1、 The Institute of Electrical and Electronics Engineers, Inc.3 Park Avenue, New York, NY 10016-5997, USACopyright 2000 by the Institute of Electrical and Electronics Engineers, Inc.All rights reserved. Published 10 March 2000. Printed in the United States of America.Print:ISBN 0-7381-1743-9 SH94755PD
2、F:ISBN 0-7381-1744-7 SS94755No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher.IEEE Std 802.5t-2000(Amendment toANSI/IEEE Std 802.5, 1998 Edition;ANSI/IEEE Std 802.5r, 1998 Edition; andANSI/
3、IEEE Std 802.5j, 1998 Edition)Information technologyTelecommunications and information exchange between systemsLocal and metropolitan area networksSpecific requirementsAmendment to Part 5: Token Ring Access Method and Physical Layer SpecificationsSponsorLAN/MAN Standards Committeeof theIEEE Computer
4、 SocietyApproved 13 January 2000IEEE-SA Standards BoardAbstract:This supplement specifies the changes required to ANSI/IEEE Std 802.5, 1998 Edition,(Base standard) and ANSI/IEEE 802.5r, 1998 Edition, and ANSI/IEEE Std 802.5j, 1998 Edition,(Amendment 1 standard) to support 100 Mbit/s Dedicated Token
5、Ring (DTR) operation. The Basestandard, together with the Amendment 1 standard, specifies shared and dedicated (point-to-point)Token Ring operation at both 4 Mbit/s and 16 Mbit/s using either the TKP Access Protocol or theTXI Access Protocol. This supplement extends Token Ring operation to 100 Mbit/
6、s for the DTR C-Port and Station using the TXI Access Protocol. Extensions to the medium access control (MAC)have been made to accommodate the requirements for high media rates (100 Mbit/s and above).Keywords:data processing interconnection, dedicated token ring, fill duplex operation, local areanet
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19、patents that are brought to its attention.Copyright 2000 IEEE. All rights reserved.iiiIntroduction(This introduction is not part of IEEE Std 802.5t-2000, Information technologyTelecommunications and informationexchange between systemsLocal and metropolitan area networksSpecific requirementsAmendment
20、 to Part 5:Token Ring Access Method and Physical Layer Specifications.)This standard is part of a family of standards for local and metropolitan area networks. The relationshipbetween this standard and other members of the family is shown below. (The numbers in the figure refer toIEEE standard numbe
21、rs.)This family of standards deals with the Physical and Data Link layers as defined by the International Organiza-tion for Standardization (ISO) Open Systems Interconnection (OSI) Basic Reference Model (ISO/IEC7498-1:1994). The access standards define seven types of medium access technologies and a
22、ssociated physi-cal media, each appropriate for particular applications or system objectives. Other types are underinvestigation.The standards defining the access technologies are as follows: IEEE Std 802Overview and Architecture.This standard provides an overview to the family of IEEE 802 Standards
23、. ANSI/IEEE Std 802.1Band 802.1kISO/IEC 15802-2LAN/MAN Management.Defines an OSI management-compatible architec-ture, and services and protocol elements for use in a LAN/MAN environment for performing remote management. ANSI/IEEE Std 802.1DISO/IEC 15802-3Media Access Control(MAC) Bridges.Specifies a
24、n architecture and protocol for the interconnection of IEEE 802 LANs below the MAC service boundary. ANSI/IEEE Std 802.1EISO/IEC 15802-4System Load Protocol.Specifies a set of services and protocol for those aspects of management concerned with the loading of systems on IEEE 802 LANs. IEEE Std 802.1
25、FCommon Definitions and Procedures for IEEE 802 Management Information ANSI/IEEE Std 802.1GISO/IEC 15802-5Remote Media Access ControlBridging . Specifies extensions for the intercon-nection, using non-LAN communication technologies, of geographically sepa-rated IEEE 802 LANs below the level of the l
