IEEE 802 1D-2004 en Local and Metropolitan Area Networks - Media Access Control (MAC) Bridges (IEEE Computer Society)《局域网和城域网 媒体存取控制(MAC)桥接器》.pdf

1、IEEE Std 802.1D- 2004(Revision of IEEE Std 802.1D-1998)IEEE Standards802.1DTMIEEE Standard forLocal and metropolitan area networks Media Access Control (MAC) Bridges3 Park Avenue, New York, NY 10016-5997, USAIEEE Computer SocietySponsored by theLAN/MAN Standards CommitteeIEEE Standards9 June 2004Pri

2、nt: SH95213PDF: SS95213(Revision of IEEE Std 802.1D-1998) Recognized as an American National Standard (ANSI) IEEE Std 802.1DTM-2004(R2011)IEEE Standard for Local and Metropolitan Area Networks: Media Access Control (MAC) Bridges Sponsor LAN MAN Standards Committee of the IEEE Computer Society Approv

3、ed 4 June 2004 Reaffirmed 4 April 2012 American National Standard Institute Approved 9 February 2004 Reaffirmed 31 March 2011 IEEE-SA Standards Board Abstract: An architecture for the interconnection of IEEE 802 Local Area Networks (LANs) below the MAC Service boundary is defined. MAC Bridges, as sp

4、ecified by this standard, allowcommunications between end stations attached to separate LANs, each with its own separateMAC, to be transparent to logical link control (LLC) and network layer protocols, just as if thestations were attached to the same LAN. Keywords: active topology, filtering, GARP,

5、GMRP, LANs, local area networks, MAC Bridges,MAC Service, MANs, metropolitan area networks, multicast registration, transparent bridging,quality of service, RSTP, spanning tree The Institute of Electrical and Electronics Engineers, Inc. 3 Park Avenue, New York, NY 10016-5997, USA IEEE is a registere

6、d trademark in the U.S. Patent +1 978 750 8400. Permission to photocopy portions of any individual standard for educational classroom use can also be obtained through the Copyright Clearance Center. Copyright 2004 IEEE. All rights reserved.iiiIntroductionThe MAC Bridge standardization activities tha

7、t resulted in the development of IEEE Std 802.1D-1990(subsequently republished as IEEE Std 802.1D, 1993 Edition ISO/IEC 10038:1993 and IEEE Std 802.1D,1998 Edition ISO/IEC 15802-3: 1998) specified an architecture and protocol for the interconnection ofIEEE 802 LANs below the MAC Service boundary.The

8、 2004 revision of this standard incorporates two amendments into the 1998 Edition:a) IEEE Std 802.1t-2001, technical and editorial corrections to the 1998 Edition; andb) IEEE Std 802.1w-2001, Rapid Reconfiguration, which specified the Rapid Spanning Tree Algorithmand Protocol (RSTP). In addition, th

9、is revision includes further technical and editorial corrections, and removes the originalSpanning Tree Protocol (STP) as a conformance option.Relationship between IEEE Std 802.1D and IEEE Std 802.1QAnother IEEE standard, IEEE Std 802.1Q-2003, extends the concepts of MAC Bridging and filteringservic

10、es to support the definition and management of Virtual LANs (VLANs).The capabilities defined in IEEE Std 802.1Q-2003 include the definition of a VLAN frame format that isable to carry VLAN identification and user priority information over LAN technologies, such as CSMA/CD,that have no inherent capab

11、ility to signal priority information. This information is carried in an additionalheader field, known as the Tag Header, which is inserted immediately following the Destination MACAddress, and Source MAC Address (and Routing Information field, if present) of the original frame. IEEEStd 802.1Q-2003 e

12、xtends the priority handling aspects of this standard to make use of the ability of theVLAN frame format to carry user priority information end to end across any set of concatenated underlyingMACs.The VLAN Bridging specification contained in IEEE Std 802.1Q-2003 is independent of this standard, inth

13、e sense that IEEE Std 802.1Q-2003 contains its own statement of the conformance requirements forVLAN Bridges. However, IEEE Std 802.1Q-2003 makes use of many of the elements of the specificationcontained in this standard, in particulara) The Bridge architecture b) The Internal Sublayer Service, and

