(1.3) MPLS and MPLS TE Principle and Deployment in VNPT

8/12/2019 (1.3) MPLS and MPLS TE Principle and Deployment in VNPT

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Copyright 2011 Huawei Technologies Co., Ltd. All rights reserved. Page2

Foreword

Multiprotocol Label Switching is widely use in the network

nowadays to enhance the reliability of the network. One of

the popular application of the MPLS is MPLS TE.


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Objectives

Upon completion of this course, you will be able to:

Basic concept of MPLS

Working mechanism of MPLS

MPLS application MPLS TE

Working mechanism of MPLS TE

Application of MPLS TE in VNPT network


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Contents

1. MPLS

2. MPLS TE

3. Role of MPLS TE in VPNT Network


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Contents

1. MPLS

1.1 Introduction

1.2 Concept

1.3 Packet format

1.4 Working Mechanism


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Contents

1. MPLS

1.1 Introduction

1.2 Concept

1.3 Packet format



7/79Copyright 2011 Huawei Technologies Co., Ltd. All rights reserved. Page7

Traditional IP Forwarding

RTA RTB RTC RTD

10.1.0.0/24 10.2.0.0/24

10.1.1.0/30 10.1.1.4/30

s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

Network Nexthop

10.1.0.0/24 10.1.0.2

10.1.0.1/32 10.1.0.1

10.1.1.0/30 10.1.1.1

10.1.1.2/32 10.1.1.2

10.1.1.4/30 10.1.1.2

10.1.1.8/30 10.1.1.2

10.2.0.0/24 10.1.1.2

Network Nexthop

10.1.0.0/24 10.1.1.1

10.1.1.0/30 10.1.1.2

10.1.1.1/32 10.1.1.1

10.1.1.4/30 10.1.1.5

10.1.1.6/32 10.1.1.6

10.1.1.8/30 10.1.1.6

10.2.0.0/24 10.1.1.6

Network Nexthop

10.1.0.0/24 10.1.1.5

10.1.1.0/30 10.1.1.5

10.1.1.4/30 10.1.1.6

10.1.1.5/32 10.1.1.5

10.1.1.8/30 10.1.1.9

10.1.1.10/32 10.1.1.10

10.2.0.0/24 10.1.1.10

Network Nexthop

10.1.0.0/24 10.1.1.9

10.1.1.0/30 10.1.1.9

10.1.1.4/30 10.1.1.9

10.1.1.8/30 10.1.1.10

10.1.1.9/32 10.1.1.9

10.2.0.0/24 10.2.0.2

10.2.0.1/32 10.2.0.1

1 0

.1

. 0

. 0 / 3 0

.2

.1

1 0 .2 . 0 . 0

/ 3 0

.2

.1

D a t a

1 0 .2 .

0 .1


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The Weakness of Traditional IPForwarding at Traffic Engineering

RTA RTB RTD RTE

RTC

Network A

RTF

RTG RTH

GE GE

FE

FE

FE

100% Traffic

100% Traffic Network C

Network B


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Copyright 2011 Huawei Technologies Co., Ltd. All rights reserved. Page9Page9

MPLS Label Forwarding

RTA RTB RTC RTD

10.1.0.0/24

10.1.1.0/30 10.1.1.4/30s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

D a t a

I P

H e a d er MPLS Domain

1024 DataIP

Header

MPLS Header Data IP Header

1029 DataIPHeader 1039 DataIP

Header

D a t a

I P

H e a d er

10.2.0.0/24


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Contents

1. MPLS

1.1 Introduction

1.2 Concept

1.3 Packet Format



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1039 DataIPHeader1029 DataIP

