21407- Transport MPLS Rationale and Features Final v3 DS0110

Transport MPLS Rationale and Features

Alberto Lometti

February, 2007

2 | Transport MPLS Rationale and Features | February 2007 All Rights Reserved © Alcatel-Lucent 2006, 21407

Agenda

1. T-MPLS Rationale2. T-MPLS Features3. T-MPLS Standard Status & Perspectives4. T-MPLS Applications5. Conclusions


1 T-MPLS Rationale


TDM/WDM-based

networking

Packet/cell/

frame based

networking

Reliability, availability,OAM in service delivery

Scalability and granularity

Service delivery throughpacket-based technologies

+ PacketTransport Networking

Transport network evolution (min cost) with

(max carrier-class& flexibility)

Services

Service EvolutionNetworking

Requirements

Why a Packet Transport Network?

Triple Play Business Services

Migrating to data-orientedleased lines, virtual private LANs

Mobile Service Operators

Converging transport of radio acc., pt-to-pt mw, NGN services…

Driving withHSI, video, voice

Debby Schryer

1.White box on bottom left: I think should be:Ethernet/ATM/frame relay-based networking2. The blue triangle in the middle doesn't make sense with the parentheses the way they are. I'm not sure what the correct version should be.


Packet Transport Network: Requirements Being client-agnostic (able to carry L3, L2, L1) Being strictly connection-oriented Implementing strong OAM capabilities, similar to those available in

existing transport networks (e.g., SDH) Implementing both service and line resilience mechanisms, similar

to those available in existing transport networks (e.g., SDH) Allowing for network provisioning either via a centralized

management tool and/or a distributed CP Allowing for homogeneous and/or unified management and

control of transport network when different layers are present at the same time

These requirements are the basis of ITU T-MPLS design.

Debby Schryer

I changed the bottom statement from "at the basis" to what you see here. A lot of this text is not quite standard English, so I'm trying to adjust for that.


Expanding the Transport Network Architecture with Packets

Management Plane

Control Plane

Data Plane

Survivability (Protection, Restoration)

OAM

SDH LayersFraming, Forwarding,

Encapsulation

OTN/WDM LayersFraming, Forwarding,

Encapsulation

T-MPLS LayersFraming, Forwarding,

Encapsulation

Common multilayer operations, survivability, control and management paradigms for packets, circuits & photonics


2 T-MPLS features


Transport MPLS (T-MPLS) in BriefTransport MPLS is a connection-oriented packet transport technology, based on MPLS frame formats. It reuses the most widespread label swapping paradigm existing in telecom. It inherits all IETF definition activity in terms of server and client

encapsulation rules. It profiles MPLS so that it avoids the complexity and need for IP routing

capability.Transport MPLS defines powerful OAM capabilities that enable status & performance reports, in such a way that they remain confined within the T-MPLS layer and do not require deeper packet inspection. It allows for guaranteed SLAs. It defines protection switching and restoration. It allows for efficient fault localization and multi-operator service offering.A Transport MPLS layer network is operated with network management and/or by a control plane. The control plane inside the T-MPLS network is GMPLS.

Debby Schryer

I don't think the statement in red says what it is supposed to mean. ???


MPLS and T-MPLS

MPLS frame, forwarding, encapsulation

OAM OAMSurvivability Survivability (G.808.x, G.8080)

Control Plane (IP/MPLS/(GMPLS)) Control Plane (GMPLS/ASON) Management Plane Management Plane

Transport NetworkPSN

IP frame, forwarding,

encaps.

