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Copyright(c) 2011 P1

MPLS-TP:Overview and status

Yoshinori Koike

OFC/NFOEC 2013

Optical Network Applications and Services (Tutorial)

March 20, 2013

978-1-55752-962-6/13/$31.00 2013 Optical Society of America

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Agenda

1. Drivers of packet transport technologies and their applicability

2. Definition of MPLS-TP

3. Layer 2 technologies

4. Additional functions in MPLS-TP

5. History of MPLS-TP standardization

6. Deployment scenarios of MPLS-TP technology and network

7. Promising multi-layer converged transport network

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1. Drivers of packet transport technologies and theirapplicability

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Promising packet transport network

Reduction of CAPEX/OPEX => Ethernet-IF, low power consumption,

Multi-service => Various clients (Ethernet, SDH, PDH, ATM,

MPLS

Traffic engineering/ => Traffic engineering

Recovery => Protection

Carrier grade operation => OAM, transport-oriented operation

Guarantee of quality => QoS

Timing distribution => SyncE, time & phase distribution

Characteristics of packet transport network

As IP services drastically increase, Carriers and ISPs have been willing to efficientlyaccommodate their client traffic. Packet networks have been rapidly expanding.

Following this demand, Ethernet and MPLS have been introduced to their networks;however, they did not have sufficient maintenance capabilities such as troubleshooting, and alarm reporting.

Current transport technologies, such as SDH and OTN, equip carrier grade OAM andprotection.

This results in strong demand for packet transport technology in carrier networks.

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Applicability of packet transport technologies

Mobile NW

Home NW

Business customers NW

Access NW Metro/aggregation NW Core NW

PTN

VoD, SIP

IP-TV

Packet transport technologies could fit and be introduced into any part of anetwork from access, metro/aggregation and core.

For example, one scenario is to keep IP/MPLS core network and introduceMPLS-TP into metro network.

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2. Definition of MPLS-TP

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Relationship between MPLS and MPLS-TP

Existing MPLS

Before standardization

of MPLS-TP

ECMP

LDP/Non-TE

LSPs

IP forwardingPHP

Common features

MPLS forwarding

PWE3 architecture

ECMP: Equal Cost Multi Path

PWE3Pseudo Wire Emulation Edge to EdgePHP: Penultimate Hop Popping

MPLS-TP (Transport Profile) consists of MPLS technology excluding

unwanted functions and additional functions from transport technologies

such as SONET/SDH.

Additional functions

from transport

technologies

Extensions of existing MPLS

such as RFC6374 (delay and loss)

and RFC5586 (G-ACH)MPLS

MPLS-TP

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MPLS TP operation and protectionNMS management

Psudowire (static or dynamic)

MPLS-TP LSP (static or dynamic)

section section

Client traffic

Customer Edge

Client NE

P

NE

PENEPENE

ProtectionWorking LSP

Protection LSP

Permanent Bridge Selecter Bridge

Customer Edge

Client NE

C-plane(option)

C-plane(option)

C-plane(option)

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Client accommodation (Pseudewire technologies)

Pseudowires (PWs) accommodate/adapt multi-technology clients, such as

Ethernet/SDH/ATM, in MPLS-TP

In other words, PW is a mechanism to emulate telecommunication services

such as Ethernet, ATM, SDH, and dedicated line in MPLS-TP network

PW label

LSP label

PW

Payload

PW based

service

Dedicated lineEthernetSDHATMFR etc

MPLS-TP layer

Client layer

CE1 CE2

CE: Customer Edge

PE: Provider Edge

PE1 PE2

TunnelLSP

PW segment

Emulated service section

AC

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Client accommodation (Pseudewire technologies) Contd.

PWE3 is extended to single segment PW to multi-segment PW. It may be

possible to swap tunnel protocols in PW layer.

There is some discussion about whether overlapping of MS-PW switching

function is necessary.

PW label

LSP label

PW

Payload

MPLS-TP

Layer

Client

layer

PWE

MPLS-TP layer

PW label

LSP label

PW

Payload

PWE

Client layer

S-PE T-PE2T-PE1

Multi segment PW

T-PE: Terminating Provider Edge

S-PE: Switching Provider Edge

CW: Control Word

PW label switching

(Swapping)

10 60CWPayload 20 80CWPayload

Multi-segment PW model

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3. Layer 2 technologies

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Difference in original concept of data-plane between Ethernet and MPLS

Ethernet data-plane is originally capable of automatically establishing MP2MP topology and

connectionless technology based on MAC learning and bridging.