Header1024 DataIP

Header

MPLS Network Model

RTA RTB RTCRTD

IP Network

MPLS Domain

LER

IP Network

LER

RTE

RTF RTG

LSR

LSP

D

a t a

I P

H e a d er

D

a t a

I P

H e a d er

LER Label Edge Router

LSR Label Switch Router

LSP Label Switch Path


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Contents

1. MPLS

1.1 Introduction

1.2 Concept

1.3 Packet format



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Frame mode MPLS

FrameHeader IP Header Payload

FrameHeader

MPLSHeader IP Header Payload

Layer 2 frame format

Frame mode MPLSencapsulation


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MPLS Header

The total length of MPLS header is 4bytes (32bits)The length of Label field is 20bits

The length of EXP Experimental Use field is

3bitsThe length of S Bottom of Stack field is1bit

The length of TTL field is 8bits

LABEL EXP S TTL

0 19 22 23 3120 24


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MPLS Label NestingFrameHeader Label 1 IP Header PayloadLabel 2 Label 3

S=0 S=0 S=1

PID=MPLS-IP

PID indicates the types of packet follows Frame HeaderEthernet 0x8100 IPv4 0x8847 Unicast MPLS packet 0x8848 Multicast MPLS packet

PPP 0x8021 IPv4 0x8281 Unicast MPLS packet 0x8283 Multicast MPLS packet

S indicates whether it is the last label

Applications of label nesting

MPLS VPN

MPLS TE


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Contents

1. MPLS

1.1 Introduction

1.2 Concept

1.3 Packet format



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Copyright 2011 Huawei Technologies Co., Ltd. All rights reserved. Page17Page17

MPLS Label Operation

RTA RTB RTC RTD

10.1.0.0/24

10.1.1.0/30 10.1.1.4/30

s0 s0s3

s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

D a t a

I P

H e a d er MPLS Domain

DataIPHeader

MPLS Header Data IP Header

DataIPHeader DataIP

Header

D a t a

I P

H e a d er

10.2.0.0/24

1024

PUSH

10241029

SWAP

10291039

SWAP

POP


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MPLS Forwarding Ingress LER

RTA RTB RTC RTD

10.1.0.0/24 10.2.0.0/24

10.1.1.0/30 10.1.1.4/30s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

D a t a

1 0 .2 . 0 .1 MPLS Domain

1 0

.1

. 0

. 0 / 3 0

.2

.1

1 0

.2

. 0

. 0 / 3 0

.2

.1


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MPLS Forwarding Ingress LER

FEC Forwardin g Equ ivalence Classes

NHLFE Next Hop Label Forwarding Entrydisplay mpls lsp include 10.2.0.0 24 verbose---------------------------------------------------

LSP Information: LDP LSP

---------------------------------------------------No : 1VrfIndex :Fec : 10.2.0.0/24

Nexthop : 10.1.1.2 In-Label : NULLOut-Label : 1030In-Interface : ----------Out-Interface : Serial0

LspIndex : 10249Token : 0x22005LsrType : IngressOutgoing token : 0x0Label Operation : PUSH Mpls-Mtu : 1500TimeStamp : 822sec


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MPLS Forwarding Ingress LERRTA

FTN FEC to NHLFE

RTA RTB RTC RTD

10.1.0.0/24 10.2.0.0/24

10.1.1.0/30 10.1.1.4/30

s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

MPLS Domain1

0 .1 . 0 . 0

/ 3 0

.2

.1

1 0

.2

. 0

. 0 / 3 0

.2

.1

FECNHLFE

NextHop Out Interface Label Operation Others

10.2.0.0 10.1.1.2 Serial0 Push

D a t a

1 0 .2 . 0 .1

1030 DataIP

Header


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MPLS Forwarding LSR (RTB)

ILM Incoming Label Map

display mpls lsp include 10.2.0.0 24 in-label 1030 verbose----------------------------------------------------------------

LSP Information: LDP LSP----------------------------------------------------------------

No : 1VrfIndex :Fec : 10.2.0.0/24

Nexthop : 10.1.1.6 In-Label : 1030 Out-Label : 1030 In-Interface : ----------Out-Interface : Serial3 LspIndex : 10256Token : 0x2200cLsrType : TransitOutgoing token : 0x0Label Operation : SWAP Mpls-Mtu : 1500TimeStamp : 11100sec


