IEEE 802.1ah Issues Paul Bottorff, Mark Holness, Michael Chen, Dinesh Mohan, Glenn Parsons January 10, 2005 Sacramento.

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Transcript IEEE 802.1ah Issues Paul Bottorff, Mark Holness, Michael Chen, Dinesh Mohan, Glenn Parsons January 10, 2005 Sacramento.

IEEE 802.1ah Issues

Paul Bottorff, Mark Holness, Michael Chen, Dinesh Mohan, Glenn Parsons January 10, 2005 Sacramento

Agenda

> Introduction > Terminology

• Terminology in agreement • Terminology needing consistent use

> Frame Format

• Basic Format Primatives in agreement • Extended Service VLAN ID address size • OAM Frames & Format Variations

> “Baggy pants” and peer reference model

P802.1ah - Provider Backbone Bridges

Task Force 05 Proposals TF ballot 06 WG ballot Sponsor ballot 07 Standard!

N D J F M A M J J A S O N D J F M A M J J A S N D J F M A M

PAR D1.0

D1.5

Legend

802 Plenary 802.1 Interim IEEE-SA Standards Board

D2.0

D2.5

D3.0

D4.0

IEEE 802.1ah (Provider Backbone Bridge) Context

Provider Backbone Bridge 802.1ad

Interfaces Provider Bridge Network (802.1ad) Network (802.1ah) Provider Bridge Network (802.1ad) 802.1aj

Provider Bridge Network (802.1ad) CFM(802.1ag) Runs End-to-end MRP(802.1ak) Runs in 802.1ad & 802.1ah

Provider Backbone Bridge Network (PBBN)

PB PBB PB PBB PB PB PBB PBB

• •

: Provider Bridge (as defined by 802.1ad)

PBB

: Provider Backbone Bridge Edge (as defined by 802.1ah)

Provider Network Example

Customer Equipment Provider Bridged Network Provider Backbone Bridged Network CE CE CE CE C C C C PB PB PEB A A A A P PB P P PB P PB P P P PB PB P PB D D B PBB B B PBB B PB B B B PBB B PBB D D 7 Legend: C Customer LAN PBB Provider Backbone Bridge A Access LAN PEB P Provider LAN Provider Edge Bridge D Boundary LAN B Backbone LAN Provider Network Port CE Customer Equipment Customer Network Port PB Provider Bridge

PBBN Provides Multi-Point tunnels between PBNs PBN PBN

B-VLAN X PBB

S-VLAN 4

BBN PBB PBB

S-VLAN 3

PBB

PBN

PBB PBB

PBN S-VLAN 2

B-VLAN

Y S-VLAN 1 •

BB PB

: Provider Backbone Bridge Edge • • Each B-VLAN carries many S-VLANs S-VLANs may be carried on a subset of a B-VLAN (i.e. all P-P S-VLANs could be carried on a single MP B-VLAN providing connection to all end points.

Agenda

> Introduction > Terminology

• Terminology in agreement • Terminology needing consistent use

> Frame Format

• Basic Format Primatives in agreement • Extended Service VLAN ID address size • OAM Frames & Format Variations

> “Baggy pants” and peer reference model

Terminology

> IEEE 802.1ad Terminology • C-TAG • C-VLAN Customer VLAN TAG Customer VLAN • C-VID • S-TAG • S-VLAN • S-VID Customer VLAN ID Service VLAN TAG Service VLAN Service VLAN ID > Additional Provider Backbone Bridge Terminology • XS-TAG • XS-VID Extended Service VLAN TAG (I-TAG/ES-TAG) Extended Service VLAN ID (SID/ES-VID) • C-MAC • B-MAC • B-VLAN Customer MAC Address Backbone MAC Address Backbone VLAN (tunnel) • B-TAG • B-VID Backbone TAG Field Backbone VLAN ID (tunnel)

Extended Service Tag

> Extended Service Tag is the field added in the PBB Encapsulation which carries the Extended VLAN ID.