VLAN-tag was introduced after MAC learning and bridging and defined for boundary of

broadcast domain (not allowed to be swapped in terms of standardization).

MPLS is capable of establishing P2P and P2MP connection-oriented technology. MPLS label is

originally designed for swapping.

Label TC S TTL

DA SA S-tag C-tag T/L

S-VID

DEIPCP

Ethernet

MPLS(-TP)

VLAN

-1

VLAN

-2

VLAN

-3

MPLS

router

2010

Label swapping is

standardized

Tag is used as User

Identification and

definition of broadcast

domain

Tag swapping is not

standardized

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Comparison between Ethernet and MPLS

Ethernet MPLS

1 Multi-point to Multi-point Yes No

2 Data-plane auto-discovery Yes (MAC learning

and Bridging)

No (needs C-plan)

3 Swapping in terms of

standardization

No (VLAN-tag) Yes (LSP label)

4 Number of layers C-tag, S-tag, I-tag, B-

tag

Label stacking

5 Client support Ethernet, SONET/SDH Ethernet, SONET/SDH,

PDH, ATM, Frame relay

6 Possibility of looping in data-

plane

High Low (in static)

7 Make-before-break No Yes

Ethernet is applied for automatic MP2MP topology establishment as well as P2P/P2MP

topology establishment.

MPLS is applied for explicit provisioning of P2P and P2MP connection, particularly for trafficengineering feature.

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Comparison between MPLS and MPLS-TP

Management-plane (NMS)-based central operation is key feature not supported by original

MPLS (RFC5654 R17&19).

Independence between data-plane and control-plane is another key feature in MPLS-TP

(RFC5654 R23&47).

MPLS-TP will be included as part of MPLS in near future, but MPLS and MPLS-TP are technically

different at moment. Many common parts can be seen in data-plane. Regarding OAM, MPLS

and MPLS-TP are quite different, and interoperability is almost impossible.

Difference between MPLS and MPLS-TP

in data-plane and OAMData-plane/Transport-plane

Current MPLS MPLS-TP

IP forwarding, label

merging, PHPProtection

Label

Forwarding

OAM (OAM identification)

Label 13

(GAL) G-Ach

Label 14

IP encap

VCCV

Item MPLS MPLS-TP

No control plane No Yes

Separation between

C-plane and D-plane

No Yes

NMS-based central

management

No Yes

Protection No Yes

Label 13 (GAL) No Yes

Different characteristics between MPLS and MPLS-TP

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One aspect: MPLS-TP in core transport network

Ethernet is superior in terms of MPtoMP aspects and easy connectivity. Reliability is guaranteed

based on OAM extension to some extent.

MPLS(-TP) is more reliable and suitable in terms of its original traffic engineering concept. It

does not rely on MAC learning or FDB flashing.

MPLS-TP is very useful in core transport network if functions of transport network are required

for reliability and enhanced maintenance capability

IP/MPLS

or MPLS-TP

EthernetMPLS-TP

An example of MPLS-TP applicability

Ethernet

(PBB

Metro/Aggregation NW

Ethernet

(PBEthernet

(PB

Core transport network

Metro/Aggregation NWMetro/Aggregation NW

Provider

Backbone

Bridge NW

(IEEE802.1ah)

Provider Bridge NW

(IEEE802.1ad)

Provider Bridge NW

(IEEE802.1ad)

NMS

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4. Additional functions in MPLS-TP

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Effective maintenance capability: Prompt fault localization

Carrier grade means extending maintenance features and operational tools ratherthan adding new service functions for our customers in transport service

After starting to provide our services, quality of maintenance service is only factordefining value of carrier.

Prompt fault localization is one of most essential factors, i.e., to identify what isgoing on, and where, when, and how it happened.

P1 CustomerNE2

Customer

NE1

Customer domainCustomer domain

P2 P3 P4 P5 P6

Carriers domain

Mis-

configuration?Traffic

overload?

Unexpectedfault? Unidentifiedglitch?

Lot fault?

Customer

misconfigura

tion

Equipment

fault

MemoryError?

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1) New maintenance model: Per-interface model

Existing MPLS

(Per-node model)

Newly supported in MPLS-TP (Per-interface model)

Ingress Egress

MIP

MEP

MIP

Source/Destination

node

MEP

Intermediate node

MIP

out

MIP

InFW

Down

MEP

UpFW MEP

UpDownFW

Intermediate node

Source/Destination

node

Source/Destination

nodeFW: Forwarding Engi

Per-interface OAM model is supported for improving maintenance.