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MPLS Forwarding LSR RTB

RTA RTB RTC RTD

10.1.0.0/24 10.2.0.0/24

10.1.1.0/30 10.1.1.4/30

s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

MPLS Domain

1030 DataIPHeader

1 0

.1

. 0

. 0 / 3 0

.2

.1

1 0

.2

. 0

. 0 / 3 0

.2

.1


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MPLS Data Forwarding LSRRTC

display mpls lsp include 10.2.0.0 24 in-label 1030 verbose-----------------------------------------------------------------

LSP Information: LDP LSP-----------------------------------------------------------------

No : 1VrfIndex :Fec : 10.2.0.0/24

Nexthop : 10.1.1.10 In-Label : 1030 Out-Label : 1032 In-Interface : ----------Out-Interface : Serial3 LspIndex : 10268Token : 0x22015

LsrType : TransitOutgoing token : 0x0Label Operation : SWAP Mpls-Mtu : 1500TimeStamp : 40sec


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MPLS Forwarding LSR (RTC)

InLabelNHLFE


1030 10.1.1.10 Serial3 SWAP

RTA RTB RTC RTD

10.1.0.0/24 10.2.0.0/24

10.1.1.0/30 10.1.1.4/30

s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

MPLS Domain

1030 DataIPHeader1032

1 0

.1

. 0

. 0 / 3 0

.2

.1

1 0

.2

. 0

. 0 / 3 0

.2

.1


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MPLS Forwarding Egress LERRTD

InLabelNHLFE


1032 10.2.0.2 -------- POP

RTA RTB RTC RTD

10.1.0.0/24 10.2.0.0/24

10.1.1.0/30 10.1.1.4/30

s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

MPLS Domain

1032 Data10.2.0.1

D a t a

1 0 .2 . 0 .1

1 0

.1

. 0

. 0 / 3 0

.2

.1

1 0

.2

. 0

. 0 / 3 0

.2

.1


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MPLS Forwarding Egress LERRTD

InLabelNHLFE


1032 10.2.0.2 -------- POP

RTA RTB RTC RTD

10.1.0.0/24 10.2.0.0/24

10.1.1.0/30 10.1.1.4/30

s0 s0 s3 s2 s3 s3

.2.1 .5 .6 10.1.1.8/30.9 .10

1.1.1.1/32

MPLS Domain

1030 Data10.2.0.1

D a t a

1 0 .2 . 0 .1

1030 Data10.2.0.1 1030 Data10.2.0.11032 1032 Data10.2.0.1

D a t a

1 0 .2 . 0 .1

1 0

.1

. 0

. 0 / 3 0

.2

.1

1 0

.2

. 0

. 0 / 3 0

.2

.1


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Contents

2. MPLS TE

2.1 Introduction

2.2 Concept


2.4 MPLS TE Traffic Protection


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Contents

2. MPLS TE

2.1 Introduction

2.2 Concept




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TE (Traffic Engineering)

NE (Network Engineering)Manipulating the network to suit traffic. Essentially, it is a technologyto plan, design and deploy a network by traffic demand.

TE (Traffic Engineering)

Manipulating the traffic to suit network. Essentially, it is a technologyto control and distribute the traffic for the best resources usage.

Major difference between NE and TEDesign for the disposal of the network or the planning of the traffic

Whether the network exists or not


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Traditional IP TE

R2

R8

R1

R3

R4R5

R6 R7

10 10

10

10

10

Under-utilized alternate path

Path for R2-R3-R4-R5-R8 traffic


All traffic from R1 and R2 to R8 will select the path R3-R4-R5based on the IGP route selection principle


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Traditional IP TE Disadvantage

R2

R8

R1

R3

R4R5

R6 R7

1010

5

5

5

Under-utilized alternate path

Path for R2-R3-R6-R7-R5-R8 traffic


After changing the path Metric, the traffic from R1 and R2 to

R8 will select the path R3-R6-R7-R5.


