[openib-general] Re: [Rdma-developers] Meeting(07/22) summary:OpenRDMA community development discussion

[Yaron Haviv]

> -----Original Message-----
> From: Fab Tillier [mailto:ftillier at silverstorm.com]
> Sent: Monday, August 01, 2005 1:14 PM
> 
> > From: Sean Hefty [mailto:mshefty at ichips.intel.com]
> >
> > Yaron Haviv wrote:
> > > we can spend time and discuss theories and intentions, at the end
of
> the
> > > day an iWarp RNIC cannot just reside under IB-Verbs without major
> > > changes to the overall infrastructure.
> >
> > I don't disagree with having a common connection library that
supports
> both
> > IB and iWarp, or that you could derive a solution from kDAPL.  But
based
> on
> > the proposed APIs that I've seen, I believe that an RNIC could
reside
> under
> > IB verbs with minimal changes, and would likely be the best
engineered
> > solution for including RNIC support in Linux.
> 
> Just for clarity, when you say verbs you exclude connection
> establishment/management, right?
> 
> I think keeping the two distinct is important in this discussion, as
it
> seems
> there is some confusion - some people refer to verbs as verbs + CM,
others
> as
> just verbs.
> 
> Here's my take from the discussions so far:
> - RNICs can probably be made to work under the IB verbs (with changes
of
> course).
> - RNICs can probably not be made to work under the IB CM (not that
I've
> seen
> this suggested).
> 

Fab, I did the same distinction between pure verbs & the broader API
(+CM, SA, ..)

I agree that pure send, receive, .. verbs are similar with minor
differences 
And we may just want to adopt them with minor changes

On the other hand it would not be efficient to try and bend the iWarp CM
model to the IB (complex) one, but rather use a simpler one, such as the
one in DAPL that fits both camps

In IB we need to use a CM and a bunch of SA queries, where the ULP
doesn't really need all that and can do with a simple BSD like
connection request (that may map to a more complex IB or iWarp model
underneath)

There are ways in the dapl/bsd like connection mechanism enough to imply
sequrity/QoS/etc' (using a src/dst IP, network implied from IP, and
kDAPL QoS or BSD TOS, ..) so a user doesn't need direct access to SA for
connections, at the most we can add some flags to it

Yaron


> - Fab