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<TITLE>RE: [openib-general] IPoIB IETF WG presentation updated again</TITLE>
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<P><FONT SIZE=2>> -----Original Message-----</FONT>
<BR><FONT SIZE=2>> From: Hal Rosenstock [<A HREF="mailto:halr@voltaire.com">mailto:halr@voltaire.com</A>]</FONT>
<BR><FONT SIZE=2>> Sent: Monday, August 02, 2004 8:36 PM</FONT>
<BR><FONT SIZE=2>... </FONT>
<BR><FONT SIZE=2>> Here's another update to the IPoIB presentation (MAX_ADDR_LEN slide as</FONT>
<BR><FONT SIZE=2>> pointed out by Tom).</FONT>
<BR><FONT SIZE=2> ...</FONT>
<BR><FONT SIZE=2>> -- Hal</FONT>
<BR><FONT SIZE=2>> </FONT>
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<P><FONT SIZE=2>It's good to see that MAX_ADDR_LEN has been changed to 32. Does that solve</FONT>
<BR><FONT SIZE=2>all the IPoIB ARP related problems for 2.6 kernel ? Can we store all related link</FONT>
<BR><FONT SIZE=2>information in this 32 bytes ? What is envisioned to be stored in this 32 bytes - is</FONT>
<BR><FONT SIZE=2>it just the QPN+GID, or the entire path info, or the address vector object too ?</FONT>
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<P><FONT SIZE=2>I think that ideally, if a network device can replace the ARP functionality in the kernel</FONT>
<BR><FONT SIZE=2>that'll be better. Because this way the IPoIB can get an address resolution request </FONT>
<BR><FONT SIZE=2>from the IP stack, handle it by sending an ARP, then SA query for the path record, then</FONT>
<BR><FONT SIZE=2>creation of HCA address handle, and then place it in cache and pass back this address</FONT>
<BR><FONT SIZE=2>handle. When cache is replaced or expires, IPoIB will destroy the HCA address handle.</FONT>
<BR><FONT SIZE=2>If this is not supported, then IPoIB will still need to maintain a shadow table.</FONT>
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<P><FONT SIZE=2>Beyond that, it'll be nice if we could have gotten the IP datagram without the "Ethernet"</FONT>
<BR><FONT SIZE=2>header. Currently the IPoIB driver has to chop it, and replace it with the IPoIB encapsulation</FONT>
<BR><FONT SIZE=2>header. Anyway, this is just the purity of the protocol stack layering.</FONT>
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<P><FONT SIZE=2>Dror</FONT>
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