1、American National StandardDeveloped byfor Information Technology Fibre Channel Single-Byte CommandCode Sets-3 Amendment 1(FC-SB-3/AM1)ANSI INCITS 374-2003/AM1-2007ANSIINCITS374-2003/AM1-2007ANSIINCITS 374-2003/AM1-2007Supplement toANSI INCITS 374-2003American National Standardfor Information Technol
2、ogy Fibre Channel Single-Byte Command Code Sets-3Amendment 1(FC-SB-3/AM1)SecretariatInformation Technology Industry CouncilApproved September 28, 2007American National Standards Institute, Inc.AbstractThis amendment to ANSI INCITS 374-2003, Information Technology - Fibre Channel - Fibre ChannelSingl
3、e-Byte Command Set-3 (FC-SB-3), describes persistent IU pacing, a method for allowing an FC-SB-3 channel to retain a pacing count that can be used at the start of execution of a channel program.This may improve performance of long I/O programs at higher link speeds and long distances by allowingthe
4、Channel to send more IUs to the control unit and eliminating the delay of waiting for the firstCommand Response. This amendment augments, but does not replace, existing Fibre Channelstandards.Approval of an American National Standard requires review by ANSI that therequirements for due process, cons
5、ensus, and other criteria for approval havebeen met by the standards developer.Consensus is established when, in the judgement of the ANSI Board ofStandards Review, substantial agreement has been reached by directly andmaterially affected interests. Substantial agreement means much more thana simple
6、 majority, but not necessarily unanimity. Consensus requires that allviews and objections be considered, and that a concerted effort be madetowards their resolution.The use of American National Standards is completely voluntary; theirexistence does not in any respect preclude anyone, whether he has
7、approvedthe standards or not, from manufacturing, marketing, purchasing, or usingproducts, processes, or procedures not conforming to the standards.The American National Standards Institute does not develop standards andwill in no circumstances give an interpretation of any American NationalStandard
8、. Moreover, no person shall have the right or authority to issue aninterpretation of an American National Standard in the name of the AmericanNational Standards Institute. Requests for interpretations should beaddressed to the secretariat or sponsor whose name appears on the titlepage of this standa
9、rd.CAUTION NOTICE: This American National Standard may be revised orwithdrawn at any time. The procedures of the American National StandardsInstitute require that action be taken periodically to reaffirm, revise, orwithdraw this standard. Purchasers of American National Standards mayreceive current
10、information on all standards by calling or writing the AmericanNational Standards Institute.American National StandardPublished byAmerican National Standards Institute, Inc.25 West 43rd Street, New York, NY 10036Copyright 2007 by Information Technology Industry Council (ITI)All rights reserved.No pa
11、rt of this publication may be reproduced in anyform, in an electronic retrieval system or otherwise,without prior written permission of ITI, 1250 Eye Street NW, Washington, DC 20005. Printed in the United States of AmericaCAUTION: The developers of this standard have requested that holders of patent
12、s that may be re-quired for the implementation of the standard disclose such patents to the publisher. However, nei-ther the developers nor the publisher have undertaken a patent search in order to identify which, ifany, patents may apply to this standard. As of the date of publication of this stand
13、ard, followingcalls for the identification of patents that may be required for the implementation of the standard,notice of one or more such claims has been received. By publication of this standard, no positionis taken with respect to the validity of this claim or of any rights in connection therew
14、ith. The knownpatent holder(s) has (have), however, filed a statement of willingness to grant a license underthese rights on reasonable and nondiscriminatory terms and conditions to applicants desiring to ob-tain such a license. Details may be obtained from the publisher. No further patent search is
15、 con-ducted by the developer or publisher in respect to any standard it processes. No representation ismade or implied that this is the only license that may be required to avoid infringement in the use ofthis standard.iContentsPageForeword ii1 Scope 12 References 12.1 Qualification and availability
16、 of references 12.2 Approved references . 23 Definitions, abbreviations, conventions and keywords . 23.1 Definitions . 23.2 Editorial conventions . 23.3 Abbreviations, acronyms, and symbols 33.3.1 Acronyms and other abbreviations . 33.4 Keywords 34 FC-SB-3 Persistent IU Pacing 55 Replacement Clauses
17、 for FC-SB-3 . 65.1 Establish Logical Path (replacement for 6.4.2 of FC-SB-3) 65.2 Logical Path Established (replacement for 6.4.4 of FC-SB-3) 85.3 Status-Parameter Field (replacement for 8.10.3.4 of FC-SB-3) 85.4 IU Pacing (replacement for 9.1.4.5 of FC-SB-3) . 9Table1 Comparison of ISO and America