14、the specification of its provision by IEEE 802 LAN MACsc) The major features of the operation of the forwarding processd) The Rapid Spanning Tree Protocole) The Generic Attribute Registration Protocol (GARP)f) The GARP Multicast Registration Protocol (GMRP)Since the original Spanning Tree Protocol (

15、STP) has been removed from the 2004 revision of IEEE Std802.1D, an implementation of RSTP is required for any claim of conformance for an implementation ofIEEE Std 802.1Q-2003 that refers to the current revision of IEEE Std 802.1D unless that implementationincludes the Multiple Spanning Tree Protoco

16、l (MSTP) specified in IEEE Std 802.1Q-2003. MSTP is basedon RSTP, extended to provide support for multiple spanning trees.This introduction is not part of IEEE Std 802.1D-2004, IEEE Standard for Local andMetropolitan Area Networks: Media Access Control (MAC) Bridges.ivCopyright 2004 IEEE. All rights

17、 reserved.Notice to usersErrataErrata, if any, for this and all other standards can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/updates/errata/index.html. Users are encouraged to check this URL forerrata periodically.InterpretationsCurrent interpretations can be accessed

18、at the following URL: http:/standards.ieee.org/reading/ieee/interp/index.html.PatentsAttention is called to the possibility that implementation of this standard may require use of subject mattercovered by patent rights. By publication of this standard, no position is taken with respect to the existe

19、nce orvalidity of any patent rights in connection therewith. The IEEE shall not be responsible for identifyingpatents or patent applications for which a license may be required to implement an IEEE standard or forconducting inquiries into the legal validity or scope of those patents that are brought

20、 to its attention.ParticipantsAt the time this standard was completed, the 802.1D working group had the following membership:Tony Jeffree,Chair and EditorPaul Congdon,Vice-ChairMick Seaman,Interworking Task Group Chair and EditorLes BellPaul BottorffJim BurnsMarco CarugiDirceu CavendishArjan de Heer

21、Anush ElangovanHesham ElbakouryDavid Elie-Dit-CosaqueNorm FinnDavid FratturaGerard GoubertStephen HaddockAtsushi IwataNeil JarvisManu KayceeHal KeenBill LaneRoger LapuhLoren LarsenYannick Le GoffMarcus LeechMahalingam ManiDinesh MohanBob MoskowitzDon O ConnorDon PannellGlenn ParsonsKen PattonAllyn R

22、omanowDan RomascanuJessy V. RouyerAli SajassiDolors SalaMuneyoshi SuzukiJonathan ThatcherMichel ThorsenDennis VolpanoKarl WeberLudwig WinkelMichael D. WrightCopyright 2004 IEEE. All rights reserved.vThe following members of the balloting committee voted on this standard. Balloters may have voted for

23、approval, disapproval, or abstention. When the IEEE-SA Standards Board approved this standard on 9 February 2004, it had the followingmembership:Don Wright,Chair*Member EmeritusAlso included are the following nonvoting IEEE-SA Standards Board liaisons:Satish K. Aggarwal, NRC RepresentativeRichard De

24、Blasio, DOE RepresentativeAlan Cookson, NIST RepresentativeMichelle D. TurnerIEEE Standards Project EditorButch AntonEdward CarleyClint ChaplinSunghyun ChoiKeith ChowChristopher CookeWael DiabThomas DineenSourav DuttaClint EarlyWill FouldsDavid FratturaAnoop GhanwaniRobert M. GrowStephen HaddockJuli

25、an HoAtsushi ItoPeeya IwagoshiTony JeffreeStanley JohnsonStuart KerryShyam KaluveCees KlikKshitij KumarPi-Cheng LawRandolph LittleRyan MadronNikolai MalykhKyle MausGeorge MiaoRajesh MoorkathCharles NgetheSatoshi ObaraStephen PalmAshley PeacockSubbu PonnuswamyVikram PunjMaximilian RiegelFloyd RossMic

