Re: Semi-Reliable UDP Layer

[email protected] Mon, 24 Sep 2012 18:11:35 +0000 (UTC)
Newsgroups	gmane.network.gnutella.devel
Organization	Home, Grenoble, France
Message-ID	<[email protected]>
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Quoting Michael Green <[email protected]> from ml.gnutella.dev-forum:
:With today's overall reliability of Internet connections, that seems
:unnecessary.

Beware of the word "reliability" :-)

IP packets do get dropped in case of traffic congestion.  And this is likely
to happen on the way out, from busy ADSL connections, or at the ISP level
in case there are exceptional traffic peaks.  The less IP has to fragment,
the less chances the whole message will be lost.

Therefore UDP/IP is "unreliable", which does not prevent most of the UDP
traffic to come through, of course!

Now everyone is taking care of not dropping packets unless it's absolutely
necessary, due to the avalanche effect that occurs when every protocol on
top of IP has to retransmit!

That's probably what you meant by "reliability".

Raphael

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      <p>Quoting Michael Green &lt;<a href="mailto:myatus%40gmail.com">[email protected]</a>&gt; from ml.gnutella.dev-forum:<br>
:With today's overall reliability of Internet connections, that seems<br>
:unnecessary.<br>
<br>
Beware of the word &quot;reliability&quot; :-)<br>
<br>
IP packets do get dropped in case of traffic congestion.  And this is likely<br>
to happen on the way out, from busy ADSL connections, or at the ISP level<br>
in case there are exceptional traffic peaks.  The less IP has to fragment,<br>
the less chances the whole message will be lost.<br>
<br>
Therefore UDP/IP is &quot;unreliable&quot;, which does not prevent most of the UDP<br>
traffic to come through, of course!<br>
<br>
Now everyone is taking care of not dropping packets unless it's absolutely<br>
necessary, due to the avalanche effect that occurs when every protocol on<br>
top of IP has to retransmit!<br>
<br>
That's probably what you meant by &quot;reliability&quot;.<br>
<br>
Raphael<br>
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