18、n numbering conventions 3AnnexA Incorporating this amendment into FC-SB-3 . 13iiForeword (This foreword is not part of American National Standard ANSI INCITS 374-2003/AM1-2007.)INCITS Fibre Channel (T11) Technical Committee (FC-TC) of Accredited StandardsCommittee INCITS developed this amendment to
19、ANSI INCITS 374-2003 during2006. The standards approval process started in 2006.Requests for interpretation, suggestions for improvement or addenda, or defectreports are welcome. They should be sent to the InterNational Committee for Infor-mation Technology (INCITS), 1250 Eye Street, NW, Suite 200,
20、Washington, DC20005.Users of this standard are encouraged to determine if there are standards in devel-opment or new versions of this standard that may extend or clarify technical infor-mation contained in this standard.This standard was processed and approved for submittal to ANSI by INCITS.Committ
21、ee approval of the standard does not necessarily imply that all committeemembers voted for its approval. At the time it approved this standard, INCITS hadthe following members:Karen Higginbottom, ChairJennifer Garner, SecretaryOrganization Represented Name of RepresentativeAIM Global Dan MullenCharl
22、es Biss (Alt.)Apple Computer, Inc. David MichaelElectronic Industries Alliance . Edward Mikoski, Jr.David Thompson (Alt.)EMC Corporation Gary RobinsonFarance, Inc. Frank FaranceTimothy Schoechle (Alt.)GS1 US Frank SharkeyJames Chronowski (Alt.)Mary Wilson (Alt.)Hewlett-Packard Company. Karen Higginb
23、ottomSteve Mills (Alt.)Scott Jameson (Alt.)IBM Corporation . Ronald F. SillettiPeter Schirling (Alt.)IEEE . Judith GormanTerry DeCourcelle (Alt.)Bill Ash (Alt.)Jodi Haasz (Alt.)Bob Labelle (Alt.)Intel. Philip WennblomDave Thewlis (Alt.)Jesse Walker (Alt.)Grace Wei (Alt.)Lexmark International. Don Wr
24、ightDwight Lewis (Alt.)Paul Menard (Alt.)Microsoft Corporation . Jim HughesDon Stanwyck (Alt.)Isabelle Valet-Harper (Alt.)National Institute of Standards b) approved and draft international standards (ISO, IEC); andc) approved foreign standards (including JIS and DIN).AMERICAN NATIONAL STANDARD ANSI
25、 INCITS 374-2003/AM1-2007American National Standardfor Information Technology Fibre Channel Single-Byte CommandCode Sets-3 Amendment 1 (FC-SB-3/AM1)ANSI INCITS 374-2003/AM1-20072For further information, contact the ANSI Customer Service Department:Phone +1 212-642-4980Fax: +1 212-302-1286Web: http:/
26、www.ansi.orgE-mail: infoansi.orgor the InterNational Committee for Information Technology Standards (INCITS):Phone 202-626-5738Web: http:/www.incits.orgE-mail: incitsitic.org2.2 Approved referencesFC-SB-3: Fibre Channel - Single-Byte Command Code Sets Mapping Protocol - 3 (FC-SB-3) ANSI INCITS374-20
27、033 Definitions, abbreviations, conventions and keywords3.1 DefinitionsThe following definition will become 3.1.20 of ANSI INCITS 374.3.1.1 Persistent IU Pacing: A method for allowing an FC-SB-3 channel to retain a pacing credit for use at the startof execution of a channel program.3.2 Editorial con
28、ventionsIn this standard, a number of conditions, mechanisms, sequences, parameters, events, states, or similar terms areprinted with the first letter of each word in upper-case and the rest lower-case (e.g., Exchange, Sequence). Anylower case uses of these words have the normal technical English me
29、anings.An alphanumeric list (e.g., a, b, c) of items indicate the items in the list are unordered. A numeric list (e.g., 1, 2, 3)of items indicate the items in the list are ordered (i.e., item 1 shall occur or complete before item 2).In case of any conflict between figures, tables, and text, the tex
30、t takes precedence. Exceptions to this conventionare indicated in the appropriate clauses.In all of the figures, tables, and text of this document, the most significant bit of a binary quantity is shown on theleft side. Exceptions to this convention are indicated in the appropriate clauses.In the va
31、rious ladder diagrams that show a sequence of events, the vertical axis (i.e., up and down the page)shows time from top to bottom.ANSI INCITS 374-2003/AM1-2007 3The ISO convention of numbering is used (i.e., the thousands and higher multiples are separated by a space). Acomma is used as the decimal
32、point. A comparison of the American and ISO conventions is shown in table 1.Numbers that are not immediately followed by lower-case b or h are decimal values (e.g., 25).A sequence of digits 0 or 1 immediately followed by lower-case b (e.g., 0101b) is a binary value. Spaces may beincluded in binary v
33、alues to delineate byte or field boundaries (e.g., 01011 010b).A sequence of digits and/or upper case letters A through F (i.e., a sequence of hexadecimal digits) immediatelyfollowed by lower-case h (e.g., FA23h) is a hexadecimal value. Spaces may be included in hexadecimal values todelineate byte o
