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<font size=3>At 08:36 AM 9/27/2004, Roland Dreier wrote:<br>
<blockquote type=cite class=cite cite=""> Michael> I
don't follow why this is cosmetic. The SM will<br>
Michael> configure whatever number of P_Key per
port (CA or<br>
Michael> switch) that it desires. IPoverIB
does not and should<br>
Michael> not care about this. IPoverIB should
probe the SM/SA to<br>
Michael> determine what and how many P_Key it
should use. It<br>
Michael> should then establish unique interfaces
for each P_Key.<br>
Michael> This is no different than what is done for
802.1Q where a<br>
Michael> separate driver instance exists per
tag. This was our<br>
Michael> intent when we wrote the
specification.<br><br>
As far as I know the SM doesn't know anything about IPoIB.
What<br>
information can the IPoIB driver get from the SM/SA beyond what
P_Keys<br>
are assigned to its local ports? (And this is already available
from<br>
the local P_Key table)</font></blockquote><br>
The SM only knows what it configures in each port. The SA is
responsible for service management and it works with the SM to map a
given service to a P_Key. The SA also sets up the all node
multicast group. IPoverIB joins this group in order to issue ARP/ND
messages and therefore automatically discovers the P_Key to use.
IPoverIB is required to inquire what groups are available and optionally
set up event notification to be informed when groups are added for its
particular service. This eliminates the need for local P_Key
management.<br><br>
<blockquote type=cite class=cite cite=""><font size=3>By the way, it's
interesting that you mention 802.1q. The Linux implementation of
VLAN tagging requires a userspace program (vlanconfig) to be run to
create tagged interfaces.</font></blockquote><br>
In general, the IPoverIB driver should treat each new all-nodes multicast
group with a unique P_Key as a virtual hot-plug event (this was our
intent both within the IETF and in the IBTA). This should be linked
into whatever OS management interfaces are required allowing ifconfig /
dev file creation / etc. to be executed. This is orthogonal to
P_Key management which was the original point of debate earlier in this
string.<br><br>
Mike<br><br>
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