T-MPLS

Circuit frame, forwarding,

encapsulation (SDH, OTH)

No penultimate hop popping• Is not in line with an L2 confined OAM

No merging• Would not allow an L2 confined OAM

per connection No equal cost multipath (ECMP)

• Would imply frame re-ordering Adds bidirectional LSPs

• Typically used in transport contexts

TMPLS is:•Strictly connection-oriented•Strictly L2-bound (it does not need any IP for data plane, e.g. OAM)•Homogeneous with other transport layers (SDH, OTH) as regards basic network features, i.e. OAM, protection, (optional) control plane, management plane

Debby Schryer

Please confirm "hop popping"


Client D

Client A

Clie

nt C

Clie

nt B

Clie

nt C

T-MPLS network model

Clie

nt B

Client A

Client D

Clients: in T-MPLS it can be any L2, using

mapping options defined by IETF for

PWE3: Ethernet, ATM, FR … ) or IP/MPLS (so

far only Ethernet formally defined in

ITU)

Physical connection: in

T-MPLS it can be any L1 (Ethernet, SDH, OTN+WDM …);

moreover in T-MPLS an optional section layer is under definition, in order

to support OAM if not otherwise available

Logical connection: in TMPLS two networking

layers are under definition: circuit

(equivalent to IETF PWE3) and path

(equivalent to IETF MPLS tunnel)

Logical connection: inT-MPLS two networking

layers are under definition: circuit

(equivalent to IETF PWE3) and path

(equivalent to IETF MPLS tunnel)

T-MPLS equipment(switching capability

either at circuit or path layer)


T-MPLS Survivability

Protection (data plane) <50 ms with automatic protection

switch (APS) protocols on data plane OAM channels

1+1, 1:1, N:1 (no extra traffic) Unidirectional, bidirectional Section, path, circuit Subnetwork connection (SNCP) Ring Dual node interconnect (DNI)

T-MPLS

Client Equipment

Restoration (control/management plane)

Distributed control plane (ASON/GMPLS)

Full LSP rerouting restoration Pre-planned LSP rerouting restoration Any topology (mesh) GMPLS-based restoration in synergy

with other transport network technologies (SDH, OTN, WDM)

RingProtect

DNI

Circuit & PathProtection

Section Protection

Client Equipment


T-MPLS OAMTransport service functional model

Client

Client

Non-intrusive monitoring

integrity check connectivity check quality check

TerminationLike non-intrusive mon. + backward integrity info backward quality info

LogicalConnection

Client-server adaptation

forward defect indication

Connection forwarding grooming

PhysicalConnections

Client-server adaptation

forward defect indicationTermination

Like non-intrusive mon. +

backward integrity info backward quality info

Debby Schryer

Small black lines from text boxes to colored parts of the graphic should not cross the borders of the colored graphic items. They should just lead to the graphic item and then stop. They should also be straight wherever possible.See green items on the bottom left, red on the left middle, and orange and blue on the right.


Fiber

Protection Integrity IntegrityConnection ConnectionQuality Quality

Remote integrityRemote quality

Maintenance

Integrity IntegrityConnection ConnectionQuality Quality

Silencing Integrity Integrity Silencing IntegrityCongruence Congruence CongruenceConnection Connection ConnectionQuality Quality QualityRemote integrity

Remote integrity

Remote quality Remote qualityQuality Measurement



Remote integr.Remote quality

ClientLogical ConnectionPhysical Connection

T-MPLS OAMSimplified network model & basic OAM tools


T-MPLS OAM

OAM primitives

T-MPLSY.1711 - Y.17tom

Continuous On demand

Integrity FFD, CV Loopback

Connectivity FFD Link Trace(ffs)

Quality PM (carried by FFD)

Frame Loss, Frame Delay, FDV

Remote integrity BDI Loopback

Silencing FDI Not applicable

Standardized

Ongoing


T-MPLS OAM according to ITU is contained in MPLS frames associated to the connection by the relevant LSP (outer) label and characterized by an (inner) label 14.

OAM information is contained within the MPLS payload.