> Proposed names are: • ES-TAG for Extended S-TAG • I-TAG for Service ID TAG • XS-TAG for Extended S-TAG > Comments: • ES-TAG can be confused with End Station • XS-TAG is longer than I-TAG • XS-TAG could be shortened to X-TAG > Proposal: • Agree on one of I-TAG or X-TAG so we can have consistent presentations

Extended Service VLAN

> Extended Service VLAN is the larger VLAN ID used to carry the S-VID over a Provider Backbone Bridge Network > Proposed names are: • ES-VID for Extended Service VLAN ID • SID for Service ID • XS-VID for Extended Service VLAN ID > Comments: • ES-VID can be confused with End Station • SID does not have clear VLAN definition • XS-VID can be shortened to X-VID • XS-VID is longer than X-VID • Another option would be to use I-VID for consistency with I-TAG > Proposal: • Agree on one of I-VID or X-VID

Agenda

> Introduction > Terminology

• Terminology in agreement • Terminology needing consistent use

> Frame Encapsulation Format

• Basic Format Primatives in agreement • Extended Service VLAN ID address size • OAM Frames & Format Variations

> “Baggy pants” and peer reference model

802.1ah Encapsulation Format

• • • 802.1ah Bridges encapsule frames with a BBN header 802.1ah header contains a) Extended Service VLAN identifier (I-VID) − − Identifies the Provider Bridge S-VLAN within the BBN Is carried within an I-TAG which is 32 bits long and identified by an 802.1ah Ethertype − − Requires at least 2^20 bits to identify 1M services Proposals for 2^20, 2^24, and 2^28 bits b) Site Connectivity identifier (B-VID) − Identifies a B-VLAN (or tunnel) that is used to transport the BBN S-VLANs − − Site connectivity (i.e., tunnel) can be point-to-point or multi-point in nature B-VLAN is carried in a B-TAG with the 802.1ad Ethertype and S-TAG format c) Backbone POP Address (B-MAC) MAC Address for POPs within Site Connectivity 802.1ad Service VLAN IDs (S-VIDs) map to 802.1ah Extended Service VLAN IDs (I-VIDs) − − PBN S-VIDs are local to the PBN BBN I-VIDs are local to the BBN 14

Encapsulation Frame Header

1 2 3 4 2 6 10 14 18 22 26 30 32

Backbone Destination Address Backbone Source Address .1ad Ethertype .1ad B-TAG TCI .1ah Ethertype .1ah I-TAG TCI Encapsuled Destination Address Encapsuled Source Address B-DA B-SA B-TAG I-TAG

• The B-TAG is identical to and S-TAG and optional in the frame 15

Extended Service VLAN ID Size

20 Bit I-VID 24 Bit I-VID 28 Bit I-VID Octets 1 Reserved Bits 8 1 8 2 PRE/DE 4 3 Octets 1 Rsv Bits 8 4 3 PRE/DE 1 3 2 Octets 1 PRE/DE Bits 8 4 3 2 Rsv - Reserved PRE/DE – Priority/Drop Eligible I-VID – Extended Service VLAN ID 3 3 3 I-VID I-VID I-VID 4 4 4 1 1 1

I-VID Size Considerations

> 20 bit format is similar to MPLS label where EXP/S bits are replaced with PRE/DE and TTL field is reserved > 20 bit format may be short sighted. Residential applications will increase the service demand by 10X. 20 bits allows 1 million S-VLAN, however we could have more.

> The I-VID is not a label. The I-VID limits the number of S-VLANs in a backbone region rather than link (as in a label).

> Having 8 reserved bits leaves a lot open to abuse.

> The 24 bit format provides more address space for residential and sparse address usage > The 28 bit format takes up all the extra bits > Recommendation: Assign 28 bits for I-VID for first draft. If we need some additional control bits we can shrink the I-VID as needed placing the control bits in the high order area. This will result in a I-TAG TCI with no un-used bits and give the maximum possible I-VID address size.

