[openib-general] RDMA connection and address translation API

[James Lentini]

On Wed, 24 Aug 2005, Yaron Haviv wrote:

> > On Tue, 23 Aug 2005, Roland Dreier wrote:
> > 
> > > It would be possible to have another function like
> > > rdma_getpeername() that takes the transport address and returns
> > > a source IP address.  In the IB case this would do an ATS
> > > reverse lookup.  However, I hate this idea.  iSER already uses
> > > the CM private data to pass the source IP in the IB case,
> >  
> > I know this is how IB SDP works, but I don't think iSER works this
> > way.
> >
> > The code in the tree calls dat_ep_connect() with a NULL private 
> > data pointer.
> >
> > There is an iSER HELLO message described in iser_header.h contains   
> > IP addresses, but I'm not certain that this is part of the current
> > protocol (ISER_HELLO_LEN and ISER_HELLO_REPLY_LEN are unused). 
> 
> James,
> 
> iSER doesn't mandate the source IP in general since its doing a much
> stronger authentication during Login
> However we believe using a similar header to SDP can help the Passive
> side 
> a. know which destination IP was targeted (in a multi homed environment)
> b. for some implementations that want to validate the source for some
> reason
> 
> that's why the draft suggested adding the source/dst IP in the private
> data just like SDP does, 

Which draft contains this? I found

http://www.ietf.org/internet-drafts/draft-ietf-ips-iser-04.txt

but the HELLO header in section 9.3 does not contain any IP address 
information.

> I believe it can be a good idea to use the same approach for 
> NFS/RDMA and eliminate the need for reverse ATS lookup (the may have 
> some conflicts when multiple IPs exists per node). We may just use 
> the SDP hello header as is with unused fields zeroed This will allow 
> all ULPs to use the same mechanism

NFS/RDMA is not specific to iWARP or InfiniBand. My understanding is 
that this could not be easily accommodated in the current standards 
for that reason.