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<font size=3>At 01:17 PM 10/23/2007, Steve Wise wrote:<br><br>
<br>
<blockquote type=cite class=cite cite="">Sean Hefty wrote:<br>
<blockquote type=cite class=cite cite="">
<blockquote type=cite class=cite cite="">There has been much discussion
on a private thread regarding bug #735 - "dapltest performance tests
don't adhere to iWARP standard" that needs to move to the general
list.</blockquote>This bug would be better titled "iWarp cannot
support uDAPL API". :)<br>
Seriously, the iWarp and uDAPL specs conflict. One needs to
change.<br><br>
<blockquote type=cite class=cite cite="">Can someone come up with a
solution, possibly in iWARP CM, that will work and insure
interoperability between iWARP devices?</blockquote>I thought the
restriction was there to support switching between streaming and rdma
mode. If a connection only uses rdma mode, is the restriction
really needed at all?<br>
</blockquote><br>
Yes because all iWARP connections start out as TCP streaming mode
connections, and the MPA startup messages are sent in streaming mode.
Then the connection is transitioned into FPDU (Framed PDU) mode
using the MPA protocol.</blockquote><br>
Correct. The IETF was very clear on these requirements (significant
debate occurred over at least 12-18 months) and there is unlikely to be
any traction in changing the iWARP specifications to provide another
mechanism. Best to provide API that detect which semantics are
required and then if the application cannot adjust, then it cannot use
the iWARP semantics.<br><br>
BTW, if one uses the SDP port mapper protocol (see the IETF SDP
specification), one can detect from the start that RDMA is being used and
one could start in RDMA mode sans the MPA requirement. The
SDP port mapper protocol also enables one to apply various other policies
such as determining whether the application / remote node session should
be allowed to run over RDMA or not - simple point of control for
management. <br><br>
Mike</font></body>
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