Storage Maintenance (storm) WG                           David L. Black
Internet Draft                                                      EMC
Intended status: Proposed Standard                       David Peterson
Expires: September 2010                                         Brocade
Updates: 4172                                             March 3, 2010

       Updates to the iFCP Protocol and Internet Protocol Number 133
                draft-ietf-storm-ifcp-ipn133-updates-01.txt


Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

   This Internet-Draft will expire on September 3, 2010.

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors. All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.




Black & Peterson      Expires September 3, 2010                [Page 1]


Internet-Draft      iFCP and Protocol 133 Updates            March 2010


   Abstract

   Changes to Fibre Channel have caused the specification of iFCP
   address translation mode to become incorrect.  Due to the absence of
   usage of iFCP address translation mode, it is deprecated by this
   document.  iFCP address transparent mode remains correctly specified.

   iFCP address transparent mode has been implemented and is in current
   use, therefore, it is not affected by this document.

   This document also records the state of Internet Protocol Number 133,
   which was allocated for a pre-standard version of FCIP.

Table of Contents


   1. Introduction...................................................2
   2. Conventions used in this document..............................3
   3. iFCP Address Translation Mode..................................3
      3.1. Problem Discussion........................................3
      3.2. Address Translation Mode Deprecation......................4
   4. Internet Protocol Number 133...................................4
   5. Security Considerations........................................4
   6. IANA Considerations............................................4
   7. Conclusions....................................................5
   8. References.....................................................5
      8.1. Normative References......................................5
      8.2. Informative References....................................5

1. Introduction

   See Section 3 of [RFC4172] for introductory material on Fibre Channel
   concepts.

   iFCP [RFC4172] operates in two modes with respect to Fibre Channel
   N_Port fabric addresses (24-bit N_Port_IDs), address transparent mode
   and address translation mode (both modes are specified in [RFC4172]):

   o  Address Transparent mode is a pass-through mode that preserves
      Fibre Channel N_Port fabric addresses.

   o  Address Translation mode is a Fibre Channel analog to Network
      Address Translation (NAT) in which iFCP gateways change Fibre
      Channel N_Port fabric addresses at the boundary between Fibre
      Channel and the Internet.   Both the source (S_ID) and destination
      (D_ID) N_Port fabric addresses may be changed by the iFCP
      gateways.


Black & Peterson      Expires September 3, 2010                [Page 2]


Internet-Draft      iFCP and Protocol 133 Updates            March 2010


   This document deprecates iFCP address translation mode because the
   specification has not tracked changes in Fibre Channel and because
   there are no known implementations.

   Internet Protocol Number 133 was allocated for a pre-standard version
   of FCIP that encapsulated FC frames directly in IP packets.  That
   protocol number is not used by the standard FCIP protocol [RFC3821]
   [FC-BB-3], but implementations of the pre-standard protocol were
   deployed.  Therefore, this document makes no change to the current
   allocation of Internet Protocol Number 133.

2. Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

3. iFCP Address Translation Mode

   iFCP address translation mode has to translate addresses embedded in
   transmitted data.  This is analogous to NAT translation of IP
   addresses embedded in IP packets.  Fibre Channel restricts the
   occurrence of embedded fabric addresses to control messages (frames);
   N_Ports send and receive two types of control frames that may contain
   embedded fabric addresses:

   o  Extended Link Services (ELSs); and

   o  FC-4 Link Services (FC-4 LSs) for the SCSI over Fibre Channel
      Protocol (FCP).

   The embedded fabric address translations for N_Port control frames
   are specified in Section 7.3 of [RFC4172].  These translations were
   correct as specified for Fibre Channel as of approximately 2003,
   based on the [FC-FS] standard for ELSs and the [FCP] standard for FCP
   FC-4 LSs.

3.1. Problem Discussion

   Significant changes have been made to FC control frames since the
   iFCP specification [RFC4172] was published; the currently applicable
   FC standards are [FC-LS] and [FCP-3], and additional changes are
   forthcoming in the [FC-LS-2] and [FCP-4] standards projects which are
   nearing completion.  These changes have caused Section 7.3 of [RFC
   4172] to become incorrect.




Black & Peterson      Expires September 3, 2010                [Page 3]


Internet-Draft      iFCP and Protocol 133 Updates            March 2010


   Actual iFCP deployment has diverged significantly from that
   anticipated during the development of [RFC4172].  All deployments of
   iFCP known to the authors of this document use address transparent
   mode for FC inter-switch links that connect E_Ports.  iFCP address
   translation mode as specified in [RFC4172] cannot be used for FC
   inter-switch links because the necessary embedded fabric address
   translations for FC inter-switch control messages (Switch Fabric
   Internal Link Services, ILSs) have not been specified.

