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<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=640224523-30112004>David,</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=640224523-30112004></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=640224523-30112004>Yeah,
the code has been in beta for a while. </SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=640224523-30112004></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=640224523-30112004>It is
UDP based. If all UDP is blocked then it won't work and wont be
attempted. We do a lot to first ensure that you can receive solicited UDP
which is what this feature relies on. i.e. If you send a packet to X via
UDP and you are behind a NAT/Firewall, you can receive a response back. In
LimeWire terms, you are then said to be firewall capable and your searches and
responses indicate this. </SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=640224523-30112004> </SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=640224523-30112004>There
are many ways to negotiate the initiation of the connection on both sides.
LimeWire has a concept of a push proxy for firewalled hosts so we actually use
that to deliver a special PUSH message that tells the host to initiate a UDP
connection to ip:port. Both ends then start sending UDP messages at each
other and shortly thereafter, they should both be able to receive those
messages. A type of TCP style connection negotiation begins from
there. Just to be clear, this is not proxying. The only thing that
is proxied, is the PUSH message to trigger the actions of the
uploader.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=640224523-30112004></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=640224523-30112004>The
FAQ is out of date.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=640224523-30112004>Thanks</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=640224523-30112004>-greg</SPAN></FONT></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> p2p-hackers-bounces@zgp.org
[mailto:p2p-hackers-bounces@zgp.org]<B>On Behalf Of </B>David
Barrett<BR><B>Sent:</B> Tuesday, November 30, 2004 6:28 PM<BR><B>To:</B>
'Peer-to-peer development.'<BR><B>Subject:</B> RE: [p2p-hackers] Why UDP and
not TCP?<BR><BR></FONT></DIV>
<DIV class=Section1>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">How does the
Firewall-to-Firewall portion of Limewire work? Does it use un-firewalled
clients as relay servers? It doesn’t sound like it, but I thought that’s
the only solution that truly works in all
situations.<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">The “features
history” page mentions this on the entry for
8.12.2004:<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">“Firewall to Firewall
transfers allows two people behind firewalls to connect directly to each other
and transfer data. <B><SPAN style="FONT-WEIGHT: bold">This makes use of UDP,
and a third party to coordinate the initial messaging.</SPAN></B> … Normally,
firewalled users would only be able to download from other hosts who are not
firewalled, which is of course severely limited. With firewall to firewall
transfers, firewalled users can now access the full 100% of
hosts.”<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">This implies
something like the NAT-to-NAT trick works with firewalls also. I’m a
little shaky on how UDP works with firewalls, do both clients initiate a
conversation with a third party, and then the third party hands back
information IP/port information of the pre-established out-bound
connection? How does this work if the firewall simply blocks all UDP
traffic?<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">However, the website
is either out of date or there’s more to the story because the FAQ
says:<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><A
href="http://www.limewire.com/english/content/faq.shtml#fir1">http://www.limewire.com/english/content/faq.shtml#fir1</A>
<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">“Q: What
if I’m behind a firewall?<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">A:
LimeWire will work when a user is behind certain types of firewalls, but will
not work behind certain other types. <B><SPAN style="FONT-WEIGHT: bold">If you
are behind a firewall, you will not be able to download anything from a user
that’s also behind a firewall.</SPAN></B> In general, if you can connect (you
will see your “connection status” in the lower left hand corner of the
application) using LimeWire, you should be able to download and upload files,
but LimeWire will not work if you have either a web-only proxy or a SOCKS
proxy.”<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial color=navy
size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">What’s the full
story?<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">-david<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<DIV
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: blue 1.5pt solid; PADDING-TOP: 0in; BORDER-BOTTOM: medium none">
<DIV>
<DIV class=MsoNormal style="TEXT-ALIGN: center" align=center><FONT
face="Times New Roman" size=3><SPAN style="FONT-SIZE: 12pt">
<HR tabIndex=-1 align=center width="100%" SIZE=2>
</SPAN></FONT></DIV>
<P class=MsoNormal><B><FONT face=Tahoma size=2><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT
face=Tahoma size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">
p2p-hackers-bounces@zgp.org [mailto:p2p-hackers-bounces@zgp.org] <B><SPAN
style="FONT-WEIGHT: bold">On Behalf Of </SPAN></B>Greg Bildson<BR><B><SPAN
style="FONT-WEIGHT: bold">Sent:</SPAN></B> Tuesday, November 30, 2004 2:12
PM<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> Peer-to-peer
development.<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> RE:
[p2p-hackers] Why UDP and not TCP?</SPAN></FONT><o:p></o:p></P></DIV>
<P class=MsoNormal><FONT face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"><o:p> </o:p></SPAN></FONT></P>
<DIV>
<P class=MsoNormal><FONT face=Arial color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial">If you believe that
there are problems with LimeWire, you should submit them to <A
href="mailto:bugs@limewire">bugs@limewire</A> and they will be looked
into promptly. If you have not already, you should also upgrade to
version 4.2.3 to get rid of some potential startup issues with old
GWebcaches.<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial">LimeWire is a "good
new" p2p application - check out that firewall-to-firewall transfer in the new
version. ;)<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial">Thanks<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial">-greg<o:p></o:p></SPAN></FONT></P></DIV>
<BLOCKQUOTE
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0in; MARGIN: 5pt 0in 5pt 3.75pt; BORDER-LEFT: black 1.5pt solid; PADDING-TOP: 0in; BORDER-BOTTOM: medium none">
<P class=MsoNormal style="MARGIN-BOTTOM: 12pt"><FONT face=Tahoma color=black
size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Tahoma">-----Original
Message-----<BR><B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B>
p2p-hackers-bounces@zgp.org [mailto:p2p-hackers-bounces@zgp.org]<B><SPAN
style="FONT-WEIGHT: bold">On Behalf Of
</SPAN></B>Digitalgruvmoves@aol.com<BR><B><SPAN
style="FONT-WEIGHT: bold">Sent:</SPAN></B> Monday, November 29, 2004 9:10
PM<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B>
p2p-hackers@zgp.org<BR><B><SPAN
style="FONT-WEIGHT: bold">Subject:</SPAN></B> Re: [p2p-hackers] Why UDP and
not TCP?</SPAN></FONT><FONT face=Arial color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial"><o:p></o:p></SPAN></FONT></P>
<DIV>
<P class=MsoNormal><FONT id=role_document face=Arial color=black
size=2><SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial">Whats
a good new p2p filesharing download to use? Limeware just started acting
nuts.<o:p></o:p></SPAN></FONT></P></DIV></BLOCKQUOTE></DIV></DIV></BLOCKQUOTE></BODY></HTML>