Traffic monitoring is possible with both Ingress IF and Egress IF cards in one box.

Fault localization capability is significantly improved compared to current MPLStechnology.

Refer to: ITU-T G.8121 G.8151 RFC6371 and draft-

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Case 1) Difference in fault location scenario between two approaches

:Packet loss at Customer NE

P1

(1)

(2)

NE2 NE3NE1

Customer

NE2

Customer

NE1

PW/LSP

MEP1 MEP2


MIP1 MIP2 MIP3 MIP4

P3 P5

PW/LSP

MEP1 MEP2MIP1

OK

OK

OK

P1Customer

NE2Customer

NE1


P2 P3 P4 P5 P6

? ? ?

OK OK ?

Packet LossPacket

Loss

Operators

Administrative domainPer-node model

Per-interface model

MIP

MEP

Legends

Interface

Forwarding

Engine

On-demand CV

On-demand CV

NE2 NE3NE1

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Case 2) Difference in fault location scenario between two approaches

P1

(1)

(2)

Customer

NE2

Customer NE1

PW/LSP

MEP1 MEP2


MIP1 MIP2 MIP3 MIP4

P3 P5

PW/LSP

MEP1 MEP2MIP1

NG

NG

OK

P1Customer

NE2

Customer NE1


P2 P3 P4 P5 P6

? ? ?

OK ? ?

Operators

Administrative domainPer-node)

Per-interface)

Packet LossPacket

Loss

MIP

MEP

Legends

Interface

Forwarding

Engine

On-demand CV

On-demand CV

NE2 NE3NE1

NE2 NE3NE1

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Case 3) Difference in delay measurement scenario between two approaches

P1

MIP

MEP

LegendsInterface

Forwarding

Engine

Customer NE2CustomerNE1

PW/LSP

MEP

1

MEP

2


MIP1 MIP2 MIP3 MIP4

P3 P5

PW/LSP

MEP

1

MEP

2MIP1

P1 Custom

er NE2

Customer

NE1


P2 P3 P4 P5 P6

Operators

Administrative domain

Per-node)

Per-interface)

Measurable section

Measurable section

Delay of this

section is not

measurable

Operators


NE2 NE3NE1

NE2 NE3NE1

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Distinction between communication and equipment alarms

On-demand

CV

(1)

(2)

(3)(4)

(5)

Type 1

(MPLS-like)

MIP

MEP

Legends

Interface

Forwarding

Engine

NE2 NE3NE1

Equipment

alarmCommunication

alarm

Type 2

(TDM-like)

YES

YESYES

YES

YES

Operators


General alarm classification

in transport network

Custom

er NE

YES

YES

No

No

No

Clear definition of ingress and egress MPs makes operational system followtransport characteristic and makes it possible to precisely investigate LSP status forcustomer service.

Status of equipment (NE) largely depends on forwarding engine. That ofcommunication part (between NEs) mainly depends on interfaces.

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2) Hitless/in-service path segment monitoring

Segment monitoring function is necessary in Delay Measurement (DM) andLoss Measurement (LM)

(DM and LM are supported only between MEP and MEP, not supported

between MIP and MEP/MIP)

: See use case 1 on next slide

Diagnostic test and on-demand CV should also be able to be conducted fromintermediate point of configured transport path.

: See use case 2 on next slide

There is no requirement and solution in standard which make it possible to locate

degraded point in hitless manner/without service interruption when performance

degradation is detected.

Hitless and temporal segment monitoring is on-demand OAM function to quickly

localize degraded point, which is under development in standard.

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Use cases of hitless segment monitoring

NE1(LER1)

CE2CE1

NE2(LSR1) NE4(LER2)NE3(LSR2)

Packet

Delay/Loss

Segment monitoring 1

Transport path


No Fault

Detect Fault

Use case 1) DM and LM

Use case 2) Diagnostic test and on-demand CV

NE2(LER1)

NE5NE1

NE4(LER2)NE3(LSR2)



Originator of

test packets

Cost effective small box

(Support subset of functions)

MEP

MEP

MIP

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5 History of MPLS-TP standardization

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Type of Recommendation Common Only for PTN Only for PSN

Architecture

OAM

Interface

Linear protection

Ring protection

Equipment functional block

Equipment management

requirements

Equipment management info model

(mgmt protocol independent)

DCN

Terms and definitions

Current status of ITU-T MPLS-TP-related Recommendations

G.8110.1

G.8112*

G.8113.1

G.8121*

G.8131 (or G.8131.1&G.8131.2)

G.8132

G.8151*

G.8152

G.8101

G.7712

Approved RecommendationsPTN: Packet Transport Network

PSN: Packet Switch Network(IP/MPLS)

AAP: Alternative Approval Process

TAP: Traditional Approval Process

* Revised as MPLS-TP from T-MPLS

G.8113.2

G.8121.1 G.8121.2

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Progress of MPLS-TP OAM standard

2008: Joint work on MPLS-TP standardization was agreed in 2008.