26、ogical link control protocol.* Formerly IEEE Std 802.1A.DATALINKLAYERPHYSICAL802.2 LOGICAL LINK CONTROL802.1 BRIDGING802.1 MANAGEMENT802 OVERVIEW 2) Clause 3 as amended by Clause 10 for the DTR C-Port or Station supporting the 4 Mbit/s or 16 Mbit/s media speeds; 3) Clause 3 as amended by Clause 10 a
27、nd Clause 14 for the DTR C-Port or Station supporting the High Media Rate (HMR) media speeds. b) Support 48-bit addressing and use either a universally administered individual address or a locally administered individual address, as specified in 3.2.4. c) Recognize the first bit of the source addres
28、s as indication of the presence of the routing information field in the frame format defined in 3.2.5. Note that the ability to generate or respond to frames with source routing information is optional. d) Exhibit external behavior corresponding to the system timing parameters specified as follows:
29、1) Clause 3 for the Classic station supporting the 4 Mbit/s or 16 Mbit/s media speeds, and using the TKP Access Protocol; 2) Clause 3 as amended by Clause 10 for the DTR C-Port or Station supporting the 4 Mbit/s or 16 Mbit/s media speeds, and using the TKP or TXI Access Protocols; 3) Clause 3 as ame
30、nded by Clause 10 and Clause 14 for the DTR C-Port or Station supporting the HMR media speeds, and using the TXI Access Protocol. e) Exhibit external behavior corresponding to the Station Policy Flags and Variables specified as follows: 1) Clause 3 for the Classic station supporting the 4 Mbit/s or
31、16 Mbit/s media speeds, and using the TKP Access Protocol; 2) Clause 3 as amended by Clause 10 for the DTR C-Port or Station supporting the 4 Mbit/s or 16 Mbit/s media speeds, and using the TKP or TXI Access Protocols; 3) Clause 3 as amended by Clause 10 and Clause 14 for the DTR C-Port or Station s
32、upporting the HMR media speeds, and using the TXI Access Protocol. f) Implement capabilities corresponding to the Error Counters specified as follows: 1) Clause 3 for the Classic station supporting the 4 Mbit/s or 16 Mbit/s media speeds, and using the TKP Access Protocol; 2) Clause 3 as amended by C
33、lause 10 for the DTR C-Port or Station supporting the 4 Mbit/s or 16 Mbit/s media speeds, and using the TKP or TXI Access Protocols; 3) Clause 3 as amended by Clause 10 and Clause 14 for the DTR C-Port or Station supporting the HMR media speeds and using the TXI Access Protocol. g) Perform the TKP a
34、nd TXI Access Protocol functions as follows: 1) Classic Token Ring for 4 Mbit/s or 16 Mbit/s using the TKP Access Protocol operation speci-fied by the Station Operation Tables in ANSI/IEEE Std 802.5, 1998 Edition, Clause 4; 2) DTR for 4 Mbit/s or 16 Mbit/s using the TKP Access Protocol operation spe
35、cified by the Sta-tion and Port Operation Tables in ANSI/IEEE Std 802.5r, 1998 Edition, and ANSI/IEEE Std 802.5j, 1998 Edition, 9.3 through 9.6; 3) DTR for 4 Mbit/s or 16 Mbit/s using the TXI Access Protocol operation specified by the Sta-tion and Port Operation Tables in ANSI/IEEE Std 802.5r, 1998
36、Edition, and ANSI/IEEE Std 802.5j, 1998 Edition, 9.2 and 9.3; 4) DTR for the HMR using the TXI Access Protocol operation specified by the Station and Port Operation Tables in 9.2 and 9.3 in this document. 1.7 Fibre optic media conformance requirements A 4 Mbit/s, 16 Mbit/s, and 100 Mbit/s media rate
37、 implementation, claiming conformance to this part of ANSI/IEEE Std 802.5, 1998 Edition, and operating in Station or Port mode, shall meet all appropriate parameters in Clause 13. IEEE Std 802.5t-2000 LOCAL AND METROPOLITAN AREA NETWORKSAMENDMENT TO PART 5: Copyright 2000 IEEE. All rights reserved.