OAM Frame Header

1 2 3 4 2 6 10 14 18 22 26

Backbone Destination Address Backbone Source Address .1ad S-TAG TCI .1ad Ethertype .1ag Ethertype Version, ME Level, OpCode, HeaderLen Transaction ID/ Sequence #

Agenda

> Introduction > Terminology

• Terminology in agreement • Terminology needing consistent use

> Frame Encapsulation Format

• Basic Format Primatives in agreement • Extended Service VLAN ID address size • OAM Frames & Format Variations

> “Baggy pants” and peer reference model

Dual Relay PBB Model

BB Topology Element PB PEER BB PEER EISS ISS CFM UP CFM DOWN .1Q “Y” PB Topology Element CFM UP CFM UP CFM DOWN .1Q “Y” PBB SHIM CFM DOWN .1Q “Y” CFM UP CFM DOWN .1Q “Y” MAC BB LAN PB LAN MAC

PBB Shim Functions

MIF

802.1ad

Relay MIF BB MCF MCF MIF

802.1ad

Relay MIF MCF PBB Shim MAC (802.3) Virtual MAC

Backbone Edge

PB MCF MAC (802.3) > > > > Does encap/decap of 802.1ad frame Maps S-VID from 802.1ad into larger Extended Service VID (XS-VID) Learns and Correlates Backbone POP and Customer MAC addresses Filters L2 control packets sourced by core relays or by provider bridge relays (divides spanning trees)

PBB Peer Model

Provider Bridge Network PB PBI Backbone Edge MIF 8.5,6.7,9.5

Relay MIF 8.5,6.7,9.5

MCF (D 6.5) MAC (802.3) PBB SHIM MIF Relay MIF MCF Imaginary MAC MCF MAC (802.3) Backbone Core MIF Relay MIF MCF MAC (802.3) MCF MAC (802.3) Backbone Edge MIF Relay MIF MCF MAC (802.3) MCF MIF 8.5,6.7,9.5

Relay MIF 8.5,6.7,9.5

PBB SHIM Imaginary MAC MCF (D 6.5) MAC (802.3) Provider Bridge Network PBI PB

PB PBB PBB PB PB PBB PBB PB

Single Relay Outside PBB Shim Model

CFM UP CFM UP CFM UP CFM UP CFM DOWN .1Q “Y” MAC BB LAN CFM DOWN .1Q “Y” MAC CFM DOWN .1Q “Y” PBB SHIM MAC CFM DOWN .1Q “Y” PB LAN MAC

Single Relay Inside PBB Shim Model

CFM UP CFM DOWN .1Q “Y” MAC BB LAN CFM UP CFM DOWN .1Q “Y” PBB SHIM MAC MAC CFM UP CFM DOWN .1Q “Y” CFM UP CFM DOWN .1Q “Y” MAC PB LAN

Backup Slides

802.1ah PAR

> > > > > > > >

1. ASSIGNED PROJECT NUMBER:

802.1ah

2. SPONSOR DATE OF REQUEST:

2004-10-07

3. TYPE OF DOCUMENT:

Standard

4. TITLE OF DOCUMENT:

Standard for Local and Metropolitan Area Networks – Virtual Bridged Local Area Networks - Amendment 6: Provider Backbone Bridges

5. LIFE CYCLE:

Full-Use

6. TYPE OF PROJECT:

Amendment P802.1Q

11. TYPE OF SPONSOR BALLOT:

Individual Expected Date of Submission for Initial Sponsor Ballot: 2006-12-31

12. PROJECTED COMPLETION DATE FOR SUBMITTAL TO REVCOM:

2007-09-31

Scope

The scope of this standard is to define an architecture and bridge protocols compatible and interoperable with Provider Bridged(1) Network protocols and equipment allowing interconnection of multiple Provider Bridged Networks, to allow scaling to at least 2^20 Service Virtual LANs, and to support management including SNMP.

Completion of this document contingent? Yes 1)This standard is designed to support Provider Bridges (IEEE P802.1ad).

Purpose & Reason

Purpose: This standard will complete the future work identified by P802.1ad, by providing a specific means for interconnecting Provider Bridged Networks. It will enable a Service Provider to scale the number of Service VLANs in a Provider Network by interconnecting the Service VLANs, and provide for interoperability and consistent standards based management.

