Download ppt - V1.1 VPLS Principle. Objectives Understand the basics of mpls layer 2 VPN Understand VPLS principle

V1.1

VPLS Principle

Objectives

Understand the basics of mpls layer 2 VPN Understand VPLS principle

Contents

Basic Conception Of MPLS Layer 2 VPN VPLS Overview VPLS PE Functions VPLS Working Process

BGP MPLS/VPN feature

Establish tunnel on public network by LDP (Label distribution protocol)

Implement the following by using MBGP detection and transmission of VPN route Distribute inner layer label to implement address multiplexing

Implement route policy by using the extend attribute RT of BGP

Advantage of layer 3 MPLS VPN

Customer Outsource WAN infrastructure Transfer the route complexity to provider Suitable for middle or small sized company which do no

t want to gain core route capability in the company

Provider Do not need to maintain the route information among all

the core network routers Value added service（ chance to gain profit）

Disadvantages of layer 3 MPLS VPN

Control based on policy adds burden to provider Extensibility and management maybe problem to super

network Some customer hope to control their route hierarchy

Layer 2 MPLS VPN

Suitable for the access of big company

Features： Regard the access network as a huge switch Establish tunnel by using MPLS label Do layer 2 switch in the whole network

MPLS LSPATM/FRATM/FR

Advantage of layer 2 MPLS VPN

Customer Easy to implement on the current layer 2 structure Can maintain control of the route Support any layer 3 routing protocol

Provider No extensibility problem due to storing too many

customer VPN routes Comparably simple than layer 3 MPLS VPN that use a

lot of policy control

L2 MPLS VPN classification

VPWS： Virtual Private Wire Service

point to point connection

VPLS： Virtual Private LAN Service

point to multipoint connection

Contents


Ethernet develop problem

Widely used LAN technology Develop goal is to provide multipoint to multipoint Ethernet

service without the limitation of geography space Construct large scale Ethernet by switches

Instability of STP Broadcast storm Limited numbers of VLAN

Function of VPLS

By using Ethernet and MPLS to satisfy the need of Carrier and customer ,enabling the communication between customer’s networks in different place

VPWS only provide point to point connection, but VPLS provide point to multipoint connection

Carrier’s backbone network

VPLS working principle Establish LSP between

PEs Green user and red user

are in independent VPN Establish point to point

layer 2 VC LSP in LSP tunnel

CE can be switch or router

Any upper layer protocol MPLS backbone network

is like a LAN switch with high reliability and flexibility

VPLS standards

VPLS standard is not decided yet, the widely used are:

Martini draft Rather mature， and widely supported by manufactures Support multiple protocols Suitable to be used within AS Need to be configured manually

Kompella draft Use the same encapsulation as MARTINI Can be configured automatically Can be used between AS Only support IP protocol

VFI—Distinguish VPN user

VFI（ Virtual forwarding Instance） create a VPLS instance on PE， different VPLS instan

ces that have the same vc-id on different PE belong to one VPLS and can communicate with each other


PE1 CE3

CE2

PE2

Vfi vpls_aVcid=100Peer=PE2Int fei_1/1

Vfi vpls_aVcid=100Peer=PE1Int fei_1/1 fei_1/2

Fei_1/1Fei_1/1

Fei_1/2 CE1

VPLS PE router structure

PE include PW management and VPLS instance PW management is responsible for establishing and

maintaining the PW with other instances on different PE VFI implement MAC learning and MAC switching.

VPLS PE

VPLS PE

VPLS PE

PW management

VPLS instance

Contents


VPLS working process——establishing PW (Pseudo Wire)

establishing of PW is to exchange inner label or VC label which identifies VPLS between PE

Martini draft make some extensions to LDP, add VC FEC type（ 128 type and 129 type）


VPN1

VPN2VPN2

VPN1LSP

Assign virtual link label by LDP

Service Provider MPLS Backbone

Learn MAC address by broadcast

PE1

VPLS-B

VPLS

PE2

PE3

MAC XXX

MAC ZZZ

-A MAC YYY

Port 1

Port 1

Port 1

VPLSMAC

AddressLocation Port

100 XXX Local Port 1

PE1

VPLS-B


VPLS

PE2

PE3

MAC ZZZ

-A MAC YYY

Port 1

Port 1

Port 1

MACXXX

Learn MAC address by broadcast

VPLSMAC



VPLSMAC


100 XXX Remote Port 1

VPLSMAC



PE1

VPLS-B


VPLS

PE2

PE3

MAC XXX

MAC ZZZ

-A MAC YYY

Port 1

Port 1

Port 1

Learn MAC address by Unicast

VPLSMAC



VPLSMAC



100 zzz Local Port

VPLSMAC



PE1

VPLS-B


VPLS

PE2

PE3

MAC XXX

MAC ZZZ

-A MAC YYY

Port 1

Port 1

Port 1


VPLSMAC



100 ZZZ Remote Port1/LSP

VPLSMAC



100 ZZZ Local Port

VPLSMAC



PE1

VPLS-B


VPLS

PE2

PE3

MAC XXX

MAC ZZZ

-A MAC YYY

Port 1

Port 1

Port 1


VPLSMAC




VPLSMAC



100 ZZZ Local Port

VPLSMAC



100 YYY Local Port1

PE1

VPLS-B


VPLS

PE2

PE3

MAC XXX

MAC ZZZ

-A MAC YYY

Port 1

Port 1

Port 1


VPLSMAC




100 YYY Remote Port1/LSP

VPLSMAC



100 ZZZ Local Port

VPLSMAC



100 YYY Local Port1

VPLS loop problem——Horizon split

Virtual forwarding instance on PE is like a layer 2 switch, but it doesn’t need to run STP like traditional L2 switch because MPLS L2 VPN use internal horizon split mechanism to avoid loop.