38、4 1.8 Local regulation The supplier of a protocol implementation that is claimed to conform to this standard shall meet local safety and environmental regulations. Annex E provides some limited guidance in this area. Replace the title of 2.2 with the following two titles to cover all types of Statio
39、ns and C-Ports: 2.2 C-Port and Station functional organization and data flow 2.2.1 4 Mbit/s and 16 Mbit/s classic Station functional organization and data flow The remainder of this clause remains unchanged. Add a new title after 2.2.1 to cover the 100 Mbit/s DTR C-Port and Station: 2.2.2 100 Mbit/s
40、 C-Port and Station functional organization and data flow Figure 2.2-1 and Figure 2.2-2 illustrate a C-Ports and Stations data flow, indicating which clauses of this standard address the various functions of a token ring C-Port or Station. Figure 2.2-1 is for a Station and C-Port connected using twi
41、sted-pair media. Figure 2.2-2 is for a Station and C-Port connected using fibre optic media. a) The PMC/PSC internal service interface (PM_UNITDATA.request; PM_UNITDATA.indication) defines the information exchange between the physical media components (PMC) specified in 9.7 and 9.8 and the physical
42、signaling components (PSC) specified in 9.8. This service interface is de-fined in 9.8. b) The PSC/MAC internal service interface (PS_UNITDATA.indication, PS_UNITDATA.request) defines the information exchange between the PSC specified in 9.8 and the MAC sublayer specified in Clause 9 and Clause 14.
43、Clause 14 defines frame formats and station facilities. Clause 9 also specifies the C-Ports Port Medium Access Control (PMAC) and Stations Station Medium Access Control (SMAC) protocol, which uses the formats and facilities defined in Clause 14 to receive and transmit information. This service inter
44、face is defined in 9.8. c) The PMAC/SMAC/PHY internal service interface (PM_STATUS.indication, PS_CONTROL.request, and PS_STATUS.indication) provides the control mechanism for the physical layer (PHY) func-tions by the MAC protocol, and the mechanism for indicating the status of the PHY functions to
45、 the MAC protocol. The PM_ STATUS.indication service interface is defined in 9.7. The PS_CONTROL.request and PS_STATUS.indication service interfaces are defined in 9.8. d) The PMAC/SMAC/LLC service interface (MA_UNITDATA.indication, MA_UNITDATA.request) is specified in ISO/IEC 15802-1 and is used as
46、 specified in 9.1. It defines the information exchange between the PMAC/SMAC sublayer and the Logical Link Control (LLC) sublayer. e) The PMAC/SMAC/Bridge service interface (M_UNITDATA.indication, M_UNITDATA.request, M_UNITDATA.response) is specified in IEEE Std 802.1d and is used as specified in 9.
47、1. It defines the information exchange between the MAC and the internal bridging sublayer. f) The PMAC/SMAC/MGT service interface (MGT_UNITDATA.indication, MGT_UNITDATA.request, MGT_CONTROL.request, MGT_STATUS.indication) defines the control mechanism of, the mechanism for indicating the status of,
48、and the information exchange between the PMAC/SMAC protocol specified in Clause 9 and the system management entity (MGT). The managed objects are specified in Clause 11. The MGT_UNITDATA.indication and MGT_UNITDATA.request primi-tives are specified in Clause 9 and are used to convey MAC management f
49、rames between the MAC and the appropriate management function (e.g., RPS, CRS, REM). IEEE TOKEN RING ACCESS METHOD AND PHYSICAL LAYER SPECIFICATION Std 802.5t-2000 Copyright 2000 IEEE. All rights reserved. 5 The PHY of the Station and C-Port consists of the PMCs, specified in 9.7 and 9.8, and the PSCs specified in 9.8. Operation over twisted pair media requires additional mandatory components. The use and availabil-ity of these components is explained in 9.7 and 9.8. PMC(9.7 and The TKP Access Protocol operating at 4 Mbit/s or 16 Mbit/s. The TKP Access Prot