Fiber (i)

ClientLogical ConnectionPhysical ConnectionProtection FFD Server specific

FFD (via TTSId) Server specificPM Server specificBDI Server specific

Server specificMaintenance

Client specific CV, FFDClient specific Link TraceClient specific PM

Silencing CV, FFD CV, FFD FDI Server specificCV, FFD CV, FFD Server specificPM PM Server specificBDI Server specificRemote quality Server specific

Quality Measurement

Client specific CV, FFD,Client specific CV, FFDClient specific PM

Client specific CV, FFD,Client specific CV, FFDClient specific PM

BDIRemote quality

T-MPLS OAM(according to ITU-T Y.1711, Y.17tom)


T-MPLS Control Plane (ASON/GMPLS)

GMPLS is a single, generalized distributed control plane that can be used in common for multiple networking technologies, including packets, TDM and photonicsGMPLS defines: UNI concept (thus easing overlay dynamic approach) I(nternal)-NNI concept (the only supported in MPLS CP) E(xternal)-NNI concept (thus allowing for interworking among different

vendors/operators) Bidirectional pathsGMPLS allows for separation of data plane and control plane Only control interfaces are used to flood control informationGMPLS allows for “horizontal” scalability in routing domains (thanks to separation of data plane and control plane and recursive topology)GMPLS allows for “vertical” scalability (same control plane across different layers)

GMPLS is the ideal control plane for multilayered networks

Debby Schryer

See colored text. Not sure what it means.


3 T-MPLS Standard Status & Perspectives


Protection G.8131OAM Y.17tom

GMPLS ProtocolsControl Plane &

Restoration(IETF)

T-MPLS Standards Framework

MPLS Architecture/

Protocols(IETF)

Carrier-grade packet forwarding best from IETF

Carrier-grade control planebest from IETF

TMPLSFramework

Contribute

T-MPLS InterfacesG.8112

T-MPLS EquipmentFunctional Blocks

G.8121Architecture of T-MPLS Layer

Network G.8110.1ASON Architecture

G.8080

Best from ITU


Transport Network Standard Overview

T-MPLSstandard status

Version 1 approvedAmend. 1 (p2mp, extended OAM) to be consented Mar-Jun07

Version 1 approvedAmend. 1 (p2mp) to be consented Mar-Jun07Y.1711 approvedY.17tom (ext. OAM, TC) to be consented Apr07Version 1 approvedAmend. 1 (p2mp, protection) to be consented Mar-Jun07

Y.1720 approvedG.8131 v1 (adaptation to T-MPLS) consented

Amend. 1 (ring) to be consented Jun07

SDH OTH T-MPLSC.O. G.805C.L. G.809

G.873.2 (frozen)

G.808.2(frozen)

Y.17tom (Y.1711)

G.8121 (G.mplseq) G.806

G.808.1

----

G.8131 (Y.1720)

G.803 G.872 G.8110.1

G.841

G.709

G.8132Ring Protection

Linear Protection G.873.1

Network Architecture

Equipment G.783 G.798

UNI & NNI Interface

OAM [frame format]

G.707

Connection Oriented(G.805) Generic

C.O. + C.L.

G.uftan

G.8112 (G.motnni) ----


4 T-MPLS Applications


T-MPLS: Implementation for Interworking Transport and service instances in a transport node

MultilayertransportnetworkService

InstanceTransportInstance

STP (NM, GMPLS) Ethernet GMPLS (or NM) T-MPLS GMPLS (or NM) SONET, SDH GMPLS (or NM) ODU GMPLS (or NM) CP technology DP technology

A border node has “service

instances” and “transport instances.”

An inner node has only

“transport instances.”

OuterT-switch

InnerT-switch

(MS)-LDP

LDP, RSVP, OSPF, IS-IS

None STP None None CP

mp2mp MPLS (tunnel)

mp2mp MPLS (PW)

mp2mp E-LAN (VPLS-like) mp2mp E-LAN (802.1ad) p2p E-line p2p PDH, STM p2p, mp2mp Client


P2P EVC over T-MPLS

(PE) (PE)(P)

