IP Storage Working Group
Internet Draft M. Krueger
M. Chadalapaka
R. Elliott
Document: draft-ietf-ips-iscsi-name-ext-00.txt Hewlett-Packard
Corp.
Expires: August 2003 February 2003
NAA naming format for iSCSI Node Names
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026 [1].
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.
Abstract
iSCSI is a SCSI transport protocol that maps the SCSI family of
protocols onto TCP/IP. This document defines an additional iSCSI
node name type format to enable use of the "Network Address
Authority" (NAA) world wide naming format used by ANSI T11 Fibre
Channel (FC) protocols.
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 RFC-2119 [2].
Table of Contents
Krueger Expires - August 2003 [Page 1]
iSCSI NAA Naming Format February 2003
1. Introduction...................................................2
2. Motivation.....................................................2
3. iSCSI Name Structure...........................................3
3.1 Type "naa." - Network Address Authority....................3
4. Terminology....................................................4
4.1 IQN........................................................4
4.2 SRP........................................................4
4.3 SAS........................................................4
4.4 NAA........................................................4
4.5 InfiniBand.................................................5
Security Considerations...........................................5
References........................................................5
Author Addresses..................................................6
1. Introduction
This document discusses the motivation for adding an NAA type format
as an iSCSI node name format and defines this format in accordance
with the iSCSI naming conventions conventions [iSCSI]. It is hoped
that defining this format would enable storage devices containing
both iSCSI and FC ports to use the same NAA-based SCSI device name..
2. Motivation
To date, there are a number of networked transports providing port
services to SCSI. These transports all incorporate some form of
world-wide unique name construction format.
SCSI transport protocol Name Format
-----------------------------------------------
| | EUI-64| NAA |IQN |
|----------------------------|-------|-----|----|
| iSCSI (Internet SCSI) | X | | X |
|----------------------------|-------|-----|----|
| FCP (Fibre Channel) | | X | |
|----------------------------|-------|-----|----|
| SAS (Serial Attached SCSI) | | X | |
|----------------------------|-------|-----|----|
| SRP (for InfiniBand) | X | | |
-----------------------------------------------
The NAA format is used by the Fibre Channel transport and the SAS
protocol made a recent decision to use NAA identifier formats. This
makes the NAA format the most commonly used identifier format for
SCSI transports. Although one of the FC-defined NAA formats contains
a mapping of EUI-64 numbers, it requires some mathematical
Krueger Expires - August 2003 [Page 2]
iSCSI NAA Naming Format February 2003
manipulation to extract the EUI-64 identifier out of this format, and
the NAA EUI-64 mapping reserves 2 bits in the EUI-64 identifier,
thereby reducing the EUI-64 namespace. If iSCSI included a naming
format that allowed direct representation of an NAA-format name, it
would facilitate construction of a target device name that translates
easily across multiple namespaces for a storage device containing
ports served by different transports.
This document proposes adding an NAA type to the iSCSI naming formats
in order to enable economy of worldwide-unique identifier assignment
for multi-transport-enabled target devices: One NAA-type SCSI device
name can be chosen for a target having SAS SCSI ports, FC SCSI ports
and iSCSI SCSI ports. [Note: Today, FCP-2 does not have a dependable
notion of SCSI device name. It is however expected that FCP-3 is
likely to incorporate the idea of a device name, or platform name,
subject to T10Æs decisions. If it does embrace the device name
notion, the same NAA format could then form the basis for targets
with SAS/FCP-3/iSCSI ports.]
In addition, there is a currently a movement in T10 to define and
report a single SCSI target device name (based on iSCSI's naming
formats), especially when the SCSI device has multiple transports
attached. This discussion arose as a result of a proposed change to
SPC-3 (T10/02-419r0: SPC-3 iSCSI device identifiers) that adds a
device name to VPD page 83 device identifier page. Addition of the
ANSI T11-defined NAA format as an allowed type for iSCSI name
creation would make the iSCSI device naming format more palatable
across all current SCSI networked transports, allowing the creation
of SCSI device names that are transport-independent. Additionally, a
single SCSI device name (regardless of transport) would allow
creation of LU names based on this SCSI device name.
