T11/97-253
Project Proposal
For a New
NCITS Technical Report
FIBRE CHANNEL
PRIVATE LOOP DIRECT ATTACH
2
(FC-PLDA-2)
October 7, 1997
1 IDENTIFICATION OF PROPOSED PROJECT
1.1 TITLE: Fibre Channel Private Loop Direct Attach 2
(FC-PLDA-2)
1.2 PROPOSER
This project is proposed by Technical Committee T11.
1.3 DATE SUBMITTED: December 11, 1997
1.4 PROJECT TYPE: D - Development done within NCITS TC.
2 JUSTIFICATION OF PROPOSED TECHNICAL REPORT
2.1 NEEDS:
The Fibre Channel Arbitrated Loop (FC-AL) project defines a
general capability for FC interconnections based upon loop
topologies which can form both a part of a FC fabric, or a
complete fabric. However most of the initial implementations
use FC as a peripheral interconnect replacing existing
parallel architectures, and these are implemented as private,
isolated loops. To assist in creating these implementations,
a Private Loop Direct Attach (FC-PLDA) project was created in
T11, and is now in the final stages of approval. FC-PLDA
defines a subset of the existing FC definitions which is
appropriate for these implementations.
However, because of time-to-market pressures, the PLDA draft
has only included support for random-access block storage
devices. But there are other types of peripheral which are
also appropriate for private loop configurations, of which
perhaps the most obvious example is tape devices. In addition,
some functions which are supported by the SCSI mapping for
Fibre Channel (X3.269:1996, FCP), such as data overlay, were
also excluded from the PLDA subset because of time pressures.
The intent of this project proposal is therefore to extend the
subset defined in PLDA to cover both of these areas.
2.2 RECOMMENDED SCOPE OF TECHNICAL REPORT:
This project proposal recommends the development of a Fibre
Channel Private Loop Direct Attach (FC-PLDA-2) Technical
Report. This will contain the definition of a subset of
existing Fibre Channel definitions, and a more extensive
subset than that produced by the FC-PLDA project. This new
subset will incorporate additional functionality, including:
a) Support for peripheral types other than random-access block
storage
b) Support for additional functions already defined in
X3.269:1996, FCP, and being produced for Project 1144-D, FCP-2
2.3 EXISTING PRACTICE IN AREA OF PROPOSED TECHNICAL REPORT:
There are existing implementations of the Fibre Channel suite
of standards.
2.4 EXPECTED STABILITY OF PROPOSED TECHNICAL REPORT WITH
RESPECT TO CURRENT AND POTENTIAL TECHNOLOGICAL ADVANCES:
The architecture of Fibre Channel, as defined in FC-PH, is
based around a functional model of an interconnection fabric
and a modular definition of an interface. Because the
interface definition is based on the assumption that most
implementations will only support a subset of the defined
functionality, the interface includes a set of built-in
commands to discover which functions are implemented in each
case. Thus it is possible to define subsets for particular
markets, and have those subsets evolve and expand over time as
application requirements change. As such, the definitions
produced by this project are expected to be stable and
long-lived.
3 DESCRIPTION OF PROPOSED PROJECT
3.1 TYPE OF DOCUMENT (STANDARD OR TECHNICAL REPORT):
Technical Report
3.2 DEFINITION OF CONCEPTS AND SPECIAL TERMS: None
3.3 EXPECTED RELATIONSHIP WITH APPROVED NCITS REFERENCE
MODELS:
All Fibre Channel standards are intended for use in closed
systems.
3.4 RECOMMENDED PROGRAM OF WORK:
(1) Solicit participation by the present Fibre Channel
participants through T11 procedures and new participants through press releases. Invite comments by end-user
organizations and invite proposals from Fibre Channel
development organizations and other organizations that may
have interest in this proposed technical report.
(2) Investigate existing standards and standards projects to
determine their applicability to the development effort, and establish liaisons with other standards committees as
appropriate.
(3) Prepare a draft Technical Report based on proposals
submitted and other information gathered during the
investigations.
(4) Test the Technical Report through the voluntary and
cooperative efforts of T11 Task Group members.
(5) Submit the draft proposed Technical Report to NCITS for
further processing.
3.5 RESOURCES - INDIVIDUALS AND ORGANIZATIONS COMPETENT IN
SUBJECT MATTER:
The current membership of T11 consists of representatives from
all parts of the computer industry including semiconductor
chip manufacturers, system manufacturers and Government
agencies. Members of T11 have expressed their desire to
participate and cooperate in the development of this proposed
Technical Report.
There are sufficient resources to complete the definition of this Technical Report without delaying work on other standards
projects.
3.6 RECOMMENDED NCITS DEVELOPMENT TECHNICAL COMMITTEE:
It is recommended that this project be assigned to TC T11, in
order that the project be coordinated with work on other Fibre
Channel standards projects.
3.7 ANTICIPATED FREQUENCY AND DURATION OF MEETINGS:
This project will make use of the regularly-scheduled
bimonthly T11 plenary meetings. Informal working meetings
will be organized on an ad-hoc basis to discuss specific
subjects where appropriate.
3.8 TARGET DATE FOR INITIAL PUBLIC REVIEW (MILESTONE 4):
June, 1998.
3.9 ESTIMATED USEFUL LIFE OF TECHNICAL REPORT:
It is anticipated that this Technical Report will have a
useful life of over 10 years.
4 IMPLEMENTATION IMPACTS
4.1 IMPACT ON EXISTING USER PRACTICES AND INVESTMENTS:
The proposed technical report will provide a migration path
complementary to existing practices and investments in
peripheral interface technology. It will provide a means to
leverage user investments in that technology to new
application areas.
It is likely that isolated adverse effects would occur in any
case through non-standard evolution or revolution.
4.2 IMPACT ON SUPPLIER PRODUCTS AND SUPPORT:
The proposed technical report will provide an upward growth
path that complements and enhances existing supplier products
and support schemes. The proposed technical report will
result in expanded applications for existing and conceived
products in both the channel and network markets. It is
likely that isolated adverse effects would occur in any case
through non-standard evolution or revolution.
4.3 TECHNIQUES AND COSTS FOR CONFORMITY ASSESSMENT:
The committee will consider the results of testing provided to
the committee through the voluntary efforts of the
participants in T11. With this method all costs are borne by
the organizations of the various participants and have for the
most part been mainly an adjunct of their normal development
costs.
4.4 LEGAL CONSIDERATIONS: None known
5 CLOSELY RELATED STANDARDS ACTIVITIES
5.1 EXISTING STANDARDS:
(1) X3.230:1994, Fibre Channel Physical and Signaling Interface (FC-PH), with amendment X3.230/AM1:1996;
(2) X3.297:1997, Fibre Channel - Physical and Signaling
Interface - 2 (FC-PH-2).
5.2 NCITS STANDARDS DEVELOPMENT PROJECTS:
(1) Project 901-D for Fibre Channel - Physical and Signaling
Interface -3 (NCITS 303:199x, FC-PH-3), which has completed a
first Public Review.
5.3 NCITS STUDY GROUPS: None
5.4 OTHER RELATED DOMESTIC STANDARDS DEVELOPMENT PROJECTS:
None
5.5 ISO/IEC JTC 1 STANDARDS DEVELOPMENT PROJECTS:
No international standardization is proposed for this project.
5.6 OTHER RELATED INTERNATIONAL STANDARDS DEVELOPMENT
PROJECTS: None
5.7 RECOMMENDATIONS FOR COORDINATING LIAISON: None
5.8 RECOMMENDATIONS FOR CLOSE LIAISON: None