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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>If you completely fill the MAC table of a switch, you’ll “turn
it into a hub” in the sense that it would start forwarding traffic out all
ports. But you still wouldn’t have collisions, because the ports would still all
be full duplex.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>If all ports are full duplex, there is no amount of traffic that
could cause collisions. Collisions can only occur on shared media and shared
media can only be half duplex. With enough traffic, you’ll start getting
dropped/delayed frames - but that’s not a collision.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>At least, that’s my take on it.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>-- <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Mike Norton<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I.T. Support<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Peace Wapiti School Division No. 76<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Helpdesk: 780-831-3080<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Direct: 780-831-3076<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'>
<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> cisco-voip-bounces@puck.nether.net
[mailto:cisco-voip-bounces@puck.nether.net] <b>On Behalf Of </b>Lelio Fulgenzi<br>
<b>Sent:</b> September-29-10 6:07 PM<br>
<b>To:</b> Matthew Ballard<br>
<b>Cc:</b> cisco-voip@puck. net<br>
<b>Subject:</b> Re: [cisco-voip] 24 port switch question<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<div>
<p class=MsoNormal>I recall a bug/exposure where one could turn a switch into a
hub by flooding the switch with arp announcements or something like that. <br>
<br>
…<o:p></o:p></p>
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<p class=MsoNormal>Don't look at me, my iPod maid that spilling mistake.<span
class=apple-style-span> </span><o:p></o:p></p>
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<p class=MsoNormal style='margin-bottom:12.0pt'><br>
On 2010-09-29, at 5:57 PM, Matthew Ballard <<a
href="mailto:mballard@otis.edu">mballard@otis.edu</a>> wrote:<o:p></o:p></p>
</div>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'>
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<p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:11.0pt;
font-family:"Calibri","sans-serif"'>On a switch with all ports running full
duplex, the collision domain is reduced down to the level of the individual
port (which is one of the key benefits of a switch), so you should never see a
collision if all ports are connected at full duplex to other switches and/or
devices.<br>
<br>
Beyond that, it depends on the switch, as you’ll hit either port capacity or
forwarding limits of the switch before anything gets dropped.<br>
<br>
Matthew Ballard<br>
Network Manager<br>
Otis College of Art and Design<br>
<a href="mailto:mballard@otis.edu">mballard@otis.edu</a><br>
<br>
<br>
On 9/29/10 1:41 PM, "Robert Shearrill" <<a
href="mailto:rshearri@uchicago.edu">rshearri@uchicago.edu</a>> wrote:</span><o:p></o:p></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:11.0pt;
font-family:"Tahoma","sans-serif"'>Hi, <br>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><br>
</span><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif"'>Can
some answer this question for me, or tell me where i can find the reading on
this question? I have looked and can find it no where.<br>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><br>
</span><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif"'>Question:<br>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><br>
</span><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif"'>How
many frames can pass through a 24-port switch simultaneouly, without causing a
collision and with using full duplex used on all ports?<br>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><br>
</span><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif"'>Thanks<br>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><br>
</span><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif"'>Robert</span><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p></o:p></span></p>
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style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>
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<p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas'>_______________________________________________<br>
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</blockquote>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'>
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<p class=MsoNormal>_______________________________________________<br>
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