Carrier Ethernet goes MPLS-TP - current · PDF filePure IP/MPLS is not optimized for transport networks T-MPLS does the job, but was terminated by ITU due to the founding of the Joint

T-Systems Berlin, 7.10.2008 - 20. Meeting ITG 5.2.3 (NGN) - TU Chemnitz - Th. M. Knoll

Carrier Ethernet goes MPLS-TP current observations

ITG-FG 5.2.3 - Next Generation Networks20. Sitzung am 07.10. 2008 – T-Systems

Thomas Martin KnollChemnitz University of TechnologyCommunication NetworksPhone 0371 531 33246Email [email protected]


Outline

1. Carrier Ethernet recall2. MPLS Traffic Profile (MPLS-TP)3. Observed trends & Summary

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Carrier Ethernet recall VLAN XCSynonyms: VLAN XC, VLAN Cross Connect, ELS

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Customer Edge C-tag (Customer VLAN tag - 8100)

DA

Bytes6

SA

6

T/L

2

DATA

46 .. 1500

FCS

4

PAD

2

TPI = 8100 VLAN TCI

2

C-tag

XC-tag

„tag exchange at the edge and tag swap at

each nodeDA

Bytes6

SA

6

T/L

2

DATA

46 .. 1500

FCS

4

PAD

2

TPI = 8100 VLAN TCI

2

XC-tag

DA

Bytes6

SA

6

T/L

2

DATA

46 .. 1500

FCS

4

PAD

2

TPI = 8100 VLAN TCI

22

TPI = 88A8 VLAN TCI

2„double tagged“ – EVXC (24bit)

Supported by: Siemens

CE recall MPLS-TP Trends/Summary


Carrier Ethernet recall Q-in-QSynonyms: Q-in-Q, PVT, stacked VLAN, Provider Bridges

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Provider Edge S-tag (Service VLAN tag – 88A8)

DA

Bytes6

SA

6

T/L

2

DATA

46 .. 1500

FCS

4

PAD

2

TPI = 8100 VLAN TCI

2

DA

Bytes6

SA

6

T/L

2

DATA

46 .. 1500

FCS

4

PAD

2

TPI = 8100 VLAN TCI

22

TPI = 88A8 VLAN TCI

2

C-tag

S-tag

„double tagged“

User PriorityPriority Code Point

Bits3

DEI

1

S-VIDService VLAN Identifier

12

3 bit PCP 8 classes 12 bit VID 4096 VLANs1 bit Drop Eligible Indicator drop first, if congestion occurs



Carrier Ethernet recall MAC-in-MACSynonyms: MAC-in-MAC, Provider Backbone Bridges (PBB)

5 / 21IEEE standard‘s page: http://www.ieee802.org/1/pages/802.1ah.html


Backbone Edge B-tag & I-tag (Instance VLAN tag – 88E7)

DA

Bytes6

SA

6

T/L

2

DATA

46 .. 1500

FCS

4

PAD

2

TPI = 8100 VLAN TCI

2

DA

Bytes6

SA

6

T/L

2

DATA

46 .. 1500

FCS

4

PAD

2

TPI = 88E7 I-Tag TCI

162

TPI = 88A8 VLAN TCI

2

C-tag

B-tag = S-tag

PCP

Bits3

I-SIDBackbone Service Instance Identifier

48

3 bit PCP 8 classes 24 bit I-SID 16777216 B-Services instances1 bit Drop Eligible Indicator

w / wo

„MAC encap.“

C-SAC-DA

4824

Res

2

Res

1

NC

A

1

DEI

1

1 bit No Customer Addresses

B-tag I-tag


http://www.ieee802.org/1/pages/802.1ah.html


Carrier Ethernet recall PBB-TE - 802.1QaySynonyms: PBB-TE / PBT - 802.1Qay

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Frame structure identical to 802.1ah

• point-to-point tunnel technologytunnel technology with transparent transport• 24 bit I-SID 224 provider service instances with unique LAN-ID• forwarding is based on B-DA und B-VID only 46 + 12 bit tunnels• L2 flooding and MAC learning is turned off !• loop prevention through tunnel design only no STP !• currently: Tunnel setup through SNMP• GMPLS Control of 802.1Qay Networks IEEE & IETF liasion• 802.1ag for CFM (connectivity fault management) using CCM (continuity

check messages)



T-MPLS recapITU-T’s approach

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[CE

_TU

TE]



MPLS Traffic Profile (MPLS-TP)Current shift from PBB-TE to MPLS-TP

Pure IP/MPLS is not optimized for transport networksT-MPLS does the job, but was terminated by ITU due to the founding of the Joint Working Team (JWT) together with IETFThe new drive of T-MPLS is called “MPLS-TP” and includes a shared work concept (IETF for all MPLS related parts and ITU for the transport specifics)Major reasons for the shifts:- PBB-TE standard is not ready and slowly progressing- PBB-TE control plane is not readily available- MPLS technology is mature, widely known and pushed by Cisco“ IETF sticks in the transport profile definition to the ITU requirements and ITU stops its work on T-MPLS”

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MPLS Traffic Profile (MPLS-TP)Current shift from PBB-TE to MPLS-TP NSN choice

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[CE

_TU

TE]



MPLS Traffic Profile (MPLS-TP)Current shift from PBB-TE to MPLS-TP NSN comparison