Reason: This project is intended to facilitate the scaling of Provider Bridged P802.1ad networks using existing Bridged and Virtual Bridged LAN technologies. Despite user demand and initial deployment of LAN-based backbones for connecting P802.1ad networks, there is currently no interoperability between different vendors, nor a coherent management framework for different techniques. Most major carriers, who will be the users of this standard, are currently deploying LAN-based service networks that need to be scaled to meet the demands both of transition from existing leased line service and expansion of multipoint services.

Broad Market Potential

A standards project authorized by IEEE 802 shall have a broad market potential. Specifically, it shall have the potential for: a) Broad sets of applicability. b) Multiple vendors and numerous users. c) Balanced costs (LAN versus attached stations). This project is intended to facilitate the scaling of Provider Bridged P802.1ad networks using existing Bridged and Virtual Bridged LAN technologies. Despite user demand and initial deployment of LAN based backbones for connecting P802.1ad networks, there is currently no interoperability between different vendors, nor a coherent management framework for different techniques. Most major carriers are currently deploying LAN-based service networks which need to be scaled to meet the demands both of transition from existing leased line service and expansion of multipoint services. The costs related to this technology should be broadly similar to those of existing Bridging technology based on 802.1D/802.1w/802.1Q/802.1s.

Compatibility

IEEE 802 defines a family of standards. All standards shall be in conformance with the IEEE 802.1 Architecture, Management and Interworking documents as follows: 802. Overview and Architecture, 802.1D, 802.1Q, and parts of 802.1f. If any variances in conformance emerge, they shall be thoroughly disclosed and reviewed with 802. Each standard in the IEEE 802 family of standards shall include a definition of managed objects which are compatible with systems management standards. This standard will be compatible with 802.1Q as amended by P802.1ad and P802.1ag. This project will be compatible with existing 802.1 Architecture, Management and Interworking standards. The Provider Backbone Bridge will rely on extensions to 802.3 frame size for additional header space. Work on frame size extension is currently under study at 802.3.

Distinct Identity

Each IEEE 802 standard shall have a distinct identity. To achieve this, each authorized project shall be: a) Substantially different from other IEEE 802 standards. b) One unique solution per problem (not two solutions to a problem). c) Easy for the document reader to select the relevant specification. There is no other IEEE standard or project that allows scaling of a Provider Bridge network to support large numbers of Service VLANs. No existing solution provides a multipoint LAN backbone for interconnection of Provider Bridges. The document reader will have an easy reference to scaling of Provider Bridge networks.

Technical Feasibility

For a project to be authorized, it shall be able to show its technical feasibility. At a minimum, the proposed project shall show: a) Demonstrated system feasibility. b) Proven technology, reasonable testing. c) Confidence in reliability. The proposed standard will be based on existing, proven, standardized, Bridged LAN and Virtual Bridged LAN technology. These technologies are widely implemented and highly reliable.

Economic Feasibility

For a project to be authorized, it shall be able to show economic feasibility (so far as can reasonably be estimated), for its intended applications. At a minimum, the proposed project shall show: a) Known cost factors, reliable data. b) Reasonable cost for performance. c) Consideration of installation costs. The technology that will be developed in the proposed standard will not differ significantly from the economic factors associated with existing Bridged LAN and Virtual Bridged LAN technologies. The cost factors for Virtual Bridged LAN technology are favorable when compared to existing provider networks based on MPLS or SONET.

A Provider Bridge Scaling Solution “Provider Backbone Bridging”

Provider Backbone Bridge 802.1ad

Interfaces Provider Bridge Network (802.1ad) Network (802.1ah) Provider Bridge Network (802.1ad) 802.1aj

Provider Bridge Network (802.1ad) 802.1ag Runs End-to-end 802.1ak Runs in 802.1ad & 802.1ah

Ethernet Service Types

MEF Ethernet Virtual Connections (EVCs)

E-LINE

Router Mesh

E-TREE

Hub & Spoke

E-LAN

Multi-Site Pt-Pt, Like Duplex Ethernet Any-to-any Pt-MPt, Like EPON Ethernet, Root-to-Leaf and Leaf-to-Root MPt, Like VLAN, Any-to-any

