Carrier Ethernet Technologies

Mateusz FirutaCESD ConsultantMarch 2011

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Carrier Ethernet Defined

A set of certified network elements that connect to transport Carrier Ethernet services for all users, locally & worldwide

Carrier Ethernet services are carried over physical Ethernet networks and other legacy transport technologies

Carrier Ethernet for Service Providers:

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Carrier Ethernet – Standardized Services E-Line and E-LAN Services

E-Line Service used to create

Ethernet Private Lines

Virtual Private Lines

Ethernet Internet Access

E-LAN Service used to create

Multipoint L2 VPNs

Transparent LAN Service

Foundation for IPTV and Multicast networks etc.

E-Line Service type

Point-to-Point EVC

Carrier Ethernet Network

UNI: User Network InterfaceCE: Customer EquipmentEVC: Ethernet Virtual Connection

CE

UNI UNI

CE

MEF certified Carrier Ethernet products

E-LAN Service type

Multipoint-to-Multipoint EVC

Carrier Ethernet Network

CE

UNI

CEUNI

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Used for Applications requiring Point-to-Multipoint topologyVideo on demand, internet access, triple play backhaul, mobile cell site backhaul, franchising applications

Provides traffic separation between ‘Leaf’ UNIsTraffic from any “leaf” UNI can be sent/received to/from “Root” UNI(s) but never being forwarded to other “Leaf” UNIs

Root

CEUNI

UNI

UNI

CE

CE

Leaf

Leaf

UNI

CE

Leaf

Rooted Multipoint EVC

Carrier Ethernet – Standardized Services E-Tree Services

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802.1Q Frame

Double-tagging enables a separation between each customer’s traffic within the service provider network

802.1ad (Q-in-Q) Frame

Service Provider VLAN

S-VLAN TAG

Customer VLAN

C-VLAN TAG

VLAN Frame

FCSDestinationAddress

SourceAddress

UserProtocol

TypeUser Data FCS

6 bytes 6 bytes 2 bytes 46 to 1982 bytes 4 bytes VLAN

ProtocolType

0x8100

4 bytes

VLANID

FCSDestinationAddress

SourceAddress

UserProtocol

TypeUser Data FCS

6 bytes 6 bytes 2 bytes 46 to 1982 bytes 4 bytes S-VLANProtocol

Type0x88A8

4 bytes

C-VLANID

C-VLANProtocol

Type0x8100

C-VLANTAG

4 bytes

Carrier Ethernet – ScalabilityIEEE 802.1ad Provider Bridges (Q-in-Q)

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• Scalability• Still limited to 4094 SP VLANs (services)• If each customer requires 3-5 services, only ~800 subscribers

• Transparency• Service Provider provides cust-VID transparency through P-VID

• Security– No clear demarcation between SP and customer (no MAC addressing separation

between SP and customer)– SP network still exposed to attacks (spoofing, DOS, STP/RSTP exploits)

• Reliability– No separation between customer and SP reliability mechanisms (STP) so the

convergence impacts the entire network

Carrier Ethernet – ScalabilityIEEE 802.1ad Provider Bridges (Q-in-Q) cont.

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DASA

Payload

DASA

Payload

VID

DASA

Payload

S-VID

C-VID

DASA

Payload

802.1basic

802.1Qtagged VLAN

VID = VLAN IDC-VID = Customer VIDS-VID = Service VIDI-SID = Service IDB-VID = Backbone VIDB-DA = Backbone DAB-SA = Backbone SA

I-SID

Ethertype Ethertype

Ethertype

Ethertype

Ethertype

Ethertype

S-VID

C-VID

Ethertype

Ethertype

Ethertype

B-DAB-SA

B-VIDEthertype

Ethertype802.1ad

QinQProvider Bridge

802.1ahMACinMAC

PBB

Pre-existing (unchanged)

New (backbone)

Carrier Ethernet – ScalabilityIEEE 802.1ah Provider Backbone Bridges (Mac-in-Mac)

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IEEE 802.1ah is the Provider Backbone Bridge standard

Also known as Mac In Mac (MiM) encapsulation

PBB solves several of today’s Ethernet challenges

Service Scalability – up to 16 millions VPNs

Customer Segregation – Overlapping VLANs supported

MAC Explosion – Customer MAC addresses only learned at edge

Security – Customer BPDUs are transparently switched

DASA

Payload

S-VC-VID

B-DAB-SAB-VID

802.1ahProvider BackboneBridges

I-SID

Carrier Ethernet – ScalabilityIEEE 802.1ah Provider Backbone Bridges (Mac-in-Mac) cont.