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Contents

2. MPLS TE2.1 Introduction

2.2 Concept




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MPLS TE MPLS TrafficEngineering

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10



MPLS TE combines MPLS technology with TE. It can make the

network traffic avoid the congestion node to balance the network

traffic, by building a LSP tunnel to the specific destination.


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Contents


2.2 Concept




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MPLS TE Elements

MPLS TE four elements:Information distributionPath calculationSignalingPacket forwarding

Four elements can guarantee basic traffic forwarding, but not veryaccurateMPLS TE also supports some high level specification

FRR Fast Reroute

Tunnel Backup Auto Bandwidth AllocationPath Re-optimization


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Example

MPLS TE

R2

R8

R1

R3

R4

R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0

1.1.1.1 6.6.6.6 7.7.7.7

8.8.8.8

5.5.5.54.4.4.4

3.3.3.3

2.2.2.2


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Basic Configuration EnableMPLS TE

Enable MPLS TE

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0

[R3]mpls lsr-id 3.3.3.3[R3]mpls[R3-mpls]mpls te [R3-mpls]quit[R3]interface s1[R3-Serial1]mpls[R3-Serial1]mpls te


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Basic Configuration ConfigureMPLS TE Tunnel Interface

Setup MPLS TE Tunnel

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0

[R3]interface tunnel 0[R3-Tunnel0]ip add 33.33.33.33 24[R3-Tunnel0]tunnel-protocol mpls te[R3-Tunnel0]destination 5.5.5.5[R3-Tunnel0]mpls te commit


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Information Distribution

What information is distributed?

Link state information (IGP information)

TE Metric

Bandwidth

Administrative Group (Option)

[R3]interface s1

[R3-Serial1]mpls te metric 5


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Information DistributionBandwidth

Bandwidth

Max-Link-Bandwidth

Max-Reservable-Bandwidth

The Max Available Bandwidth For Each Priority

Support 8 tunnel priority 0~7

Support tunnel preemption ,between Different priority

The display the available bandwidth at each

Priority level will be listed for each interface


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Information DistributionBandwidth

Bandwidth

Max-Link-Bandwidth

Max-Reservable-Bandwidth

[R3]interface s1[R3-Serial1]mpls te bandwidth max-reservable-bandwidth 30[R3-Serial1]mpls te bandwidth BC0 20

[R3]interface Tunnel 0[R3-Tunnel0]mpls te bandwidth CT0 20[R3-Tunnel0]mpls te commit


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Information Distribution Priority

Affinity Attributes

Setup Priority

Hold Priority

[R3]interface Tunnel 0[R3-Tunnel0]mpls te priority 7 5[R3-Tunnel0]mpls te commit

Setup Priority is 7

Hold Priority is 5


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When Information Is Distributed?

When MPLS TE information is flooded?

Periodically Flooding (IGP Information)

Link Up Or Down (IGP Information)

Link Configuration Changes (e.g. Link Metric is modified)

(IGP Information)

Link Bandwidth Significant Changes (TE Attribute)

The LSP cannot be set up because of insufficient

bandwidth.


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Information DistributionHow information is distributed?

OSPF-TE

Type 10 Opaque LSA will distributes the link traffic engineering

information

ISIS-TE

Type=135 Wide Metric

Type=22 IS Reachable TLV

By default, OSPF-TE and IS-IS-TE nly support single area.

When deploying TE in multiple areas, we need to configure

Inter-area Tunnels.