E-LINE Dominates Today

> E-LINE is a natural leased line replacement for subscribers • Ethernet leased lines offer high bandwidth • Lines provide bandwidth on demand • Interfaces are compatible with off the shelf Ethernet switches/routers • Best for router mesh > E-LINE provides natural migration for carriers • Consistent with current operations model • Allows carrier equipment reductions • Bill models can follow well understood FR services • Current QoS models allow both traffic control and service monitoring of E LINE service offerings • Service OAM models for E-LINE are relatively straightforward > Each E-LINE service instance requires 1 S-VLAN

E-TREE Ideal For ISP Connect

> E-TREE Future Service With Great Promise • Useful as a multiplexed connection to an application service provider like an ISP • Service is unlike traditional Ethernet since leaf nodes can not talk with each other > E-TREE has deployment issues • No clear billing model • For instance if one leaf is disconnected is the circuit down?

• What is the distance of the tree?

• OAM management not fully understood • QoS model non-existant, SLAs can only provide Best Effort

E-TREE S-VLAN Mapping

E-TREE

Hub & Spoke Pt-MPt, Like EPON Ethernet, Root-to-Leaf and Leaf-to-Root

Hub Port Spoke Ports

> Each E-TREE service instance requires 2 S-VLANs > Both S-VLANs comprising an E-TREE S-VLANs are unidirectional > The S-VLANs of and E-TREE service instance are typically on the multiplexed on the same port

Some Carriers Will Use E-LINE in Hub and Spoke Arrangement

E-LINE

Hub & Spoke Pt-Pt Root-to-Leaf and Leaf-to-Root

Hub Port Spoke Ports

> Hub port would usually be multipexed to allow the multiple Pt-Pt attachments.

> Each E-LINE is a seperate managed S-VLAN > This arrangement allows use of E-LINE management, billing, and QoS > Many more S-VLANs are required 39

E-LAN Many Future Applications

> E-LAN is deployed for broad connectivity in select network • Interconnect of multiple corporate sites • Multi-player gaming • Ubiquitous any-to-any connectivity • E-LAN has many future applications > E-LAN has deployment issues • Deployments are very spotty • Unclear billing model • How is availability defined?

• No definitions for QoS or performance measurement • What is the distance of a E-LAN • Unclear management models • Unlike existing carrier service offerings > Each E-LAN service instance is a single S-VLAN

Prototypical Major Metro Area

> Business Subscriber Population 100K-2M • San Jose Yellow Pages ~100K businesses • The SF Bay Area lists ~1M businesses > Large Business Sites 500-5,000 > Residential Subscriber Population 1M-20M > Leased Line Density 10K-200K • Roughly 1/10 Yellow Page Listings > Application Service Provider Sites 100-2000 • Large APSPs sites may service residental

Typical SP Network Scale Metro Scale

Major MSA Networks

Access >10,ooo

Remotes

>4,ooo

Remotes

Business

CLE

>10,ooo

CLEs

>1,ooo

CLEs

Small Office Medium Office Large Office >500

COs

>50

COs

100-200

COs

>20

COs

10-60

COs

Typical Metropolitan Serving Area – MSA > MSA example shown > ASIA/PAC more CO/MSA > Europe less CO/MSA 42

Support 1,000,000 Service Instances

> > > > > Must be able to support E-LINE service for leased line replacement for entire MSA • This is the way Ethernet is entering the markets • The objective is 200K E-LINE instances Must support E-LINE for APSP to Subscribers • Not all service providers will allow E-TREE because of deployment problems • The objective of an additional 200K E-LINE is adequate for transition until E-TREE • Requirements for around 10K E-TREE instances • Requires 20K S-VLANs Must support E-LAN for APSP and B-B • Advanced peer applications • Number of service instances speculative, however could be large Totals • 200K E-LINE S-VLANs for leased line replacement • 200K E-LINE S-VLANs for APSP • • 20K E-TREE S-VLANs ? E-LAN Service Instances Designing Into A Corner Will Not Instill Confidence In Future • Set Objectives to at least 1,000,000 service instances E-LINE, E-TREE, E-LAN • E-LAN service will eventually become important for coupling small groups • Allow E-TREE and E-LAN service scaling to at least 100,000 for future growth