Contents


VPLS working process—create inner label

Set VFI on PE， same VPLS has same vc-id in VFI Set interface on PE as layer 2 transparant transfer port Establish session to assign virtual link label by using extend LD

P

CE1

PE1 P PE2

CE2

Fei_1/2Fei_1/1 Fei_3/2

Fei_3/1

Fei_2/1 Fei_2/2

Vfi vpn_aVcid=100,peer=PE2Int fei_1/1

PE1:vcid=100 label:16

PE2:vcid=100 label:22

LDP LDP

Vfi vpn_aVcid=100,peer=PE1Int fei_3/2

VPLS working process—create outside label

PE and equipment run routing protocol and establish LSP by using LDP

CE1

PE1P

PE2

CE2


Fei_3/1

Fei_2/1 Fei_2/2

PE1: Lable 3 PE2: Lable 3

PE2: Lable 28 PE1: Lable 72

VPLS working process—form of label table

L2 label table and global label table formed on PE， global label table formed on P

CE1

PE1P

PE2

CE2


Fei_3/1

Fei_2/1 Fei_2/2

In-int In-label Dest out-label out-intFei_2/1 28 PE2 pop fei_2/2Fei_2/2 72 PE1 pop fei_2/1

Dest out-label out-intPE2 28 fei_1/2

In-int vc-id Dest out-labelFei_1/1 100 PE2 22

In-int vc-id Dest out-label Fei_3/2 100 PE1 16


VPLS working process—data forwarding

CE1 wants to communicate with CE2， sending ARP PE1 receives this packet， learn source MAC aaa and record

it in VFI

CE1

MAC:aaa

PE1P

PE2

CE2

MAC:bbb


Fei_3/1

Fei_2/1 Fei_2/2

MAC peer-address outIntLab outExtLab outIntaaa local null null fei_1/1

data

S:aaa,D:ffff


PE send to all the VCs according to destination MAC of packet

Search L2 label table and global label table to encapsulate packet

CE1

MAC:aaa

PE1 PPE2

CE2

MAC:bbb


Fei_3/1

Fei_2/1 Fei_2/2



dataS:aaa D:ffff

2228

data

S:aaa,D:ffff


P search label table to forward data and do Penultimate Hop Popping

CE1

MAC:aaa

PE1 PPE2

CE2

MAC:bbb


Fei_3/1

Fei_2/1 Fei_2/2

dataS:aaa D:ffff

2228

In-int In-label Dest out-label out-intFei_2/1 28 PE2 pop fei_2/2Fei_2/2 72 PE1 pop fei_2/1

dataS:aaa D:ffff

22

data

S:aaa,D:ffff


PE2 learn source MAC and record it in VFI PE2 send packet to CE2

CE1

MAC:aaa

PE1 PPE2

CE2

MAC:bbb


Fei_3/1

Fei_2/1 Fei_2/2

data

S:aaa,D:ffff

dataS:aaa D:ffff

2228

dataS:aaa D:ffff

22

MAC peer-address outIntLab outExtLab outIntaaa PE1 16 72 fei_3/1

In-int vc-id Dest out-label Fei_3/2 100 PE1 16


dataS:aaa,D:ffff


CE2 send back ARP response to CE1 PE2 learn source MAC and record it in VFI

CE1

MAC:aaa

PE1 PPE2

CE2

MAC:bbb


Fei_3/1

Fei_2/1 Fei_2/2

MAC peer-address outIntLab outExtLab outIntaaa PE1 16 72 fei_3/1bbb local null null fei_3/2

dataS:bbb,D:aaa


PE2 search and forward packet according to destination MAC

CE1

MAC:aaa

PE1 PPE2

CE2

MAC:bbb


Fei_3/1

Fei_2/1 Fei_2/2

MAC peer-address outIntLab outExtLab outIntaaa PE1 16 72 fei_3/1bbb local null null fei_3/2

dataS:bbb,D:aaa

dataS:bbb D:aaa

1672


PE1 learn source MAC in packet and record it in VFI PE1 search and forward packet according to destination MAC

CE1

MAC:aaa

PE1 PPE2

CE2

MAC:bbb


Fei_3/1

Fei_2/1 Fei_2/2

dataS:bbb,D:aaa

dataS:bbb D:aaa

1672

dataS:bbb D:aaa

16

MAC peer-address outIntLab outExtLab outIntaaa local null null fei_1/1bbb PE2 22 28 fei_1/2Dest out-label out-int

PE2 28 fei_1/2


data

S:bbb,D:aaa

Review

MPLS L2 VPN function VPLS function VFI function MAC address learning process VPLS working process

Question

How does VPLS solve the problem of loop？