Two communities of interest advocated different approaches to develop MPLS-

TP OAM solution: ( G.8113.1 (Ethernet-based OAM) and G.8113.2(IP/MPLSbased OAM).

Feb. 2011: G.8113.1 was determined in ITU-T by vote.

Nov. 2011: G.8113.2 based OAM solutions became RFCs, and G.8113.1-based

OAM solution was not allowed to progress in IETF due to lack of rough

consensus.

Dec. 2012: Deadlock on MPLS-TP in ITU-T SG15 meeting was partially broken

by approving G.8110.1 by consenting to G.8121 and G.8151. However,

G.8113.1 was escalated to WTSA-12.

Sep. 2012: G.8113.2 was determined and also sent to WTSA-12. Both meeting

recommendations were sent to WTSA-12 for approval.

Nov. 2012: Both G.8113.1 and G.8113.2 were approved in WTSA-12 and code

point for G.8113.1 was assigned by IANA

Both G.8113.1 (Ethernet based OAM) and G.8113.2 (IP/MPLS

based OAM) have been standardized.

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How to differentiate OAM protocol solutions?

Label Value |TC|S|TTL GAL(13) |TC|S| TTLACH-TLV

Header

LSP label

GAL

ACH

ACH-TLV

Generic Associated Channel Label

(LSP label identifying OAM packet : label value 13),

Associated Channel Header (same as PW ACH but generalized)

Channel Type defines OAM protocol solution

ACH-TLV (Option, Src/Dst address, Authentication, etc.)

G-ACh message (depending on each OAM protocol solution using

G-ACh)G-ACh Msg.

MPLS label header

32 bits 32 bits 32 bits

0001|ver |rsv|Channel Type

MPLS-TP OAM protocol solutions: Generally differentiated by channel type

in extended Associated Channel Header(ACH)

Some MPLS-TP OAM protocols use other channels, such as existing PW ACHand IP encapsulation,

ACH-TLV

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OAM functional requirements in MPLS-TP (RFC5860)

OAM functions are most important key MPLS-TP technologies to achieve carrier grade

operation in transport networks

OAM functional

requirement

Abbr. Function

1 Continuity Checks CC Monitor liveliness of transport path

2 Connectivity

Verifications

CV Determine whether or not it is connected to specific end

point(s) of transport path

3 Route Tracing RT Discover intermediate (if any) and end point(s) along transport path

4 DiagnosticTests

DT Conduct diagnostic tests on transport path(estimating bandwidth, performing loop-back (LB) function of all data and OAM traffic

(data-plan LB))

5 Lock Instruct LI Instruct its associated end point(s) to lock transport path

6 Lock Reporting LR Report lock condition from intermediate point to end point of transport path

7 Alarm

Reporting

AR Report fault or defect condition to end point of transport path

8 Remote DefectIndication

RDI Report fault or defect condition to its associated endpoint

9 Client Failure

Indication

CFI Propagate information pertaining to client defect or fault condition

10 Packet Loss

Measurement

LM Quantify packet loss ratio over transport path

11 Packet Delay

Measurement

DM Quantify delay of transport path (1-way and 2-way)

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Mappings between RFC and Recommendations on OAM solution

ITU-T MPLS-TP

OAM

Recommendations

OAM solution RFC Channel type Status

1 PTN

G.8113.1

None:

(Discussed in draft-bhh-mpls-tp-oam-y1731)

0x8902 G.8113.1 -

(I-D)

2 PSN

G.8113.2

MPLS Fault Management Operations,

Administration, and Maintenance (OAM)

0x0058 Fault OAM RFC6427

3 Proactive Connectivity Verification, Continuity

Check and Remote Defect Indication for the MPLS

Transport Profile

0x0022 MPLS-TP CC message

0x0023 MPLS-TP CV message

RFC6428

4 MPLS On-demand Demand Connectivity

Verification and Route Tracing

0x0025 On-Demand CV RFC 6426

5 Packet Loss and Delay Measurement Profile for

MPLS-based Transport Networks

(profile of draft-ietf-mpls-loss-delay)