Proposed Project Objectives

> Interconnect Provider Bridge (802.1ad) Networks in a manner that allows scaling of the Carrier Bridged Network to support at least 2^20 S-VLANs > Support at least 2^16 multipoint S-VLANs > Interconnect at least 256 Provider Bridged Networks

Provider Backbone Bridge Technology Principles

A Provider Bridge Scaling Solution “Provider Backbone Bridging”

Provider Backbone Bridge 802.1ad

Interfaces Provider Bridge Network (802.1ad) Network (802.1ah) Provider Bridge Network (802.1ad) 802.1aj

Provider Bridge Network (802.1ad) 802.1ag Runs End-to-end 802.1ak Runs in 802.1ad & 802.1ah

Provider Backbone Bridge Network

PB BB PB PB BB PB BB

PB BB PB

• • •

: Provider Bridge (as defined by 802.1ad)

BB PB

: Provider Backbone Bridge Edge

: Provider Backbone Bridge

BB PB PB

Terminology

BBN Provides Multi-Point B-VLANs Between PBNs PBN PBN

BB PB B-VLAN X

S-VLAN 4

BB PB BBN BB PB

S-VLAN 3

BB PB

PBN

BB PB BB PB

PBN S-VLAN 2

B-VLAN

Y S-VLAN 1 •

BB PB

Provider Backbone Bridge Model

Provider Bridge Relays Backbone Bridge Relays

PB PBI MIF 8.5,6.7,9.5

Relay PB MCF (D 6.5) MAC (802.3) MIF 8.5,6.7,9.5

S-VLAN Map Shim Imaginary MAC MIF Relay MCF BB MIF MCF MAC (802.3) MIF Relay MCF BB MAC (802.3) MIF MCF MAC (802.3) MIF Relay MCF BB MIF MCF MAC (802.3) Imaginary MAC MIF 8.5,6.7,9.5

S-VLAN Map Shim Relay MIF 8.5,6.7,9.5

PB MCF (D 6.5) MAC (802.3) PB PBI

Backbone Bridge Interfaces Provider Bridge Interfaces

Backbone Core Relays Can be 802.1ad

Provider Bridge Network

PB MIF 8.5,6.7,9.5

MCF (D 6.5) MAC (802.3) Relay PB MIF 8.5,6.7,9.5

S-VLAN Map MIF Relay MCF BB MIF MCF Backbone Core Relay MIF MIF BB MCF MCF MIF Relay MCF BB MIF MCF PBI Imaginary MAC

Backbone Edge

MAC (802.3) MAC (802.3) MAC (802.3) MIF 8.5,6.7,9.5

S-VLAN Map Relay PB MIF 8.5,6.7,9.5

MCF (D 6.5) MAC (802.3) MAC (802.3) Imaginary MAC

Backbone Edge Provider Bridge Network

PBI PB 51

PB PB BB PB BB PB BB

> >

PB PB BB PB BB PB

Backbone Core can be single 802.1ad relay Backbone Edge is a dual 802.1ad relay and an encap/decap between the two relays.

Customer, PB, BB Spanning Trees

Customer Spanning Trees

QB QB QB QB QB PB PB-BB PB PB PB PB PB Spanning Trees BB PB-BB BB Spanning Trees BB PB-BB PB PB PB PB PB PB Spanning Trees QB QB QB QB QB

> > > Customer spanning trees may extend over Provider Network PB Network and BB Network spanning trees must be decoupled to scale the provider network Provider Backbone Bridge may conform to the requirements for an Interconnect Medium

Provider Bridge Island BPDUs Delivery Inside Provider Backbone Bridge BB PB BBN BB PB BB PB BPDU 1 BB PB

PBN

BB PB BB PB

PBN 2

BPDU 2

•

BB PB

: Provider Backbone Bridge Edge • • • • Each Provider Bridge Island may be connected to multiple Provider Backbone Bridge ports Provider Bridge Islands may not connect directly to each other Provider Backbone Bridge delivers Island BPDUs to all ports of that Island Island BPDUs are never delivered to other Islands by the BBN