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PEPE

A B

MPLS Tunnel from A to B

Ethernet PWE between A & B

Ethernet Attachment CircuitVLAN 100 on port 1 slot 2Ethernet Attachment Circuit

VLAN 100 on port 1 slot 2

DATADA|SA|VID

DATADA|SA|VID

CW

VC

TL

Transport

DATADA|SA|VID

Classify on VID 100 andMap to PWE

Carrier Ethernet – ScalabilityMPLS/VPWS – Ethernet Pseudowires

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VPLS

Full Mesh of PWEs required edge to edge

Transport VPLS Forwards on B-DATransport VPLS Learns on B-SA

Carrier Ethernet – ScalabilityMPLS/VPLS – Ethernet LAN Services

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Originally introduced to alleviate control plane scaling issueMPLS Tunnel Hierarchy

Reduce PWE E-LDP Peering Side benefit of mitigating some of the multicast inefficiencies

N-PEsU-PEs U-PEs

Carrier Ethernet – ScalabilityVPLS Story for Scaling: H-VPLS

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Mesh topology is good for resilience but bad for bridging.

Bridges use STP to detect “loops” and break them

Whenever a loop (i.e. redundant port) is found, a port is blocked (taken out of service) to break the loop

STP continually monitors the network. If a link goes down, the appropriate port is brought back into service to heal the network and restore connectivity

IEEE 802.1w – Rapid Spanning Tree (RSTP): Improved original STP transition time from seconds to milliseconds when moving ports from blocked to forwarding.

IEEE 802.1s – Multiple Spanning Tree: Allows individual STPs to run on a per VLAN basis to assure that the optimal traffic paths are always available.

R R

This link brought back into service

Carrier Ethernet – ReliabilitySpanning Tree Protocol (STP), Rapid, Multiple

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Use of standard 802 MAC and OAM frames around the ring. Uses standard 802.1Q (and amended Q bridges), but with xSTP disabled.Ring nodes supports standard FDB MAC learning, forwarding, flush behaviour and port blocking/unblocking mechanisms.Prevents loops within the ring by blocking one of the links (either a pre-determined link or a failed link).

Monitoring of the ETH layer for discovery and identification of Signal Failure (SF) conditions.Protection and recovery switching within 50 ms for typical rings.Total communication for the protection mechanism should consume a very small percentage of total available bandwidth.

Carrier Ethernet – ReliabilityG.8032 Ethernet Ring Protection Switching (E-SPRing)

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A. Physical topology has all nodes connected in a ring

B. ERP guarantees lack of loop by blocking the RPL (link between 6 & 1 in figure)

C. Logical topology has all nodes connected without a loop.

D. Each link is monitored by its two adjacent nodes using ETH CC OAM messages

E. Signal Failure as defined in Y.1731, is trigger to ring protection

Loss of Continuity

Server layer failure (e.g. Phy Link Down)

RPL Owner

RPL

ETH-CC

ETH-CC

ETH-CC

ETH-CC

ETH-CC

ETH-CC

ETH-CC

ETH-CC

ETH

-CC

ETH

-CC

ETH

-CC

ETH

-CC

Physical topology

Logical topology

12 6

43 5

RPL

12 6

43 5

Carrier Ethernet – ReliabilityG.8032 Ethernet Ring Protection Switching (E-SPRing) cont.

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A. Link/node failure is detected by the nodes adjacent to the failure.

B. The nodes adjacent to the failure, block the failed link and report this failure to the ring using R-APS (SF) message

C. R-APS (SF) message triggers RPL Owner unblocks the RPL All nodes perform FDB

flushing

D. Ring is in protection state

E. All nodes remain connected in the logical topology.

Physical topology

Logical topology

12 6

43 5

RPL12 6

43 5

RPL

12 6

43 5

12 6

43 5

RPL Owner

RPL

R-APS(SF) R-APS(SF)

R-APS(SF)

R-A

PS(SF)

Carrier Ethernet – ReliabilityG.8032 Ethernet Ring Protection Switching (E-SPRing) cont.

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P2P traffic engineered trunks based on existing Ethernet forwarding principlesReuses existing Ethernet forwarding plane

Simple L2 networking technologyTunnels can be engineered for diversity, resiliency or load spreading50 ms recovery with fast IEEE 802.1ag CFM OAM

Ethernet Metro

Traffic engineered PBB-TE trunks

E-LINE

PBBE-LINE

PBB

Carrier Ethernet – ReliabilityIEEE 802.1Qay PBB-TE

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Ethernet Challenges:

Customer Segregation

Traffic engineering

Spanning Tree challenges: Stranded bandwidth Poor convergence

MAC explosions

Security

Full segregation in P2P model

End to End TE With QoS & 50 ms recovery

Disable STP No blocked links Fast 802.1ag convergence

MAC Explosions Eliminated

Backbone MAC is Completely Different Than Customer MAC

Carrier Ethernet – ReliabilityIEEE 802.1Qay PBB-TE cont.