0x000A DLM

0x000B ILM

0x000C DM

0x000D DLM+DM

0x000E ILM+DM)

RFC6375

(RFC6374

)

6 MPLS Transport Profile Lock Instruct and Loopback

Functions

0x0026 LI RFC6435

One I-D (Doc. No6) corresponds to G.8113.1(PTN OAM) was submitted as I-D ,

but solution was not allowed for developing in IETF

5 MPLS-TP OAM solution drafts are related to G.8113.2(PSN OAM) in G.8113.2

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Differences between PTN OAM and PSN OAM solutions

1. G.8113.1

G.8113.1(PTN) OAM solution focusing on MPLS-TP OAM-specific requirements based on Ethernet

OAM mechanism

G.8113.2(PSN) OAM solution covering IP/MPLS-oriented requirements for compatibility

2. RFC6427

(Fault OAM )

5. RFC6375 (DLM, ILM, DM, DLM+DM, ILM+DM)

4. RFC6426 (On-Demand CV)

3. RFC6428 (CC message and CV message)

6. RFC6435 (Li)

IP/MPLS Requirements

4 channels (G-ACH, VCCV(v4 and v6), UDP/IP

2 mode of operations ( Independent and fate sharing)

Link Down Indication

Configurable message transmission interval

Configurable message fault detection interval

Timer negotiation

In-service parameter change (P/F bits)

Configurable message transmission interval

LM&DM combined modes (Direct and inferred packet loss and delay measurements)

Two types of LM formats (32 and 64 bits) Two types of DM formats (PTP and NTP)

4 channels (G-ACH, VCCV (v4 and v6), UDP/IP

Return codes Target FEC stacks Downstream mapping

LSP ping ext

CC/CV interleaved (CV only is not possible and

interval is only one per second)

MPLS-TP OAM Requirements

CC

CV

RDI

AR

DMLM

RT

LR

DT (DP-LB)

CV

DMLM

LI

DT(Thrpt 1)

On-demand OAM functions

Proactive OAM functions

IP/MPLS requirements

OAM solutions for PTN

OAM solutions for PSN

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Differences between MPLS-TP OAM Recommendations

Two OAM solutions G.8113.1

(PTN: Y.1731 based OAM)

G.8113.2

(PSN: Extension of BFD&LSP

Ping +performance)MPLS-TP OAM

requirements

YES

(except for LI and Data-

plane LB)

YES

Characteristics as tool(s) Simple

(Transport experience)

Easily extended from IP/MPLS

router(Control experience)

Preferred compatibility Ethernet OAM IP/MPLS OAM

PTN:

Used to add packet transport capability to existing circuit switched (SDH/OTN) transportnetworkPSN:Used to provide packet transport capability to existing IP/MPLS network

Differences between two stem from differences in history, architecture,

technology, and previous experience.

Ethernet and IP/MPLS are two different major drivers for transport networks.Operators can choose necessary OAM solution on basis of their network

development scenarios.

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Typical scenario for PTN: Replacing legacy transport network

Legacy network (SDH etc.)

MPLS-TP network

NMS

NMS

Ethernet

ATM

PDH

SDH

Migration from legacy transport network Co-routed bidirectional PtoP.

Optionally Unidirectional PtoMP.

Suitable with Ethernet/transport-based OAM

Scalable OAM, easy operation and

centralized NW management system

(similar to legacy transport NMS)

No need of IP layer and IPfunctions

Ethernet

ATM

PDH

SDH

Replacing legacy Nodes

Transport node with MPLS-TP

Transport node without MPLS-TP

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PE router

Typical scenario for PSN: Upgrading/extending IP/MPLS router

Ethernet

IP/MPLS

Ethernet

IP/MPLS

Co-routed/Associated

bidirectional PtoP, Unidirectional

PtoP, and PtoMP.

Compatible OAM with IP/MPLS

and PW such as LSP-Ping, MPLS-

BFD, VCCV, and VCCV-BFD

IP layer and IP functions

necessary for LSP ping at leastPE router

P router P router

PE router

PE router

IP/MPLS upgrade/migration

Upgrading P routers/

Replacing P routers

P router with MPLS-TP

P router without MPLS-TP

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Summary of possible deployment scenarios

Two MPLS-TP deployment scenarios are introduced.