BB Functions In Map Shim

802.1ad

Relay MIF MIF MCF BB MCF

802.1ad

Relay MIF 8.5,6.7,9.5

MIF 8.5,6.7,9.5

PB MCF (D 6.5) MCF (D 6.5) MAC (802.3) S-VLAN Map Shim MAC (802.3) Virtual MAC

Backbone Edge

> > > > Does encap/decap of 802.1ad frame Maps S-VID from 802.1ad into larger Extended Service VID (XS-VID) Learns and Correlates Backbone POP and Customer MAC addresses Filters L2 control packets sourced by core relays or by provider bridge relays (divides spanning trees)

Map Shim Encap

• • • BBN encapsulates PBN frames with BBN header BBN header consists of a) b) Extended Service VLAN identifier − Identifies the Provider Bridge S-VLAN within the BBN − Requires 2^20 bits to identify 1M services Site Connectivity identifier − Identifies a B-VLAN (or tunnel) that is used to transport the BBN service instance − Site connectivity (i.e., tunnel/domain) can be point-to-point or multi-point in nature c) Backbone POP Address MAC Address for POPs within Site Connectivity PBN Service VLAN IDs (S-VIDs) map to BBN Extended Service VLAN IDs (XS-VIDs) − − PBN S-VIDs are local to the PBN BBN XS-VIDs are local to the BBN 55

Backbone Frame Format

PB Frame Format

MAC DA MAC SA S-TAG Payload FCS

BBN Frame Format

BBN Frame Header MAC DA MAC SA Payload BBN FCS > Removing S-Tag is most efficient encode > Since FCS is also most efficient encode > Un B-Tagged frames could be used 56 > B-Tag format should be identical to 802.1ad

BBN Frame Header

B-MAC DA B-MAC SA B-TAG XS-TAG

MAP Shim on Ingress or Egress

MIF 802.1ad

Relay MIF BB MCF MCF MAC (802.3) S-VLAN Map Shim MAC (802.3) MIF 8.5,6.7,9.5

802.1ad

Relay MIF 8.5,6.7,9.5

PB MCF (D 6.5) MCF (D 6.5) MAC (802.3) S-VLAN Map Shim MAC (802.3)

Backbone Edge

> Both work > Best if located in one or the other 57

Backbone Access

S-VLANs Multiplex into B-VLANs

B-VLANs S-VLANs

BBI PBI Backbone Bridge (802.1ad) BB Relay MAP Shim PB Relay Provider Backbone Edge Bridge Provider Bridge (802.1ad)

> MAP Shim performs encap/decap of frames to/from Provider Bridge Networks

Extended Service VLAN IDs In Backbone

B-VLAN X BB PB

S-VID 32 S-VLAN 4 S-VID 41

BB PB

XS-VID 4

BBN BB PB

S-VLAN 3 S-VID 33 XS-VID 3

BB PB

S-VID 31

BB PB BB PB

S-VID 42

B-VLAN

Y S-VLAN 1 S-VLAN 2 •

BB PB

: Provider Backbone Bridge Edge • • • An XS-VID uniquely identifies a S-VLAN within the Backbone The MAP Shim translates between S-VID and XS-VID The XS-VID to(from) S-VID mapping is provisioned when a new service instance is created 59

Single XS-VID per S-VLAN

S-VID 2 BB PB BBN BB PB XS-VID S-VID 1 BB PB BB PB S-VID 3

> Regardless of the XS-VID address size the map tables only have 4096 entries since only one XS-VID exists per S-VLAN and only 4096 S VLANs exist per Provider Bridge.

> A different S-VID in each PBN maps to the XS-VID

Site Connectivity B-VLAN ID

B-VLAN X BB PB

S-VLAN 4

BB PB BBN BB PB

S-VLAN 3

BB PB

> >

BB PB BB PB

S-VLAN 2

B-VLAN

Y S-VLAN 1 B-VLANs are addressed like regular VLANs with a 12 bit B-VID B-VID and XS-VID need to be separate ID spaces to allow many S-VLANs to be carried in a single B-VLAN

Backbone POP MAC Address

BB PB BBN BB PB B-MAC 4 BB PB

Frame > > > > >

B-MAC 1 BB PB

Frame DA <- B-MAC 4 SA <- B-MAC 1 Frame B-MAC Addresses identify the Edge Provider Backbone Bridges (BB PB) B-MAC Addresses are learned by other Edge Backbone Edge Bridges The backbone edge MAC address determines which edge on the B-VLAN will receive the frame.

