BRIDGE COMPONENTS. Panagiotis Saltsidis

Transcription

1 BRIDGE COMPONENTS Panagiotis Saltsidis

2 Introduction A Bridge is by definition what the associated standard defines it to be and accordingly the specification text has the absolute authority in the classification of the various variant systems. Nevertheless such classification needs to follow specific and consistent taxonomy rules in order to avoid proliferation of specified systems and to enable a consistent categorization of new systems. Since support for various control and management protocols play very limited role on the current taxonomy of Bridge species this presentation will be focusing on the data plane supportive functions of each specified system in order to classify systems that need to satisfy ECMP requirements. Ethernet Public Page 2

3 MAC Service LLC MAC Service User MAC Service Provider MAC Relay Entity Media Access Method Independent Functions Media Access Method Dependent Convergence Functions MAC Service User MAC Service Provider LLC Media Access Method Specific Functions (IEEE Std 802.n) Ethernet Public Page 3

4 802.1D Bridge DA SA DU FCS Prio Ethernet Public Page 4

5 802.1D Bridge Higher Layer Entities DA SA DU Prio MAC Relay Entity DA SA DU Prio Ethernet Public Page 5 Media Access Method Specific Functions (IEEE Std 802.n)

6 Forwarding Process Ethernet Public Page 6

7 Entering the MAC Relay Higher Layer Entities DA SA DU Prio MAC Relay Entity Ethernet Public Page 7 Media Access Method Specific Functions (IEEE Std 802.n)

8 Enter Vs 802.1Q Vs allow different communities to share a physical Local Area Network infrastructure. Provide connectivity within a community but isolation between communities. Each packet carries a V tag that identifies the community to which it belongs. Ethernet Public Page 8

9 MAC Service LLC MAC Service User MAC Service Provider E MAC Relay Entity E Media Access Method Independent Functions Media Access Method Dependent Convergence Functions MAC Service User MAC Service Provider LLC Media Access Method Specific Functions (IEEE Std 802.n) Ethernet Public Page 9

10 802.1Q Bridge V Bridge V Tagging Functions DA SA DU FCS Prio Ethernet Public Page 10

11 Entering the MAC Relay Higher Layer Entities DA SA VID Prio DE Octets: 1 MAC Relay 2 Entity DU PCP E CFI E Bits: VID??-?? V Tagging Functions DU DA SA DU Prio Ethernet Public Page 11 Media Access Method Specific Functions (IEEE Std 802.n)

12 Entering the MAC Relay Higher Layer Entities DA SA PVIDPrio DE DU MAC Relay Entity E E XX-XX??-?? Tagging Functions DU Prio Ethernet Public Page 12 Media Access Method Specific Functions (IEEE Std 802.n)

13 Forwarding Process Ethernet Public Page 13

14 Forwarding Decisions V DA DA Topology not in Filtering in FDB FDB X X Ethernet Public Page 14

15 Entering the MAC Relay Higher Layer Entities DA SA VID Prio DE DU MAC Relay Entity E E V Tagging Functions V Tagging Functions Ethernet Public Page 15 Media Access Method Specific Functions (IEEE Std 802.n)

16 S-V Bridge Higher Layer Entities DA SA VID Prio DE Octets: 1 MAC Relay 2 Entity DU PCP E DEI VID E Bits: Tagging Functions??-?? 88-A8 DU DU Ethernet Public Page 16 Media Access Method Specific Functions (IEEE Std 802.n)

17 Backbone Edge Components I-component: Relay forwards/filters/learns customer addresses with S-V identifiers. Associations between customer addresses and backbone addresses stored in learned database. Is an S-V component with I-tagging functions in interface stack connecting to the Backbone Network (PIP) I-tag includes 24 bit service instance identifier and encapsulated customer addresses. MAC header containing backbone addresses added when I-tag is created. B-component: Relay forwards/fliters/learns backbone addresses with B-V identifiers Is an S-V component with I-tag specific functions in interface stack at edge of Backbone Network (CBP) Ethernet Public Page 17

18 Backbone Edge Bridge Model I-component I-BEB B-component B-BEB PIP CBP B-component Ethernet Public Page 18

19 TPMR, T-Component A TPMR component is a V-unaware Bridge component with exactly two s other than a Management Port. Supports only a subset of the functions of the Forwarding Process: Frame filtering Queuing frames Transmission selection A T-component is a TPMR with having a PIP with a single VIP (Virtual Instance Port) as one of its externally accessible ports Ethernet Public Page 19

20 Component Reserved Addresses Assignment Bridge Group Address, Nearest Customer Bridge group address IEEE MAC-specific Control Protocols group address IEEE Slow_Protocols_Multicast address Nearest non-tpmr Bridge group address IEEE MAC-specific Control Protocols group address Reserved for future standardization Reserved for future standardization Metro Ethernet Forum ELMI protocol group address Provider Bridge Group Address Reserved for future standardization Reserved for future standardization Reserved for future standardization Reserved for future standardization Provider Bridge MVRP Address Individual Scope group address, Nearest Bridge group address Reserved for future standardization Value C C C C C C C C C C C A C B C C C D C E C F Ethernet Public Page 20

21 New Bridge (ECMP) Higher Layer Entities Octets: 1 2 PCP DEI Bits: DA8 SA VID 6 Prio 5 4DE TTL Flow Hash MAC Relay Entity VID Flow?? E Flow Tagging Functions (6.22) DA SA VID Prio DE E E E??-?? 88-A8 Prio FCS DA SA V Tagging Functions (6.9) DU Ethernet Public Page 21 Media Access Method Specific Functions (IEEE Std 802.n)

22 New Bridge (ECMP) Higher Layer Entities DA SA VID Prio DE TTL Flow Hash MAC Relay Entity E Flow Tagging Functions (6.22) E DA SA VID Prio DE E E V Tagging Functions (6.9) Ethernet Public Page 22 Media Access Method Specific Functions (IEEE Std 802.n)

23 Forwarding Process Ethernet Public Page 23

24 Summary Bridge type V-unaware Bridge component Service parameters supporting MAC Relay Support for tagging functions Permanent filtering FDB entries DA, SA, Priority None C-V component Reserved TPMR component DA, SA, Priority None TPMR component Reserved T-Component DA, SA, Priority I-TAG TPMR component Reserved C-Component DA, SA, Priority, VID, DE C-V Tag C-V component Reserved S-Component DA, SA, Priority, VID, DE S-V Tag S-V component Reserved I-Component DA, SA, Priority, VID, DE S-V Tag, I-TAG S-V component Reserved Specification IEEE Std 802.1D-2004 IEEE Std 802.1D 2004, IEEE Std 802.1Q-2011, TPMR IEEE Std 802.1D 2004, IEEE Std 802.1Q-2011, T-Component IEEE Std 802.1Q-2011, C-Component IEEE Std 802.1Q-2011, S-Component IEEE Std 802.1Q-2011, I-Component B-Component DA, SA, Priority, VID, DE S-V Tag, I-TAG ECMP requirements DA, SA, Priority, VID, DE, TTL, Flow Hash S-V Tag, F-TAG S-V component Reserved IEEE Std 802.1Q-2011, B-Component Ethernet Public Page 24

25 Conclusions As currently described, ECMP support would require fundamental changes to the forwarding capabilities of the current 802.1Q complaint systems as it introduces flow based forwarding on top of the current V based forwarding. The implications of this type of change are exactly the same to the ones associated with the introduction of V based forwarding on 802.1D bridges. Ethernet Public Page 25

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