iWARP emulation protocol (was: [openib-general] RDMA connection andaddress translation API)

[Kanevsky, Arkady]

Sean,

> For the REQ to find its way to the destination, the 
> destination address must be 
> known beforehand.  We shouldn't need to pass any data in the 
> REP.  The CMA 
> passes both the source and destination address information in 
> the REQ, but only 
> uses the destination to validate against a listen request.  
> The source address 
> is passed to the user.

CM passes IB addresses of both src and dest in REQ.
How locally dest IP address is mapped to dest IB GID|LID is
defined by IPoIB.
We can request IBTA to define it also.
But the goal is to define a protocol part in IBTA. 

You are correct that if rely on CM storing the IP address of the dest
it is not needed to be passed back in REP.
If we do not need to know that response came from a different IP
address.
Or a different port.

> The slides should also discuss how to map from a TCP/IP 
> address to a service ID, 
> so that a REQ can match up with the correct listener.  The 
> approach currently 
> taken by the CMA is to use the openib OUI << 48 + TCP port number.
> 

Correct.
If we want IBTA to define a full mapping of addresses and ports then
yes.
But that does not change the protocol, it is local agreement
that must be the same on both sides of the connection.
I will include it in the next version.

Thanks,
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