Metro Ethernet and evolution of Virtual Private LAN Services (VPLS) K. A. K. Perera MEng CEng MIET Deputy General Manager Data Services & VoIP Sri Lanka

Metro Ethernet and evolution of Virtual Private LAN Services (VPLS)

K. A. K. Perera MEng CEng MIETDeputy General ManagerData Services & VoIP Sri Lanka Telecom

Requirements of Customers

Metro Ethernet Models

Metro Ethernet Services

Ethernet over IP/MPLS

Discussion

Agenda





Discussion

Agenda

High Speed Connectivity (10,20,50 Mbps….) Point to Point Data Connectivity

Network Connectivity

Internet Connectivity

Better Service Levels Network availability - 99.999% (Can go out of service

only 5.256 minutes per year)

Ring Access Networks

Highly available Data Nodes

Fast network resiliency


New and enhanced Services LAN interconnections

Virtual Private LAN Services (VPLS)

Enhanced QoS (Quality of Service)

Cost Effectiveness Multiple Services on a single port

Cheap Services – particularly at higher speeds


What is the solution ?

Metro Ethernet

Why Ethernet ?

- Most common Interface today

- Cost effective

- Supports very high Bandwidths (upto 1Gbps)

- Flexible upgrades within a wide range

(1Mbps to 1Gbps)

- Easy and simple to manage and maintain

What is Ethernet ?

Ethernet is a standard communications protocol embedded in software and hardware devices, intended for building a Local Area Network (LAN).

Ethernet transmits data at 10Mbps, Fast Ethernet supports up to 100Mbps and Gigabit Ethernet supports up to 1Gbps.

What is Metro Ethernet ?

Metro Ethernet is a standardized, carrier-class service defined by five attributes

Service providers worldwide are migrating their networks to deliver Metro Ethernet services





Discussion

Agenda


QinQ (Stacked VLAN)

- IEEE 802.1ad

MinM (Backbone Provider Bridge)

- IEEE802.1ah

Ethernet over IP-MPLS (Pseudowires)

- IETF RFC 4448

payloadDA SA FCS802.1q 802.1q

a1 Q

a1 Q Qa1 Q

Service Provider

Metro Ethernet

QinQ Principle

Enterprise CPE

Enterprise CPE

Carrier Access

Carrier Access

a1 b1

b1 Q b1

b1

Ethernet Access

b1a1 Q

Customer

MinM Principle

Site X

Site Y

Service Provider Metro Ethernet

network

Ethernet Switches

Enterprise Ethernet header

User data

SP Ethernet header

Ethernetpacket arrives from enterprise CPE node at SP ingress switch

EthernetUNI

(source)

SP Ingress switch adds SP Ethernet headerSrc and Dest MAC addresses are Ethernet UNI ports

EthernetUNI

(destination)

Ethernet packet switched across the Service Provider network using details in SP Ethernet header

SP Egress switch removes SP Ethernet headerAnd forwards original Ethernet packet to end customer CPE





Discussion

Agenda


- High Speed Data Links (VLL)

(LAN interconnections) - Virtual Private LAN Services (VPLS)- High Speed Internet- Access to IP-VPN main links

(VPN backhauling)

Typically required to connect;

- Headquaters Building (Main Link)

- Dissaster Recover Centers (DRC)

(LAN interconnections)

High Speed Data Links (VLL)

Metro Ethernet

LAN interconnection

Head QuartersDRC Site

Virtual Private LAN Services (VPLS)- Customer feels like remote offices are

connected to the same LAN

Metro EthernetBranch A

Branch C

Branch B Head Quarters

VPLS

Applications;

- Web browsing

- Hosting applications

- Video Straeming

- Multimedia

- Cyber Cafe

High Speed Internet Links

Metro Ethernet

Internet

VPN back-hauling

- Metro Ethernet is used as the Access Network

Existing IP/MPLS Backbone Metro Ethernet

IP-VPN

SiSi

VPN Back-haul

Edge Router

M-Agg

Branch A

Branch BBranch C

Head Quarters

IP-VPN

Multiple Services on single port- IP-VPN back-hauling- Layer 2 VPN services (VPLS)- High Speed Data Links

(LAN interconnections)- High Speed Internet Single Port

PE

CPEIP-VPN

High Speed Internet

VPLSHigh Speed Data

Metro Ethernet

Available Speeds;

- From 1 Mbps to 1000Mbps (1Gbps) Low Speeds (proposed);

- 1, 2, 3, 4, 5, 6, 8, 10Mbps High Speeds (proposed);

- 10, 15, 20, 25, 30, 35, 40, 50, 75, 100Mbps,1Gbps

Available Speeds





Discussion

Agenda

Why MPLS for Ethernet Services (EoMPLS)?

