[openib-general] round 2 - proposal for socket basedconnection model

Kanevsky, Arkady Arkady.Kanevsky at netapp.com
Tue Oct 25 17:53:41 PDT 2005


No.
iWARP does not have to pass this info.
The info is needed for IB because ZB and SI were introduced
in IBTA 1.2 specs as optional functionality.
So if ULP wants to use that functionality it need to find
out whether remote side can support it.
This is needed for backwards compatibility.
For example iSER protocol defines the use of remote invalidate
but obviously can not be done if remote side can not support it.

I do not recall right now whether iWARP defined that functionality
as required or optional.

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
 


> -----Original Message-----
> From: Tom Tucker [mailto:tom at opengridcomputing.com] 
> Sent: Tuesday, October 25, 2005 5:56 PM
> To: Kanevsky, Arkady
> Cc: swg at infinibandta.org; openib-general at openib.org
> Subject: RE: [openib-general] round 2 - proposal for socket 
> basedconnection model
> 
> 
> Arkady:
> 
> I may actually have a constructive comment about the protocol 
> (private data format). One thing I noticed is that *almost* 
> everything in the private data header is available in the 
> native iWARP protocol header except the ZB and SI bits.  If 
> these bits become part of the canonical private data header, 
> then does that require an iWARP transport to use the header 
> too even though only two bits are useful?
> 
> Sorry if this is a dumb question,
> 
> Tom
> 
> On Tue, 2005-10-25 at 16:40 -0500, Tom Tucker wrote:
> > Arkady:
> > 
> > I don't think anyone disagrees with your goals. Unfortunately 
> > additional requirements on the implementation were coupled with the 
> > specification of the private data format (protocol). This 
> peripheral 
> > discussion derailed any attempt to discuss the protocol.
> > 
> > Attempts to separate the protocol discussion from the 
> implementation 
> > failed. And so here we are...
> > 
> > 
> > On Tue, 2005-10-25 at 15:38 -0400, Kanevsky, Arkady wrote:
> > > What are you trying to achieve?
> > > 
> > > I am trying to define an IB REQ protocol extension that 
> support IP 
> > > connection 5-tuple exchange between connection requestor and 
> > > responder. And define mapping between IP 5-tuple and IB entities.
> > > 
> > > That way ULP which was written to TCP/IP, UDP/IP, CSTP/IP (and so 
> > > on) can use RDMA transport without change. To modify ULP to know 
> > > that it runs on top of IB vs. iWARP vs. (any other RDMA 
> transport) 
> > > is bad idea. It is one thing to choose proper port to connect.
> > > Completely different to ask ULP to parse private data
> > > in transport specific way.
> > > 
> > > The same protocol must support both user level ULPs
> > > and kernel level ULPs.
> > > 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
> > >  
> > > 
> > > 
> > > > -----Original Message-----
> > > > From: Sean Hefty [mailto:mshefty at ichips.intel.com]
> > > > Sent: Tuesday, October 25, 2005 3:22 PM
> > > > To: Kanevsky, Arkady
> > > > Cc: Sean Hefty; openib-general at openib.org; swg at infinibandta.org
> > > > Subject: Re: [openib-general] round 2 - proposal for socket 
> > > > based connectionmodel
> > > > 
> > > > 
> > > > Kanevsky, Arkady wrote:
> > > > > Sean,
> > > > > answers in-line.
> > > > > Arkady
> > > > 
> > > > At this point, I'm just going to disagree with this approach
> > > > and move on with 
> > > > the current implementation of the CMA.  What's needed is a 
> > > > service that provides 
> > > > IB connections using TCP/IP addressing.  I don't believe this 
> > > > proposal meets 
> > > > this goal.
> > > > 
> > > > To meet the requirement of connecting over IB using TCP/IP
> > > > addressing, I believe 
> > > > that we need a service with a reserved service 
> identifier or range of 
> > > > identifiers, a mechanism for mapping between IP and IB 
> > > > addresses, and a 
> > > > mechanism for reversing the mapping.
> > > > 
> > > > I don't see where the proposal addresses the bulk of the work
> > > > that's required, 
> > > > nor do I think that it will present an API to the user that 
> > > > does not expose IB 
> > > > related addressing (such as service IDs).
> > > > 
> > > > - Sean
> > > > 
> > > _______________________________________________
> > > openib-general mailing list
> > > openib-general at openib.org 
> > > http://openib.org/mailman/listinfo/openib-general
> > > 
> > > To unsubscribe, please visit 
> > > http://openib.org/mailman/listinfo/openib-general
> > _______________________________________________
> > openib-general mailing list
> > openib-general at openib.org 
> > http://openib.org/mailman/listinfo/openib-general
> > 
> > To unsubscribe, please visit 
> > http://openib.org/mailman/listinfo/openib-general
> 



More information about the general mailing list