34、r field boundaries (e.g., FD 8C FA 23h). When X or Y is used in a hexadecimal notation, it repre-sents a single hexadecimal digit.3.3 Abbreviations, acronyms, and symbols3.3.1 Acronyms and other abbreviationsCCW Channel-Command Word (see FC-SB-3)CRC Cyclic Redundancy Check (see FC-SB-3)CRR Command R
35、esponse Request (see FC-SB-3)CTC Channel-to-Channel (see FC-SB-3)DIB Device Information Block (see FC-SB-3)ELP Establish Logical Path link control IU (see FC-SB-3)FC Fibre ChannelIU Information UnitLPE Logical Path Established link control IU (see FC-SB-3)LPR Logical Path Removed link control IU (se
36、e FC-SB-3)LRJ Link level Reject link control IU (see FC-SB-3)RLP Remove Logical Path link control IU (see FC-SB-3)RV Residual count Valid (see FC-SB-3)SB-3 Single Byte protocol-3 on FC (see FC-SB-3)SYR Synchronize Response (see FC-SB-3)3.4 Keywords3.4.1 expected: Used to describe the behavior of the
37、 hardware or software in the design models assumed by thisstandard. Other hardware and software design models may also be implemented.3.4.2 invalid: Used to describe an illegal or unsupported bit, byte, word, field or code value. Receipt of an invalidbit, byte, word, field or code value shall be rep
38、orted as error.3.4.3 ignored: Used to describe a bit, byte, word, field or code value that shall not be examined by the receivingport. The bit, byte, word, field or code value has no meaning in the specified context.Table 1 - Comparison of ISO and American numbering conventionsISO American0,6 0.63,1
39、41 592 65 3.141592651 000 1,0001 323 462,9 1,323,462.9ANSI INCITS 374-2003/AM1-200743.4.4 mandatory: A keyword indicating an item that is required to be implemented as defined in this standard.3.4.5 may: A keyword that indicates flexibility of choice with no implied preference (equivalent to “may or
40、 maynot”).3.4.6 may not: A keyword that indicates flexibility of choice with no implied preference (equivalent to “may or maynot”).3.4.7 meaningful: A control field or bit that shall be applicable and that shall be interpreted by the receiver.3.4.8 not meaningful: A control field or bit that shall b
41、e ignored by the receiver.3.4.9 obsolete: A keyword indicating that an item was defined in a prior Fibre Channel standard but has beenremoved from this standard.3.4.10 optional: A keyword that describes features that are not required to be implemented by this standard.However, if an optional feature
42、 defined by this standard is implemented, then it shall be implemented as defined inthis standard.3.4.11 reserved: A keyword referring to bits, bytes, words, fields and code values that are set aside for futurestandardization. A reserved bit, byte, word or field shall be set to zero, or in accordanc
43、e with a future extension tothis standard. Recipients are not required to check reserved bits, bytes, words or fields for zero values. Receipt ofreserved code values in defined fields shall be reported as an error.3.4.12 shall: A keyword indicating a mandatory requirement. Designers are required to
44、implement all suchmandatory requirements to ensure interoperability with other products that conform to this standard. This standardprescribes no specific response by a component if it receives information that violates a mandatory behavior.3.4.13 should: A keyword indicating flexibility of choice w
45、ith a strongly preferred alternative; equivalent to thephrase “it is strongly recommended”.3.4.14 should not: A keyword indicating flexibility of choice with a strongly preferred alternative; equivalent to thephrase “it is strongly recommended not to”.3.4.15 vendor specific: Functions, code values,
46、and bits not defined by this standard and set aside for privateusage between parties using this standard.ANSI INCITS 374-2003/AM1-2007 54 FC-SB-3 Persistent IU PacingFC-SB-3 Rev 1.6 defines an IU pacing protocol that controls the number of IUs that can be in flight from a channelto a control unit. T
47、he control unit may increase the pacing count (the number of IUs allowed to be in flight fromchannel to control unit) in the first Command Response IU sent to the channel. The increased pacing count is validonly for the remainder of the current outbound exchange. In certain applications, at higher l
48、ink speeds, and at longdistances, a performance benefit is obtained by the increase in the allowed pacing count.The IU pacing protocol, as defined, has the limitation that the first burst of IUs from the channel to the control unitmay be no larger than a default value of 16. This causes a delay in t
49、he execution of channel programs with morethan 16 IUs at large distances because a round trip to the control unit is required before the remainder of the IUscan be sent by the channel, upon the receipt of the first command response, as allowed by the increased pacingcount.Persistent IU pacing is a method for allowing an FC-SB-3 channel to retain a pacing count that can be used at thestart of execution of a channel program. This may improve performance of long I/O programs at higher link speedsand long distances by allowing the Channel to send more IUs to the control unit and