More Scalable (Free label Space) Sub 50msec resiliency (MPLS Fast

Reroute) Traffic Engineering (RSVP-TE) Hierarchical QoS (HQoS) Easy and simple to operate and

maintenance

Ethernet Services across MPLS

P2P Ethernet Service;Pseudowire (draft-martini) – VLL

High Speed Data Links – LAN interconnections High Speed Internet Access to IP-VPN main links (VPN backhauling)

MP2MP Ethernet Service;Virtual Private LAN Services – VPLS

Modes of Pseudowires PW can be configured as;

Raw Mode – Virtual connection (VLL) between two Ethernet ports

Tagged Mode – Virtual connection (VLL) between two VLAN (802.1Q) ports

payloadDA SA FCS802.1q

payloadDA SA FCS

Pseudowire – Draft Martini

PWs are constructed by building a pair of unidirectional MPLS (Label Switch Paths) LSPs between PEs

LSP labels can be;Statically assigned orAssign using LDP or RSVP

PW

LDP with directly connected PEs

CE CEPE 1 (LER 1) PE 1 (LER 2)

(Label 102)

(Label 201)

VC LSPs

102

MPLS Packet

102PW(VC) Label

Ethernet

Packet

Ethernet

Packet

LDP Session

This type of encapsulation is used to tunnel ATM, FR and other circuit emulation traffic too

payloadDA SA FCS802.1q payloadDA SA 802.1q

payloadDA SATunnelLabel

DA’ SA’ 802.1q FCS

FCS

VPLS - Introduction

VPLS (L2VPN); Configure on the MPLS Offers MP2MP

VPLS emulates a LAN, which provides; Full learning capabilities and Full switching capabilities

VPLS allows Customers to fully control their Routing (IP, IPX, IPv6)

VPLS Reference Model

VPLS A

VPLS B

VPLS B

VPLS A

VPLS A

VC LSPs

LAN Services

LSP Tunnels (Pseudowire)

PE 1 PE 2

PE 3

CE

CE

• PEs can participate in one or many VPLS domains• CEs visualize VPLS like an Ethernet Switch• Broadcast domains are maintained per VPLS basis by PEs

CE

CE

SLT Metro Ethernet (MPLS)

VPLS requirements

Separation between VPLS domains;Each customer domain emulates its own

LANVPLS PEs must maintain separate Virtual

Switching Instance (VSI) per VPLS MAC learning;

Capable of learning and forwarding based on MAC addresses

VPLS requirements (Cont.)

Switching;VPLS should be capable of switching

packets between different tunnels based on MAC addresses

Flooding;VPLS should be able to support the flooding

packets with unknown MAC addresses

Hierarchical VPLS (HVPLS)

MTU

Spoke VCs

Spoke VCs

Hub VCsHub VCs

MTUPE

PE

PE

PE

MTU

MTU

MTU

MTU

CE Routers

VLANs, Stacked VLANs or VC Labels

VLANs, Stacked VLANs or VC Labels

MTUPE

PEMTU

MTUMTU

MTU

MTU

PE

PE

MTU

MTU

Not scalable Hierarchy reduces full mesh network - scalable

Configurations of VPLS

VPLS APE 1 PE 2

PE 3

CE

1) Bridged VPLS – VPLS and Customer LANs are in the same broadcast domain (Routers not required)

CE

Metro Ethernet (MPLS)

CE

Configurations of VPLS

VPLS BPE 1 PE 2

PE 3

CE

2) Routed VPLS – VPLS and Customer LANs are in different broadcast domains

(Routers/L3 Switches are required)

CE

Metro Ethernet (MPLS)

CE

Quality of Service (QoS)

Reserve 8 Mb/s

Reserve 2 Mb/s

Reserve 2 Mb/s

Reserve 4 Mb/s

16 Mb/s

DSCP=5=voice

DSCP=4=video

DSCP=1=Data

DSCP=0=Internet

Installed SLA Voice 2 Mb/s Video 2 Mb/s Data 4 Mb/s Internet 8 Mb/s TOTAL=16 Mb/s required

Actual usage Voice 1 Mb/s Video 1 Mb/s Data 4 Mb/s Internet 8 Mb/s TOTAL = only 14 Mb/s

used If higher priority traffic is not consuming all the reserved

bandwidth, the lower priority forwarding classes cannot use the remaining bandwidth – Solution HQoS

Normal QoS Vs HQoSNormal QoS Hierarchical QoS

Strict / WeightedRate Limiting

Schedule


Schedule


Schedule


Schedule


Schedule

Queue

Queue

Queue

Queue

Queue

Queue


Schedule

Queue

Queue

Queue

Queue

Queue

Queue

Unique 3-level parent/child scheduling Maintains relative priorities Enables lower priority bursting when higher priority is below

CIR

DSCP=5=voice

DSCP=4=video

DSCP=1=Data

DSCP=0=Internet

High Speed Resiliency

- The switchover from the working link to the protection link will happen within sub 50ms to ensure that no impact on real time applications- MPLS (Multi Protocol Label Switching) with MPLS Fast Reroute enables this feature

R1

R2 R3 R4

R5

R6 R7 R8

R9

End-to-End

Repair

Point of Local Repair

(PLR)

Detour LSP

Primary Path

Secondary Path

Existing IP/MPLS Backbone

Reference Network – SLT

Slave Island

Liberty plaza

Colombo

Havelock town

Maradana

SiSi

SiSi

SiSi

SiSi

SiSi

M-Agg

GE

N-PE

SiSi

10GE

SiSi

SiSi

SiSi

SiSi

SiSi

L2 MPLS Aggregation

Ring

5 Rings

1 Ring

1 Ring

3 Rings

3 Rings

Ethernet service revenues

$0$2,000$4,000$6,000$8,000

$10,000$12,000$14,000$16,000$18,000$20,000

2003 2004 2005 2006 2007

EthernetServices

Concluding Remarks

“Metro Ethernet” delivers cost effective, high speed, scalable, reliable and multi-service Ethernet services to the customers through the sate-of-the-art MPLS technology





Discussion

Agenda

Thank you

Documents

Metro Ethernet and evolution of Virtual Private LAN Services (VPLS) K. A. K. Perera MEng CEng MIET Deputy General Manager Data Services & VoIP Sri Lanka