|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] unsubscribe-----Original Message----- From: John Hufferd/San Jose/IBM [mailto:hufferd@us.ibm.com] Sent: vendredi 18 aout 2000 10:03 To: ips@ece.cmu.edu Subject: RE: FC/IP vs. iSCSI & Towards Consensus on TCP Connections I agree with Kalman, and I think he stated it well. Further, we had -- I thought -- a Schedule for focus items, on which we were to concentrate. I think we are straying into distance corners, and it is not clear that this is useful. If it were possible to either separate the FC on IP stuff, or perhaps delay this discussion I think it will be very useful (Note I did not say ignore). I think we need to focus on the iSCSI protocols and refine it as we think it should be, and try to meet the direction and schedule that David Black laid out. I understand that some folks want to have many TCP connections to a storage entity, including at least one TCP/IP connection per LUNs. I think it has been agreed by Julian that iSCSI will support that, with some extensions which he suggested. Even though most folks will not implement their Storage Controllers in that manor, I think that issue is perhaps settled. Julian could perhaps restate the change that would make the TCP per LUN folks (if more then one) happy. This may permit us to really move off of point "A" (specified by David Black as "Should iSCSI require a TCP connection per LUN?"). If that is so, then I also submit that we have not been focusing enough time on point "B" ("Should iSCSI have a session abstraction that binds multiple TCP connections into one iSCSI connection? "). I would like to hear from folks that believe that iSCSI does not support any number of conversations per session. I say this because I thought iSCSI could support one or more TCP/IP connections per session. Therefore, the various implementers can decide on what they will support -- one, or more then one, compatibly with any other implementations since one connection per session is the default. I say default since the target can refuse or accept more then one connection per session. So I would like to understand if this is acceptable -- especially since as we have seen that working group have both positions represented (one & more then one). I think that it might be correct that the current spec satisfies the need enough to say that point "B" has been addressed. . . John L. Hufferd meth@il.ibm.com@ece.cmu.edu on 08/18/2000 12:03:49 AM Sent by: owner-ips@ece.cmu.edu To: ips@ece.cmu.edu cc: Subject: RE: FC/IP vs. iSCSI Doug wrote: "In reality, the iSCSI proposal was to a be a modification for a Fibre-Channel controller. A complete and unaltered encapsulation is the most straightforward approach and likely with the lowest overhead and risk." This is not correct. The original iSCSI proposal was meant (at least by some of the authors) to provide a SAM-2 compliant native transport for SCSI over (specifically) TCP. The ultimate goal is to have a single network infrastructure for regular internet traffic and for storage traffic; i.e. the ultimate goal is to not need a separate Fibre-Channel infrastructure. (Sorry Fibre-Channel fans ;-).) The same management tools and off-the-shelf components can then be used for both ordinary internet infrastructure and for remote storage infrastructure. Now the IP Storage WG charter is broader than what iSCSI provides. There is no need for iSCSI to provide a universal solution to all IP storage problems. Let's develop the iSCSI protocol to do well what it was originally designed for: native SCSI over TCP. We have to keep in mind, however, that in order for iSCSI to be adopted, we will probably have to provide some support for existing storage SAN infrastructure (i.e. Fibre Channel) bridging. There is no need, however, to make that the primary focus of the iSCSI protocol. - Kalman
Home Last updated: Thu Jan 24 13:17:54 2002 8453 messages in chronological order |