The FC NAA formatted as an ASCII-hexadecimal representation has a
maximum size of 32 characters (128 bit formats) - as a result there
is no issue with this name format exceeding the maximum size for
iSCSI node names.
3. iSCSI Name Structure
In addition to the iSCSI name types of "iqn." and "eui."
type "naa." - the remainder of the string is an ANSI T10 defined
Network Address Authority identifier in ASCII-encoded
hexadecimal.
3.1 Type "naa." - Network Address Authority
Krueger Expires - August 2003 [Page 3]
iSCSI NAA Naming Format February 2003
The ANSI T10 FC-FS specification defines a format for constructing
globally unique identifiers [FC-FS] referred to as an Network Address
Authority (NAA) format.
The iSCSI name format is "naa." followed by an NAA identifier (ASCII-
encoded hexadecimal digits).
Example iSCSI name with a 64-bit NAA value:
Type NAA identifier (ASCII-encoded hexadecimal)
+--++--------------+
| || |
naa.52004567BA64678D
Example iSCSI name with a 128-bit NAA value:
Type NAA identifier (ASCII-encoded hexadecimal)
+--++------------------------------+
| || |
naa.62004567BA64678D0123456789ABCDEF
The NAA iSCSI name format might be used in an implementation where
the structure for generating FC NAA worldwide unique names is already
in place because the device contains both Fibre Channel and iSCSI
SCSI ports.
4. Terminology
4.1 IQN
iSCSI qualified name, an identifier format defined by the iSCSI
protocol [iSCSI].
4.2 SRP
SCSI RDMA Protocol. SRP defines a SCSI protocol mapping onto the
InfiniBand (tm) Architecture and/or functionally similar cluster
protocols [SRP].
4.3 SAS
Serial Attached SCSI. The Serial Attached SCSI (SAS) draft standard
contains both a physical Layer that is compatible with Serial ATA and
protocols for transporting SCSI commands to SAS devices and for
transporting ATA commands to SATA devices [SAS].
4.4 NAA
Network Address Authority - a naming format defined by the ANSI T11
Fibre Channel protocols [FC-FS].
Krueger Expires - August 2003 [Page 4]
iSCSI NAA Naming Format February 2003
4.5 InfiniBand
An I/O architecture intended to replace PCI and address high
performance server interconnect [IB].
Security Considerations
Because this document does not define any new wire protocol, there
are no additional security considerations for the iSCSI protocol.
References
Normative References
1 Bradner, S., "The Internet Standards Process -- Revision 3", BCP
9, RFC 2026, October 1996.
2 Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997
[iSCSI] Satran, J., Meth, K., Sapuntzakis, C.,Chadalapaka, M.,
Zeidner, E., "iSCSI", Internet draft (work in progress), draft-
ietf-ips-iscsi-20.txt, January 2003.
Informative References
[SAM] ANSI X3.270:1998, SCSI-3 Architecture Model (SAM).
[SPC2] NCITS.351:2001, SCSI Primary Commands - 2 (SPC-2).
[SPC3] T10/1416-D, SCSI Primary Commands - 3 (SPC-3).
[SAM2] T10/1157-D, SCSI Architecture Model - 2 (SAM-2).
[FC-FS] T11/02-018v1 - dpANS - Fibre Channel Framing and Signaling
Interface.
[IB] InfiniBand{tm} Architecture Specification, Vol. 1, Rel. 1.0.a,
InfiniBand Trade Association (www.infinibandta.org).
[SRP] INCITS.365:2002, SCSI RDMA Protocol (SRP).
[SAS] T10/1562-D, Serial Attached SCSI (SAS).
Krueger Expires - August 2003 [Page 5]
iSCSI NAA Naming Format February 2003
Author Addresses
Marjorie Krueger
Hewlett-Packard Company
8000 Foothills Blvd.
Roseville, CA 95747-5668, USA
E-mail: marjorie.krueger@hp.com
Mallikarjun Chadalapaka
Hewlett-Packard Company
8000 Foothills Blvd.
Roseville, CA 95747-5668, USA
E-mail: cbm@rose.hp.com
Rob Elliott
Hewlett-Packard Company
MC 150801
PO Box 692000
Houston, TX 77269-2000 USA
E-mail: elliott@hp.com
Krueger Expires - August 2003 [Page 6]
