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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Official IPS Orlando interim minutesIPW Working Group Orlando Interim Meeting Minutes, January 16-17, 2001 ---------------------------------------------------- These minutes report conclusions reached at the meeting with comments on subsequent action on the mailing list where appropriate. -- iSCSI and related items (January 16th, plus about an hour on the morning of January 17th) (1) Framing - The iSCSI draft will be revised to add a formal iSCSI interface to framing - This will support the current marker approach, SCTP, and SCTP-like chunking for TCP. - The existing description of markers will be moved to an appendix as an example. -The WARP group working on RDMA will write a draft on using SCTP-like chunking for iSCSI without RDMA (2) Error Recovery - Terminology Changes - "Reference Number" and "RN" are used only for SCSI -iSCSI uses "Sequence Number" and "SN" instead - "AER" is used only for SCSI - iSCSI communication of asynchronous events is through a mechanism that is now called "Asynchronous Messages" - iSCSI uses these to implement AER - If a SCSI initiator has disabled AER, iSCSI does not send the corresponding Asynchronous Messages, but may still send iSCSI to iSCSI Asynchronous Messages that do not cause AER events visible to SCSI. - CmdSN (formerly CmdRN) is mandatory in all cases to simplify things. - This includes single connection sessions - SCSI has defined a new (optional) SCSI Command Ref Number - iSCSI will use byte #2 in the iSCSI header (currently Reserved) to transport the SCSI CRN when it is present. - This is not the ideal solution, but matches the level of support in FCP. - SCSI uses a transport-specific mode page to negotiate CRN usage, therefore iSCSI will use a text key to handle this negotiation (updated based on investigation after the meeting). - DataSN (formerly DataRN) functionality will be removed. Error recovery is now at the granularity of commands, not within a command. - There will be a significant connection recovery write-up, including details, procedures and examples added to the draft. - Ping/NOP issues - A description of intended usage will be added to the draft as advice to implementers. - A ping is intended to check whether the corresponding protocol is alive - NOP responses are not permitted to request further responses in order to avoid NOP loops - Abort WARNING will be added to the draft. - Immediate Delivery of Aborts and similar task management commands may have unexpected results when multiple TCP connections are in use in a single iSCSI session because Abort, Clear Task Set, etc. may bypass command(s) to be aborted/cleared on other TCP connections. - Ordered Delivery should be used instead when this is a concern. (3) CRC - [[iSCSI will use separate CRCs on header and data to make header modification easier for systems that need to do that.]] NOTE: This meeting conclusion was *rejected* on the mailing list and hence remains an open issue. - Using the same CRC algorithm on header and data is simpler - in particular the idea of using a 16-bit CRC on the header was discarded. NOTE: This conclusion to not use 16-bit CRC algorithms remains the WG consensus. - One CRC should cover both the fixed header and optional extensions. NOTE: This is part of the separate CRCs conclusion that was rejected on the list, and hence this issue is open. - Sense of the room on CRC Algorithms - CRC-32 is the obvious first/default choice. - There is some interest in investigating both weaker (Adler-32) and stronger (CRC-64) CRCs (CRC-64 may not be appropriate for header, and is still a research topic). - CRCs are MUST implement - Open issue: whether CRC use is negotiable - Default: Use CRCs - Limiting the amount of data per CRC - Probability of undetected error rises with amount of data covered by one CRC. - There will be at most one data CRC per PDU - This limit SHOULD be enforced limit by fragmenting large data blocks into Multiple Data PDUs - Julian Satran will look for the reference that suggests CRC-32 should not be used on data blocks significantly larger than about 8-10k. (4) Security - Current iSCSI security digests will be removed in favor of IPsec and/or TLS - Only reason for digests is data integrity (i.e., CRCs) - Open issue: How does iSCSI negotiate or detect presence of lower level security? - Open issue: What is minimum security required to be used (authentication/integrity) by IETF? Resolution: IETF requires implementation of strong security sufficient for public networks, but permits negotiation down to weaker (or even no security), *provided that* the negotiation is secure (e.g., against man in the middle attack to force negotiation of "no security". - SRP and Kerberos login authentication will remain in the iSCSI draft. (5) Naming - UTF-8 will be used instead of ASCII for text strings in iSCSI login and text commands, naming, discovery, etc. - Binary values will be translated to text strings [further discussion on the list indicated a preference for hex (0xnnn format) and decimal representations] and encoded in UTF-8 rather than adding type/length support to send them natively. - Localization of iSCSI text is forbidden on the wire for interoperability reasons (e.g., keys/values in login and text commands are the same byte strings, no matter what the locale). -- FCIP and related items (January 17th) 1) Ralph Weber verbally presented some changes to the FCIP draft, specifically dealing with framing, header and timestamps. A formal proposal, in the form of a draft, has been submitted in mid-February. 