Ethernet-friendly approach and IP/MPLS-friendly approach are considered. (Called PTNand PSN, respectively)

Scenario General prioritized preference Type

1 -Transport network experience (Ethernet OAM)

-Static and centralized configuration

-Could be extended to converged NW operation

mainly based on management plane

PTN

2 -IP/MPLS compatibility (BFD, LSP Ping)-Dynamic and distributed configuration

-Could be extended to converged NW solution mainly

based on control plane

PSN

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7. Promising Multi-layer converged transport network

Solution: Multi-layer and multi-technology convergence:

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Solution: Multi layer and multi technology convergence:

NW optimization and NE convergence

MPLS-TP makes transport networks flexible and more efficient

100G interface introduction is driver for drastically changing network

structures to reduce cost in conjunction with energy efficiency

Optimization of entire transport network is key to achieve objectives

Minimized multi-layer and multi-technology converged transport networks are

promising solution

Current 100G based on POTSEdge IProuter/

switchMany 10G

wavelengths and

fixed bandwidth

Many kinds of

network

systems

Many inter-

connections by

many

EMS/NMS

(2)Easy operation by

converged equipment by

fewer EMS&NMS

(1) Minimized multi-

layer and multi-

technology converged

transport networks

Relay

router/

switch

WDM/

OADM

POTS

Edge IP

router/sw

itches

Edge IProuter/

switch(3) Large capacity physical link and

adaptive and efficient bandwidth

allocation by packet transport

Many inter-

connections due

to many

EMSs/NMSs

(2) Easy operation with

converged equipment

and fewer EMSs & NMSs

POTS

1) E ample of red ction of core ro ter/s itches

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41

1) Example of reduction of core router/switches

DWDM

CR

CR

DWDM

DWDM

CR

CR

DWDM

DWDM

DWDM

DWDM

DWDM

DWDM

DWDM

POTS POTS

POTS POTS

POTS POTS

ER ER ER ER

Router 100G-IF

NNI 100G-IF

3R-NNI 100G-IF

Packet IF100G-IF

Optical SW

Optical SW+ Packet SW

In NW model below, 50% reduction in equipment cost may be possible by

applying packet optical transport solution.

Main factors are router equipment and IF cost reduction. Other costs, such

as enhanced OAM and operating system, are not included in estimate.

Future packet optical transport networkCurrent network

100About 50%

2) Example of topology-free flat transport network

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42

2) Example of topology-free flat transport network

DWDM

DWDMPOTS

DWDM

DWDM

OADM OADM

OADM OADM

OADM OADM

OADM OADM

POTS

POTS POTS

POTS POTS

POTS POTS

Operator

Topology-free flat transport networks enable operators to efficiently and simply set

path for client equipment.

This improvement may depends on current network structure of each operator.

Operator 1

Operator 2

1. Several operators(NMSs/EMSs) to one

operator (NMS/EMS)

2. Manual design in

several layers and

domains to

automatically design

in converged layers

3) Example of unified fault and degradation management across layers

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43

3) a p e o u ed au t a d deg adat o a age e t ac oss aye s

Layer-independent NW Multi-layer converged network

Virtual switch unit

Physical switch unitInteraction between layers would

make fault detection time shorterFault detection

Efficient fault localization is key feature in multi-layer converged network managed

by unified NMS.

Inter-layer (or Inter-protocol) relationship, in particular OAM, is also important:

Quick fault localization by inhibiting alarm storms, quick recovery of efficient AIS andso on.

No relationship

between layer

dependencyRoot fault

4) Example of unified network resource management

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4) Example of unified network resource management

POTS POTS

Layer 2

(packet)

Layer 1

(ODU)

Layer 0

POTS POTS POTS

L2

SWLayer 2

Layer 1

Layer 0

L2

SW

L2

SW

L2

SW

L2

SW

SDH SDH SDH SDH SDH

WDM/

ROADM

WDM/

ROADM

WDM/

ROADM

WDM/

ROADMWDM/

ROAdM

Future packet optical transport networkCurrent network

Efficient resource design tool prevents consumption of wasteful

bandwidth and network resources across layers.

ODU layer (layer 1) cross-connect or packet layer (Layer 2) switching canbe omitted based on situation.

Summary

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Summary

Increasing demand for packet transport technology was driver for

MPLS-TP technology

Key features of MPLS-TP:

Separation of Data-plane and Control-plane

OAM

NMSRecovery (Protection)

An OAM solution (G.8113.1(PTN) ) has been standardized. PTN isa simple and transport-oriented OAM solution based on Ethernet

OAM.

Converged transport network solution based on MPLS-TP is apromising solution for future cost & energy efficient networks

Date post:	03-Jun-2018
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