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Configure ISIS-TE

[RT3]isis

[RT3-isis-1]cost-style wide

[RT3-isis-1]traffic-eng level-2

Configure IS-ISWide Metric

Attribution

Enable IS-IS TE

Configure ISIS-TE on VRP

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0


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MPLS TE Implementation FlowMPLS TE Implementation Flow

InformationDistribution

Path CalculationPath Setup

Forwarding Traffic DownTunnel


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Path Calculation

MPLS TE use CSPF Constrained hortest Path First

Algorithm

CSPF is an algorithm with constrained conditions. The

constrained conditions include: Cost the same as IGP

Bandwidth

Link Attributes

The path calculation process of CSPF is not designed to find

the best route to every router--but to the tunnel endpoint.


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Configure CSPF

Configure CSPF on VRP

[RT3]mpls

[RT3-mpls]mpls te cspf

Enable CSPF on

each node

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0


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Path Setup

MPLS TE used two types of signaling protocols.

RSVP-TE

Quite mature, and widely used

Base on soft-state, hard to expand

CR-LDP

New protocol, and not so widely used

Base on hard-state, easy to expand


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Check the state of Tunnel

[R3]display mpls te tunnel-interface Tunnel 0

Tunnel Name : Tunnel0Tunnel Desc : HUAWEI, Quidway Series, Tunnel0 InterfaceTunnel State Desc : CR-LSP is Up Tunnel Attributes :

LSP ID : 3.3.3.3:1Session ID : 1Admin State : UP Oper State : UP Ingress LSR ID : 3.3.3.3 Egress LSR ID: 5.5.5.5Signaling Prot : RSVP Resv Style : SEClass Type : CLASS 0 Tunnel BW : 20 kbps

Reserved BW : 20 kbpsSetup Priority : 7 Hold Priority: 7Affinity Prop/Mask : 0x0/0x0.


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MPLS TE Implementation FlowMPLS TE Implementation Flow

InformationDistribution

Path CalculationPath Setup

Forwarding Traffic DownTunnel


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Traffic Forwarding

The Packet forwarding is based on labels. The packet is

forwarded through the pre-established LSP.

How to introduce the traffic into the MPLS TE tunnel?

Static Route

Auto Route

Shortcut

Forwarding Adjacency

Policy Route

h bl f f f


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The Routing Table of R3 Before ConfiguringForwarding Traffic Down Tunnels

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0 S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0

[R3]display ip routing-table 8.8.8.8 32 Routing Table : PublicSummary Count : 1Destination/Mask Proto Pre Cost NextHop Interface

8.8.8.8/32 ISIS 15 30 34.34.34.2 Serial2[R3]display ip routing-table 5.5.5.5 32 Routing Table : PublicSummary Count : 1Destination/Mask Proto Pre Cost NextHop Interface

5.5.5.5/32 ISIS 15 20 34.34.34.2 Serial2

C fi S i R F d


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Configure Static Route to ForwardTraffic

Configure static route to forward traffic on the ingress

node R3 of the tunnel

[R3]ip route-static 8.8.8.8 32 Tunnel 0 preference 10

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0

TE IGP Metric 1

10

C fi St ti R t t F d


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Configure Static Route to ForwardTraffic

The Routing-table of R3 after configuration

[R3]display ip routing-table 8.8.8.8 32 Routing Table : Public

Summary Count : 1Destination/Mask Proto Pre Cost NextHop Interface

8.8.8.8/32 Static 10 0 3.3.3.3 Tunnel0

[R3]display ip routing-table 5.5.5.5 32 Routing Table : PublicSummary Count : 1Destination/Mask Proto Pre Cost NextHop Interface

5.5.5.5/32 ISIS 15 20 34.34.34.2 Serial2


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Shortcut

Configure Shortcut on the ingress node R3 of the tunnel

[R3]interface Tunnel 0[R3-Tunnel0]mpls te igp shortcut isis[R3-Tunnel0]mpls te igp metric absolute 1[R3-Tunnel0]mpls te commit[R3-Tunnel0]isis enable

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0 S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0

TE IGP Metric 1

10


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Shortcut

The routing-table of ingress node R3

[R3-Tunnel0]display ip routing-table 5.5.5.5 32 Routing Table : PublicSummary Count : 1Destination/Mask Proto Pre Cost NextHop Interface