26、k SeamanGil ShultzAdrian StephensScott ValcourtDmitri VarsanofievMichael D. WrightOren YuenChuck Adams,Stephen BergerMark D. BowmanJoseph BruderBob DavisRoberto de BoissonJulian Forster*Judith GormanArnold M. GreenspanMark S. HalpinRaymond HapemanRichard J. HollemanRichard HulettLowell JohnsonHerman

27、n KochJoseph Koepfinger*Thomas J. McGeanSteve M. MillsDaleep MohlaPaul NikolichT. W. OlsenRonald C. PetersenGary S. RobinsonFrank StoneMalcolm V. ThadenDoug ToppingJoe D. WatsonviCopyright 2004 IEEE. All rights reserved.Contents1. Overview 11.1 Introduction 11.2 Scope 12. References 33. Definitions

28、53.1 Bridged Local Area Network.53.2 Expedited traffic. 53.3 Group . 53.4 IEEE 802 Local Area Network (LAN) 54. Abbreviations. 75. Conformance 95.1 Required capabilities 95.2 Optional capabilities 95.3 Protocol Implementation Conformance Statement.105.4 Recommendations.105.5 MAC-specific bridging me

29、thods.106. Support of the MAC Service.116.1 Support of the MAC Service.116.2 Preservation of the MAC Service 126.3 Quality of Service maintenance. 126.4 Internal Sublayer Service provided within the MAC Bridge. 166.5 Support of the Internal Sublayer Service by specific MAC procedures 196.6 Filtering

30、 services in Bridged Local Area Networks 247. Principles of Bridge operation . 297.1 Bridge operation. 297.2 Bridge architecture. 317.3 Model of operation. 327.4 Port States and the active topology 357.5 Frame reception . 357.6 Frame transmission 377.7 The Forwarding Process 377.8 The Learning Proce

31、ss. 417.9 The Filtering Database. 427.10 Spanning Tree Protocol Entity and GARP Entities . 497.11 Bridge management . 497.12 Addressing . 498. Spanning tree algorithm and protocol 579. Encoding of bridge protocol data units 599.1 Structure. 599.2 Encoding of parameter types . 59Copyright 2004 IEEE.

32、All rights reserved.vii9.3 BPDU formats and parameters 6110.GARP Multicast Registration Protocol (GMRP) 6710.1 Purpose. 6710.2 Model of operation. 6710.3 Definition of the GMRP Application. 7010.4 Conformance to GMRP .7211.Example “C” code implementation of GMRP 7512.Generic Attribute Registration P

33、rotocol (GARP). 7712.1 GARP overview. 7712.2 GARP architecture. 7912.3 Requirements to be met by GARP. 8212.4 Requirements for interoperability between GARP Participants 8312.5 Conformance to GARP Applications. 8312.6 Protocol Operation. 8412.7 State machine descriptions. 9012.8 Administrative contr

34、ols 9512.9 Procedures 9612.10 Structure and encoding of GARP Protocol Data Units 10112.11 Timer values, granularity and relationships. 10612.12 Interoperability considerations. 10613.Example “C” code implementation of GARP 10914.Bridge management 11114.1 Management functions. 11114.2 Managed objects

35、 11214.3 Data types. 11214.4 Bridge Management Entity 11314.5 MAC Entities . 11614.6 Forwarding Process 11614.7 Filtering Database 11914.8 Spanning Tree Protocol Entity. 12314.9 GARP Entities 12714.10 GMRP entities 12915.Management protocol . 13316.Bridge performance 13516.1 Guaranteed Port Filterin

36、g Rate 13516.2 Guaranteed Bridge Relaying Rate . 13517.Rapid Spanning Tree Protocol (RSTP). 13717.1 Protocol design requirements. 13717.2 Protocol support requirements . 13817.3 RSTP overview 13817.4 STP compatibility 14317.5 Spanning tree priority vectors 14317.6 Priority vector calculations 143vii

37、iCopyright 2004 IEEE. All rights reserved.17.7 Port Role assignments 14517.8 Communicating spanning tree information . 14517.9 Changing spanning tree information 14517.10 Changing Port States 14617.11 Updating learned station location information 14817.12 RSTP and point-to-point links . 15117.13 RST