2) SOF/EOF encodings. The current draft uses the same SOF/EOF encodings as are in the FC-BB specification. While that draft lists a number of encodings, only a subset are required by that document. Discussions about the various encodings have lead to the conclusion that the subset should be the only SOF/EOF encodings specified in the FCIP document. That subset is restricted to class 2 and class 3 support. The other encodings are either not defined in FC-FS (framing and signaling), are Class 1 specific (which is not currently used in the industry) or class 4 (which is not yet defined). 3) Figure 4 in the document needs to be updated. It currently implies that the FC header will immediately follow the TCP header. Misleading, in that it appears to be at a fixed offset and does not indicate that optional TCP headers may be in place between the TCP and FC headers. In particular, put a box with ellipses in it to make this clearer. 4) David Black provided input on QoS (David is a coauthor of the Differentiated Services header and architecture RFCs). The FCIP draft should be revised to avoid specifying a specific Differentiated Services Code Point (DSCP) and should instead specify expected/required performance criteria. 5) Error recovery is still a major issue in the current specification, in particular the handling of the FC and TCP timeouts and their correlation. Ralph Weber's discussion earlier in the session applicable here. We really need more input on this from the FC switch vendors. This will be discussed in the FC-BB2 meeting at T11 to solicit their input. 6) Security -- Authentication a must. IPSec and TLS are the logical choices here. TLS may be the better choice of the two. iSCSI facing the same issues. FCIP should take iSCSI decisions/considerations into account and try to align with iSCSI if possible. 7) Clarification needed to the document indicating that E_Ports are supported by this document. While not prohibited by the current document, not clear that this is supported either. IETF IP Storage (ips) WG Interim Meeting Attendees Orlando, Florida - January 16, 2001 ----------------------------------- David Black black_david@emc.com John Hufferd hufferd@us.ibm.com Jack Harwood jharwood@emc.com David Peterson dap@cisco.com Julian Satran Julian_Satran@il.ibm.com Costa Sapuntzakis csapuntz@cisco.com Steve DeGroote sdegroote@cisco.com Mark Bakke mbakke@cisco.com Naoki Watanabe naoki.wtanabe@hds.com Neil Wanamaker ntw@crossroads.com Donald Getty donald_getty@ti.com Larry Lamers LJLAMERS@ieee.org Jim Hafner hafner@almaden.ibm.com Bob Nixon bob.nixon@emulex.com Ken Moe kenneth.moe@sun.com Mark Edwards medwards@eurologic.com Wayland Jeong wayland@troikanetworks.com Bill Terrell terrell@troikanetworks.com Bob Snively rsnively@brocade.com Ralph Weber roweber@acm.org Stephen Ostrowski sostrowski@giganet.com Jim Williams jimw@giganet.com Mike Mesnier michael.mesnier@intel.com Randy Haagens randy_haagens@hp.com Bill Lynn bill-lynn@corp.adaptec.com Rob Haydt robhay@microsoft.com Vit Novak vit.novak@sun.com Albert Chang albert.chang@compaq.com Roger Cummings roger.cummings@veritas.com Howard Hall howard@pirus.com John Scheible Dal Allan Mike Fitzpatrick mfitzpatrick@fcpa.fujitsu.com Jon Sreekanth jon.sreekanth@trebia.com Elizabeth Rodriguez egrodriguez@lucent.com Joe Steinmetz joe_steinmetz@agilent.com Matt Wakeley matt_wakeley@agilent.com Luciano Dalle Ore luciano.dalle.ore@quantum.com Kevin Gibbons kgibbons@nishansystems.com Josh Tseng jtseng@nishansystems.com Charles Monia cmonia@nishansystems.com Henry Yang Henry.Yang@mcdata.com Paul Congdon paul_congdon@hp.com Vi Chau vchau@gadzoox.com Gaby Hecht ghecht@gadzoox.com Pierre Labat pierre_labat@hp.com James Pinkerton jpink@microsoft.com Terry Gibbons terry.gibbons@lsil.com Craig Carlson cwc@ancor.com John Vrabel j.vrabel@san.com Somesh Gupta somesh_gupta@ieee.org IETF IP Storage (ips) WG Interim Meeting Attendees Orlando, Florida - January 17, 2001 ----------------------------------- Elizabeth Rodriguez egrodriguez@lucent.com David Black black_david@emc.com Murali Rajgopal muralir@lightsand.com Craig Carlson craig.carlson@qlogic.com David Peterson dap@cisco.com Josh Tseng jtseng@nishansystems.com Kevin Gibbons kgibbons@nishansystems.com John Vrabel j.vrabel@san.com Albert Chang albert.chang@compaq.com Bob Nixon bob.nixon@emulex.com Jon Sreekanth jon.sreekanth@trebia.com Mike Fitzpatrick mfitzpatrick@fcpa.fujitsu.com Donald Getty donald_getty@ti.com Jack Harwood jharwood@emc.com Wayland Jeong wayland@troikanetworks.com Mark Edwards medwards@eurologic.com Henry Yang Henry.Yang@mcdata.com Paul Congdon paul_congdon@hp.com Steve Degroote sdegroote@cisco.com Vi Chau vchau@gadzoox.com Gaby Hecht ghecht@gadzoox.com Venkat Rangan venkat@rhapsodynetworks.com Howard Hall howard@pirus.com Larry Lamers LJLAMERS@ieee.org Lucian Dalle Ore Luciano.Dalle.Ore@quantum.com
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