[openib-general] RE: iWARP emulation protocol

[Kanevsky, Arkady]

Sean wrote:

> I'm not sure how much we should care about higher level 
> abstractions for this 
> discussion.  We should do what's right for IB.  Abstractions 
> that want to use IP 
> addresses can either use the standard protocol defined by the 
> IBTA or define 
> their own private data.

Correct. But we should define standard protocol suited for most apps
to avoid creations of multiple apps specific protocols.

> 
> To me, it seems that the most flexible solution is to pass 
> the source and 
> destination IP address in the CM REQ. 

I agree. This is the cleanest and most simple
to define.
But it impacts some existing apps.
That is why DAT has 64 bytes private data req.
We do not loose too many users by the time we define the complete
solution stack.


> We can then define a 
> standard mapping 
> from TCP port numbers to IB service records, or change the CM 
> version to read 
> into the private data.  What's wrong with this approach?

It is the "standard" mapping which we just spend 1 hour discussing
at SWG. What is that standard mapping if it is native IB?
IPoIB as intermediate layer? SDP as intermediate layer?
What is the standard TCP port for iSER (pick your ULP) native over RDMA
vs.
the same ULP over IPoIB?

This have to be defined. But is it part of the IP address and TCP port
info sharing between 2 sides of the connection proposal or a separate
proposal?
I think it is separate proposal but both will have to be in place
to support iWARP emulation.

Arkady





Arkady Kanevsky                       email: arkady at netapp.com
Network Appliance                     phone: 781-768-5395
375 Totten Pond Rd.                  Fax: 781-895-1195
Waltham, MA 02451-2010          central phone: 781-768-5300