38、P performance parameters 15117.14 Performance parameter management. 15317.15 Rapid Spanning Tree state machines . 15517.16 Notational conventions used in state diagrams 15517.17 State machine timers 15717.18 Per-Bridge variables. 15817.19 Per-Port variables. 15917.20 State machine conditions and par

39、ameters 16417.21 State machine procedures 16517.22 Port Timers state machine 17017.23 Port Receive state machine 17017.24 Port Protocol Migration state machine 17117.25 Bridge Detection state machine . 17117.26 Port Transmit state machine. 17217.27 Port Information state machine 17317.28 Port Role S

40、election state machine 17417.29 Port Role Transitions state machine 17417.30 Port State Transition state machine 17717.31 Topology Change state machine 17817.32 RSTP performance requirements. 17918.Bridge Detection state machine 181Annex A (normative) PICS Proforma 183A.1 Introduction 183A.2 Abbrevi

41、ations and special symbols 183A.3 Instructions for completing the PICS proforma. 184A.4 PICS proforma for IEEE Std 802.1D 186A.5 Major Capabilities 187A.6 Media Access Control Methods. 188A.7 Relay and filtering of frames . 189A.8 Basic Filtering Services . 190A.9 Addressing . 191A.10 Rapid Spanning

42、 Tree Protocol. 192A.11 BPDU Encoding. 193A.12 Implementation Parameters 193A.13 Performance . 194A.14 Bridge management . 195A.15 Remote Management 196A.16 Expedited Traffic Classes. 196A.17 Extended Filtering Services 196A.18 GMRP 197A.19 GARP. 198Copyright 2004 IEEE. All rights reserved.ixAnnex B

43、 (informative) Calculating spanning tree parameters 199Annex C (normative) Source-routing transparent bridge operation 201C.1 Overview 201C.2 Support of the MAC Service 204C.3 Principles of operation . 208C.4 Bridge management . 223C.5 Management protocol 227Annex D (normative) PICS Proforma for sou

44、rce-routing transparent bridge operation . 229D.1 Introduction 229D.2 Relay and filtering of frames . 229D.3 Bridge numbers and LAN IDs . 230D.4 Bridge management . 230Annex E (informative) Allocation of Object Identifier values 231Annex F (informative) Preserving the integrity of FCS fields in MAC

45、Bridges. 233F.1 Background 233F.2 Basic mathematical ideas behind CRC and FCS . 233F.3 Detection Lossless Circuit approach 235F.4 Algorithmic modification of an FCS . 236F.5 Conclusions 239Annex G (informative) User priorities and traffic classes241G.1 Traffic types. 241G.2 What are we managing?. 24

46、1G.3 Traffic type to traffic class mapping 242Annex H (informative) Generic Attribute Registration Protocol Design 245H.1 Use of an unconfirmed protocol 245H.2 Design of the Applicant state machine 245H.3 Design of the Registrar state machine . 246H.4 Analysis of GARP State Machine Operation. 246Ann

47、ex I (informative) Introduction of GARP, GMRP, and Extended Filtering Services. 261I.1 Migration considerations . 261I.2 Interoperability with higher-layer multicast protocols and related issues . 263Annex J (informative) RSTP Migration 265J.1 Overview of protocol changes . 265J.2 BPDU formats 265An

48、nex K (informative) Frame duplication and misordering . 267K.1 Background 267K.2 Frame duplication 267K.3 Frame misordering. 268K.4 Other considerations 269Copyright 2004 IEEE. All rights reserved. 1IEEE Standard for Local andMetropolitan Area Networks:Media Access Control (MAC) Bridges1. Overview1.

49、1 IntroductionIEEE 802 Local Area Networks (or LANs; see 3.4) of all types can be connected together using MACBridges. The Bridged Local Area Network created allows the interconnection of stations as if they wereattached to a single LAN, even if they are attached to separate LANs each with its own independent MAC. AMAC Bridge operates below the MAC Service Boundary, and is transparent to protocols operating abovethis boundary, in the Logical Link Control (LLC) sublayer or Network Layer (ISO/IEC 7498-1: 19941). Thepresence of one or more MAC Bridges can lead to differ