5.5.5.5/32 ISIS 15 1 3.3.3.3 Tunnel0

[R3-Tunnel0]display ip routing-table 8.8.8.8 32 Routing Table : Public


8.8.8.8/32 ISIS 15 11 3.3.3.3 Tunnel0


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Configure Forwarding Adjacency on the ingress node R3

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

[R3]interface Tunnel 0[R3-Tunnel0]mpls te igp advertise[R3-Tunnel0]mpls te igp metric absolute 1[R3-Tunnel0]mpls te commit[R3-Tunnel0]isis enable

10

10

S0 S0

E0

E0 S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2 S0 S0

TE IGP Metric 1


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The Routing-table of egress node R3

[R3-Tunnel0]display ip routing-table 5.5.5.5 32 Routing Table : PublicSummary Count : 1Destination/Mask Proto Pre Cost NextHop Interface

5.5.5.5/32 ISIS 15 1 3.3.3.3 Tunnel0

[R3-Tunnel0]display ip routing-table 8.8.8.8 32 Routing Table : Public


8.8.8.8/32 ISIS 15 11 3.3.3.3 Tunnel0


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Distribute Tunnel Information in R3 ISIS LSDB[R3]display isis lsdb local verbose

Database information for ISIS(1)--------------------------------

Level-2 Link State DatabaseLSPID Seq Num Checksum Holdtime Length ATT/P/OL----------------------------------------------------------------------------0000.0000.0003.00-00* 0x0000007b 0x5d15 573 268 0/0/0

SOURCE 0000.0000.0003.00NLPID IPV4AREA ADDR 49.0001

INTF ADDR 36.36.36.1

INTF ADDR 3.3.3.3INTF ADDR 33.33.33.33+NBR ID 0000.0000.0002.00 COST: 10+NBR ID 0000.0000.0001.01 COST: 10+NBR ID 0000.0000.0006.00 COST: 10+NBR ID 0000.0000.0005.00 COST: 1 .


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Forwarding AdjacencyThe Routing-table of R1 after configuring Forwarding

Adjacency

R2

[R1]display ip routing-table 8.8.8.8 32Routing Table : PublicSummary Count : 1Destination/Mask Proto Pre Cost NextHop Interface

8.8.8.8/32 ISIS 15 21 13.13.13.2 Ethernet0

R2

R8

R1

R3

R4R5

R6 R7

1010

10

10

10

10

10

S0 S0

E0

E0 S1

S1

S2 S2

E0

E0

S2S2

S0S0

S2

S2S0

S0


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Contents


2.2 Concept

2.3 Working Mechanism2.4 MPLS TE Traffic Protection


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Path Protection OverviewPath protection is also called end to end protection, which

establishes backup LSP to protect primary LSP.TE tunnel can be established from source to end, and eachtunnel LSP can pass through different path.

When primary LSP is down, the flow can be switched to

backup LSP tunnel immediately.Backup LSP tunnel should be established in advance, and itwill not bear traffic but reserve bandwidth in ordinarysituation.


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Example for Path Protection

Primary LSP(RTA-RTB-RTD-RTE) is the designated path fromsource to destination.When primary LSP is down, the flow will be switched to backupLSP.Backup LSP (RTA-RTC-RTE) supports two types of Backup LSP:

Hot-Standby LSPOrdinary Backup LSPRTA RTB

RTC

RTD RTEPrimary Tunnel

Backup Tunnel


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Contents

3. VNPT Network3.1 Network Topology

3.2 MPLS and MPLS TE


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Contents




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Contents




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MPLS Design


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Summary

MPLS is using label to do switching, it enhance the reliabilityof the network due to connection forwarding plane.

MPLS TE solve the TE issue which face by IP network.


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(1.3) MPLS and MPLS TE Principle and Deployment in VNPT

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