3.2. Address Translation Mode Deprecation

   For the reasons described above, it is prudent to deprecate iFCP
   address translation mode in preference to updating it to the current
   state of Fibre Channel standards.  Updating iFCP address translation
   mode would create a continuing requirement to update an unused
   protocol mode to match ongoing changes in Fibre Channel standards.

   Therefore, this document deprecates iFCP address translation mode:

   o  iFCP address translation mode [RFC4172] SHOULD NOT be implemented
      and SHOULD NOT be used.

   o  The status of [RFC4172] remains Proposed Standard RFC in order to
      retain the specification of iFCP address transparent mode.

   o  The [RFC4172] specification of iFCP address translation mode
      should be treated as Historic [RFC2026].

4. Internet Protocol Number 133

   Internet Protocol Number 133 was allocated for a pre-standard version
   of FCIP that encapsulated FC frames directly in IP packets [IANA-IP].
   That protocol number is not used by the standard FCIP protocol
   [RFC3821], but implementations of the pre-standard protocol were
   deployed [MR].  Because use of this protocol number has been
   deployed, the protocol number needs to remain allocated.

5. Security Considerations

   The security considerations for iFCP continue to apply; see Section
   10 of [RFC4172].

6. IANA Considerations

   There are no IANA actions required by this draft.




Black & Peterson      Expires September 3, 2010                [Page 4]


Internet-Draft      iFCP and Protocol 133 Updates            March 2010


   IANA should add this document as a reference for the allocation of
   Internet Protocol Number 133, but should not change that allocation.

7. Conclusions

   For the reasons described in this document, iFCP Address Translation
   mode is deprecated, and the allocation of Internet Protocol Number
   133 remains unchanged at this time.

8. References

8.1. Normative References

   [FC-FS]  Fibre Channel Framing and Signaling Interface (FC-FS),
             ANSI INCITS 373-2003, October 2003.

   [FC-LS]  Fibre Channel - Link Services (FC-LS), ANSI INCITS 433-2007,
             July 2007.

   [FCP]    Fibre Channel Protocol (FCP), ANSI INCITS 269-1996, April
             1996.

   [FCP-3]  Fibre Channel Protocol - 3 (FCP-3), ISO/IEC 14776-223:2008,
             June 2008.

   [IANA-IP] Assigned Internet Protocol Numbers, IANA Registry,
             http://www.iana.org/assignments/protocol-numbers/protocol-
             numbers.xhtml, visited February 2010.

   [RFC2026] Bradner, S., "The Internet Standards Process -- Revision
             3", BCP 9, RFC 2026, October 1996.

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4172] Monia, C., et al, "iFCP - A Protocol for Internet Fibre
             Channel Storage Networking", RFC 4172, September 2005.

8.2. Informative References

   [FC-BB-3] Fibre Channel Backbone - 3 (FC-BB-3), ANSI INCITS 414-2006,
             July 2006.

   [FC-LS-2] Fibre Channel - Link Services - 2 (FC-LS-2), INCITS Project
             2103-D, Technical Committee T11 (www.t11.org).




Black & Peterson      Expires September 3, 2010                [Page 5]


Internet-Draft      iFCP and Protocol 133 Updates            March 2010


   [FCP-4]  Fibre Channel Protocol - 4 (FCP-4), INCITS Project 1828-D,
             Technical Committee T10 (www.t10.org).

   [MR]     Rajagopal, M., Private email communication, June 2009.

   [RFC3821] Rajagopal, M., E. Rodriguez and R. Weber, "Fibre Channel
             Over TCP/IP (FCIP)", RFC 3821, July 2004.

Acknowledgments

   The authors would like to thank Tom Talpey for helpful comments on
   this document.

   This document was prepared using 2-Word-v2.0.template.dot.

Authors' Addresses

   David L. Black
   EMC Corporation
   176 South Street
   Hopkinton, MA 01748

   Phone: +1 (508) 293-7953
   Email: black_david@emc.com

   David Peterson
   Brocade Communications
   6000 Nathan Lane North
   Plymouth, MN 55442

   Phone: +1 (612) 802-3299
   Email: david.peterson@brocade.com

















Black & Peterson      Expires September 3, 2010                [Page 6]