Frames may be flooded by sending with broadcast or multicasts DA B-MACs to the B-VLAN.

Map shims filter based on the XS-VID removing any misaddressed frames

Customer/Provider Addresses

Provider MAC Addresses

Relay MIF MIF

Customer MAC Addresses

Relay MIF 8.5,6.7,9.5

MIF 8.5,6.7,9.5

PB MCF (D 6.5) MCF (D 6.5) > PB Relay Learns Customer Address Per S-VLAN > BB Relay Learns Provider Addresses Per B-VLAN > MAP Shim Learns Correlated Customer and Provider MAC Addresses per S-VLAN MCF BB MCF S-VLAN Map Shim MAC (802.3) MAC (802.3) Virtual MAC

Backbone Edge Customer/Provider MAC Address Correlation

MAP Shim Correlation Table

Provisioned

S-VID

0x001 0x002 0xfff

XS-VID

0x010090 0x070707

B-VID

0x0c0 0x007 0x808080 0x0c0

Provider Addresses

B-MAC Addresses 0x999999999999 0x111111111111

Customer Addresses

C-MAC Addresses 0x888888888888 0x222222222222 C-MAC Address 0x777777777777 0xdddddddddddd > In the beginning the MAP Shim is provisioned with the correlation between the S-VID, XS-VID, and B-VID > During operation the MAP Shim learns both B-MAC addresses and C-MAC addresses > The MAP Shim keeps track of which C-MAC addresses are behind which B MAC > The correlation data is used to encapsulate frames from the PBNs

Basic MAP Shim Operation

> Frames received from PB Relay are encaped • S-VID is looked up in correlation table to get XS-VID and B-VID • C-DA is looked up in C-MAC table to get B-MAC for encapsulation • If C-DA is not present in C-MAC table then multicast to B-VLAN > Frames received from BB Relay are de-encaped • XS-VID is looked up in correlation table to get a new S-VID > B-MAC and C-MAC addresses are learned when frames are received from BB relay > B-MAC and C-MAC addresses are aged

Summary

> A Provider Backbone Bridge standard needs to define the functions of the MAP Shim > The 802.1ad control plane may be used on both sides of the MAP Shim > Connection Fault Management 802.1ag should be supported by the Provider Backbone Bridges

Backup Material

Terminology

> IEEE 802.1ad Terminology • C-TAG Customer VLAN TAG • C-VLAN Customer VLAN • C-VID • S-TAG • S-VLAN • S-VID Customer VLAN ID Service VLAN TAG Service VLAN Service VLAN ID > Additional Provider Backbone Bridge Terminology • XS-TAG Extended Service VLAN TAG Field (I-TAG) • XS-VID • C-MAC Extended Service VLAN ID (SID) Customer MAC Address • B-MAC • B-VLAN • B-TAG • B-VID Backbone MAC Address Backbone VLAN (tunnel) Backbone TAG Field Backbone VLAN ID (tunnel)

Service Instance Address Space Size Options

> Carriers need to separate the service address space to allow administration of networks • Allocation of address blocks to offices • Merging network elements > The address space usually needs to be 10-100 times larger than the number of services supported > Should have an address space around 2^24 > Use of 2^20 address space would match MPLS > Need to resolve this issue

Provider Backbone Bridges May Apply the 5 IM Rules.

1. Each 802.1ad island is responsible for preventing internal forwarding loops.

2. The 802.1ad islands connect to other only through Provider Backbone Bridge.

3. Each 802.1ad island ensures that no customer data frame passes through more than one Provider Backbone Bridge attachment into or out of the island.

4. Each 802.1ad island ensures that it attaches any given S-VLAN to no more than one Provider Backbone Bridge network.

5. A Provider Backbone Bridge network ensures that if an attached port can talk to any other attached port, it can talk to all of the ports attached to the Backone network.