Metro T-MPLS Network

This mapping is described in the approved version of G.8110.1


T-MPLS Data Plane & OAMInterworking at Ethernet level

1:1 1:1T-MPLS circuitT-MPLS circuit

Y.17tomT-MPLS circuit OAM

N:1 1:NT-MPLS path T-MPLS path T-MPLS path

T-MPLS path OAMY.17tom

MAC cVId, sVIdClient MAC cVId (sVId) MAC cVid, sVid

Client OAMY.1731 – IEEE 802.3

T-MPLSNetwork


Aggregation network(e.g. UTRAN)

BACKBONEPKT access network

PKT access network

Mobile Backhauling Application with T-MPLS

BS

FE

BSFE

Mobile Controller

Center

RNC

MSC

3G Node

B

N x E1 ATM/IMA

2G BTS

N x E1 TDM

BS

FE

3G Node

B2G BTS

N x E1 TDM

N x E1 ATM/IMA

Mobile backhauling applications typically require the coexistence of TDM (E1, T1) streams along

with L2 (ATM, Ethernet) streams on the same aggregation

network

Agnostic network with packet transport evolving

to T-MPLS

Migration towards T-MPLS allows for QoS, traffic

engineering, OAM, protection and statistical multiplexing under a common operation

paradigm with the other transport layers.

There are cases in which the access part is constrained to be “packet only”, e.g. due to the reuse of triple-play infra-

structure

CES is used to cross access packet based areas and is ideally terminated at the ingress of the agnostic network. (T)MPLS in the

access network would allow for (packet) e2e monitoring.

Debby Schryer

Can "Controller Center" be "Control Center"?


T-MPLSNetwork

T-MPLS Data Plane & OAMA possible interworking at pseudowire level (IETF – Y.17tom)

MPLS PW MPLS PWClient

Client OAMBFD (e2e)

1:1 1:1MPLS PW T-MPLS circuitT-MPLS circuit

T-MPLS circuit OAM …Y.17tom (Tandem Connection)

N:1 1:NMPLS tunnel MPLS tunnelT-MPLS path TMPLS path TMPLS path


Debby Schryer

Y.17tom is not an IETF designation. Sounds like ITU-T.


Network Model for IP Backbone: MPLS Routers

PE(P) PE(P)T-switch T-switch

DP: T-MPLSCP:GMPLS

OAM: T-MPLSProtection: T-MPLS/GMPLS

T-MPLS path with T-MPLS label swap

T-MPLS

MPLS tunnel with MPLS label swap

DP: MPLSCP: MPLS

OAM: MPLSProtection: MPLS

DP: MPLSCP: MPLS

OAM: MPLSProtection: MPLS

T-MPLS is an overlay network with respect to MPLS PE-P routers are aware of border T-switch only The interface between a border T-switch and a PE-P router is a MPLS

interface Two different MPLS/GMPLS interworking solutions can be defined,

“trusted” and “not trusted”


T-MPLSNetwork

T-MPLS Data Plane & OAMA possible interworking at MPLS tunnel level (IETF – Y.17tom)

MPLS tunnel MPLS tunnel MPLS tunnel MPLS tunnel

Client OAMBFD (e2e)

Client


N:1 1:NT-MPLS path T-MPLS path T-MPLS path

T-MPLS circuit OAM …Y.17tom (Tandem Connection)

T-MPLS circuit 1:1 1:1MPLS tunnel T-MPLS circuit

Debby Schryer

Y.17tom sounds like ITU-T


5 Conclusions


Conclusions

The Transport Network doesn’t change role over time Scalability, multiservice, quality, and lowest-cost-per-bit are invariable

requirements, always Transformation to “all-IP” service model calls for a comprehensive

Packet Transport Networking technology T-MPLS is carrier-grade, purpose-designed for Packet Transport

Networking Synthesis of excellence from the two worldwide authorities on

packets (IETF) and transport (ITU) MPLS-based, but transport-oriented (OAM-friendly) Client-independent, medium-independent (multiservice) Cost-effective (comprehensive operations, IP-free) Scalable, also in the control/management plane (GMPLS)

T-MPLS is an ideal choice for Packet Transport Networks.


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21407- Transport MPLS Rationale and Features Final v3 DS0110