RE: iFCP as an IP Storage Work Item

[Charles Monia <cmonia@NishanSystems.com>]

> I agree with David.  While everyone thought that iFCP is just 
> a gateway
> protocol, I do believe iFCP could be used by an HBA talking to a fibre
> channel device from an Ethernet connection.  It puts together 
> an FCP frame,
> adds a TCP/IP header, and out goes to the Ethernet wire.  

Hi Y P:

I think it's important to be clear on one thing. While a product can be
built from a common encapsulation method, it is NOT iFCP. Such a product is
basically leveraging a commmon envelope that encloses different messages.
The sender and receiver reading the contents are different entities that
speak different languages. 

In iFCP, the communicating objects are Fibre Channel storage devices and
host adapters (N_PORTS) addressed through iFCP gateways.  In FCIP, the
communicating entities are FC fabric elements hauling frame traffic
(backbone switches and FC switch elements).

Anyhow, as I stated earlier, this is a useful but somewhat speculative
conversation, since the tunneling folks have yet to be heard from on this
topic.

Charles

> -----Original Message-----
> From: Y P Cheng [mailto:ycheng@advansys.com]
> Sent: Friday, January 05, 2001 6:59 PM
> To: ips@ece.cmu.edu
> Subject: RE: iFCP as an IP Storage Work Item
> 
> 
> > Before this goes any further ... the two of you may be
> > in violent agreement.  Charles objected to a "handshake";
> > I don't think this objection would preclude one end of
> > a connection announcing the protocol that it intends to
> > use so that the other end can cleanly and quickly
> > terminate the connection if it can't or won't use
> > that protocol (ideally with an error code to the
> > other end indicating protocol incompatibility, so
> > the misconfiguration becomes obvious).  Doug's
> > suggestion of IANA-allocated numbers for identifying
> > protocols for this purpose is reasonable.
> >
> > As to the virtues of being able to speak more than
> > one protocol on a port, Fibre Channel provides examples
> > of where this sort of thing has been added after the
> > initial specifications were done, so I wouldn't dismiss
> > this out of hand.
> >
> > --David
> 
> I agree with David.  While everyone thought that iFCP is just 
> a gateway
> protocol, I do believe iFCP could be used by an HBA talking to a fibre
> channel device from an Ethernet connection.  It puts together 
> an FCP frame,
> adds a TCP/IP header, and out goes to the Ethernet wire.  
> There is good
> reason that the same HBA may talk to another fibre channel 
> device through an
> FCIP port.  There would be different ways to create these connections.
> However, many fibre channel HBAs today support multiple 
> protocols like FCP,
> IP, and VI at the same time.  Therefore, it is possible for a 
> future HBA to
> speak iFCP, FCIP, and even iSCSI on an Ethernet connection at 
> the same time.
> While I don't know if this makes economical sense, but, 
> technically, this is
> definitely possible.
>