18Trend

Wide interest from vendors and operators

PHPLSP MergeLDPIP Forwarding

MPLS/PWE ArchMPLS ForwardingGMPLS/PWE3 Control plane

ProvisioningProtection

QoSOAM

MPLS MPLS-TP

(8) RFCs

(2) RFCs

awaiting publicatio

n

(28) IETF

drafts

Carrier Ethernet – ReliabilityMPLS-TP

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Primary ApplicationsScaling metro/core networks with lower-cost transit LSRs (IP-free dataplane)MBH access/aggregation technology (replaces connection-oriented e.g., PBB-TE)

MPLS-TP benefitsLower-cost, more scalable transit LSRsExtensive OAM, FM, PM

IETF defining IP-based OAM for VPLS/VPWS, as well as for LSPs, including connectivity check (BFD/vccv, for supporting 50ms protection switching), frame loss, delay, jitter, AIS, RDI, Lock, Loopback, etc. (although most of them are not defined yet but the requirements have been defined).

Carrier Ethernet – ReliabilityMPLS-TP

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Carrier Ethernet – Service ManagementPhysical Link – IEEE 802.3ah Link Based

Dying Gasp Reported (Fault Signaling) Link Loopback

Service Affecting Active or Passive modes supported on per Port Basis

Errored Frame Seconds and Thresholds OAM Discovery

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Proactive or on-demand service connectivity mgmt

MEP 10

MEP 12

MEP 11

MIP

MIPMIP

Per VLAN/Tunnel MAC PingPer VLAN/Tunnel MAC TraceroutePer VLAN/Tunnel Continuity Check

Constantly Checks Service StateCreates Trap if 3 CCMs are lost3.3msec to 10min intervals

Non-Service Affecting All CESD Switches Management End-Points Management Intermediate-Points 7 Maintenance Domains Supported Auto Discovery of MEPS/MIPS

Carrier Ethernet – Service ManagementConnectivity Fault Management – IEEE 802.1ag

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Non-Service Affecting Utilizes IEEE 802.1ag format frames for test packets Unicast messages to a specific MEP Delay, Jitter, and Frame Loss measurements Allows continual background SLA monitoring of loss, delay, and jitter to selected

MEPs MIPs do not participate in delay/jitter/frame loss measurements

MEP 10

MEP 12

MEP 11

MIP

MIPMIP

802.1ag CCMs

Service Performance Monitoring / SLA Monitoring

Carrier Ethernet – Service ManagementPerformance Monitoring– ITU-T Y.1731

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IP network

L3 based measurement of delay/jitter values between two end pointsOperator configures a “test interface” on the endpoints and associates that

endpoint with a particular serviceTraverses L3 network since it is an L3 protocolTest will run for limited duration as specified by the operator

L3 service mgmt, traverses mixed CE/non-CE networks

ServerControl-client

Session-Sender

Session-Reflector or Responder

Carrier Ethernet – Service ManagementService Management – TWAMP (RFC 5357)

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CN 3916 will embed Packet Generator in the system, using dedicated CPU.External tester no longer required, along with truck-rollAllows testing without Service down-time

Tests are under control of ESMAcceptance and In-Service reports can be generated by ESM

2544 Throughput testing complements TWAMP & Y.1731 capabilities

2544 SessionSender

2544 SessionReflector

Line Rate

0

5000

10000

15000

20000

25000

30000

FPS

64 128 256 512 1024 1280 1518Frame Size

Acceptance report

Carrier Ethernet – Service ManagementThroughput Testing– RFC 2544 Perhaps Y.156Sam ???

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Specific service identification with rich classification

Ports, MAC Addr, VLANs, EtherType, Priority, MPLS label, L3/L4 fields

Mapping to specific customer needs (Departments, applications, etc.)

Segmented bandwidth via a hierarchy of “virtual ports”

Traffic profiles and traffic management at all levels in the hierarchy

Tightly controlled, and measurable bandwidth for secure, predictable service delivery

80/200

30/100

50/100

MAC SA A

Logical Port(e.g. all the client ports of a Business)

Sub-Port(e.g. Dept VLAN range)

Flow Interface (e.g. Combo of TCP/UDP port, IP DSCP, MAC, etc.)

TCP port 80

Voice VLAN

MAC DA B

L2VPN

20/55

10/40

20/0

0/100

25/100

IP SA 192.168.1.23DENY

CIR/EIR

Carrier Ethernet – Quality of ServiceGranular Bandwidth Control

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Packet Network Time Synchronization

Sync-E (G.8261) provides frequency sync only sufficient for 2G/3G non-TDD radio technology

IEEE 1588v2 (G.8262) provides frequency and phase sync

Ordinary Clock (OC) at cell sites

Transparent Clock (TC) deployed strategically

Boundary Clock (BC) for regen & scalability

Sync-E requires all devices along the path from GM to radio be capable

1588v2 can traverse non-1588v2 aware L2/L3 switches

Ciena’s position

We will offer both Sync-E and 1588v2 OC & TC capabilities initially, with BC for future support

To meet LTE radio timing requirements Sync-E for frequency, 1588v2 for phase alignment

Access

Ring

Access

Ring

TransportRing

AccessRing

Transport

Ring

TC

TC

TC

BC

TC

BCTC

OC

OC

OC

OC

Evolved Packet Core

1588v2SyncE