FONT></DIV>
<DIV><FONT face=Arial size=2>
<DIV><FONT face=Arial size=2>I know that the topic that I will touch in the
next few lines is more close related to the PILC list, but the end2end list
(traditionally) has a more wider scope. There is a lot of research effort to
characterize the TCP performance in the last wireless hop ( a lot of
solutions[which some of them break the end-to-end principle]) but it seems
that there is a lack of more realistic performance evaluation where both the
Internet and wireless dynamics are taken into account. Mobile hosts which are
connected to a Web server which is let's say 20-25 hops away will
experience both kind of dynamics. So, it seems to me that we can characterize
the profile of this delay by a convolution of the delays in the Internet and
those due to the fluctuations on the wireless link (even though there is no
such global pdf that express the delays on the Internet,[i.e NLANR active
measurements].But, I'm not aware of pdf's of the delays on the last hop
for different access schemes( pdf that take into account the specific MAC
used,ARQ, transmission,coding-decoding).Also,concerning TCP issues, a
knowledge of possible outliers, the frequency of these outliers together
with the dynamics of the delays on the Internet would give a better (I think)
understanding of TCP{flavours} performance. If there is a work that
combines these two "worlds" I would like to be aware of. Thanks in
advance.</FONT></DIV>
<DIV> </DIV>
<DIV>Vasilis</DIV>
<DIV> </DIV></FONT></DIV>
<DIV> </DIV></BLOCKQUOTE><CODE><FONT SIZE=3><BR>
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