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[CE

_TU

TE]



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview

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[CE

_TU

TE]



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview

Current MPLS-TP documents:https://datatracker.ietf.org/idtracker/ ("mpls-tp" as filename search)draft-bryant-mpls-tp-jwt-report Status reportdraft-blb-mpls-tp-framework Optical OAM + MPLS networking frameworkdraft-bocci-pwe3-mpls-tp-ge-ach GEneric Associated Channel Header (GE-ACH) as control channeldraft-gray-mpls-tp-nm-req Network management requirementsdraft-jenkins-mpls-mpls-tp-requirements MPLS-TP requirementsdraft-sprecher-mpls-tp-oam-analysis MPLS-TP OAM analysisdraft-sprecher-mpls-tp-survive-fwk Restoration and resilience in MPLS-TPdraft-vigoureux-mpls-tp-gal “Generic-ACH Label (GAL)” assignment e.g. for OAM usagedraft-vigoureux-mpls-tp-oam-requirements OAM revival of ITU-T Supplement Y.Sup4

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https://datatracker.ietf.org/idtracker/

http://www.ietf.org/internet-drafts/draft-bryant-mpls-tp-jwt-report

http://www.ietf.org/internet-drafts/draft-blb-mpls-tp-framework

http://www.ietf.org/internet-drafts/draft-bocci-pwe3-mpls-tp-ge-ach

http://www.ietf.org/internet-drafts/draft-gray-mpls-tp-nm-req

http://www.ietf.org/internet-drafts/draft-jenkins-mpls-mpls-tp-requirements

http://www.ietf.org/internet-drafts/draft-sprecher-mpls-tp-oam-analysis

http://www.ietf.org/internet-drafts/draft-sprecher-mpls-tp-survive-fwk

http://www.ietf.org/internet-drafts/draft-vigoureux-mpls-tp-gal

http://www.ietf.org/internet-drafts/draft-vigoureux-mpls-tp-oam-requirements


MPLS Traffic Profile (MPLS-TP)MPLS-TP overview – likely IETF structure

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[JW

T]

Requirements(MPLS WG)

Transport Profile Architectural Framework(MPLS WG)

Alert Label Definition(MPLS WG)

ACH Definition(PWE3 WG)

Survivability(MPLS WG)

Control Plane(CCAMP WG)

Network Management(MPLS WG)



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview – Terminology

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[JW

T]

Multi-node PSN cloudPseudo-wire

PW1

Emulated Service

AttachmentCircuit

PE1 PE2CE1 CE2

AttachmentCircuit

Definition of an MPLS Transport Profile (TP) within IETF MPLS standardsBased on PWE3 and LSP forwarding architecture IETF MPLS architecture concepts

The major construct of the transport profile for MPLS are LSPsPW are a client layer



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview – Provisioning

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[JW

T]

Static through NMSestablishment of bi-directional LSPs (ensuring bi-directional congruency)

Dynamic using GMPLSbi-directional RSVP LSP setup within GMPLs framework



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview – ACH

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[JW

T]

Associated Channel Level (ACH) concpetGeneralised mechanism for carrying management / OAM information OAM capabilities : Connectivity Checks (CC) and “Connectivity Verification”(CV)Management information: Embedded Control Channel (ECC)To support the Data Communications Network (DCN) and the SignallingCommunication Network (SCN) – see G.7712APS information



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview – Monitoring and Alarm

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[JW

T]

LSP monitoring and alarming Generic Exception Label and Generic Associated Channel Proposal Specific Transport Alert Label (TAL) from reserved label space ( 13)Generic Associated Channel function within Generic Exception Label

MAC Header Channel payloadL1 L2 LFU/BoS Generic ACH

0001 | Ver | Resv | Channel Type



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview – Control plane

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[JW

T]

Provider BProvider A

Data Frames

A B C D E F

S-PES-PE T-PET-PE

CP CP CP CP CP CP

PW-Segment A

LSP-Tunnel A

PW-Segment B

LSP-Tunnel B

SCN GW

PW-Seg. AB

SCN-ASCN-A SCN-BSCN-B

RSVP-TE RSVP-TE

T-LDP

RSVP-TE

T-LDP

RSVP-TE

T-LDP

RSVP-TE

T-LDP

RSVP-TE

LSP-

Tunnel

AC E-NNI ACI-NNI I-NNI I-NNI I-NNI

AC – Attachment CircuitNNI – Network-Network InterfaceI-NNI – Internal NNIE-NNI – External NNISCN – Signaling Communication NetworkSCN-GW GatewayT-LDP – Targeted LDP

C1 C2

RSVP-TE

C(B)/0 C(C)/0 F(E)/0 F(F)/0F(C)p/1

CWF(C)p/1

CWF(F)p/1

CWF(F)p/1

CW

D(D)/0F(D)p/1

CW

LSP tunnel

MS-PW



MPLS Traffic Profile (MPLS-TP)MPLS-TP overview – further reading

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[JW

T]

“MPLS Architectural Considerations for a Transport Profile”


http://ties.itu.int/ftp/public/itu-t/ahtmpls/readandwrite/doc_exchange/overview/old/MPLS-TP_overview-03.pdf


Observed trends / SummaryCurrent

Carrier Ethernet standardisation is lowed downMPLS-TP will at least co-existProviders are likely to adopt to MPLS-TP since they already use MPLS in their networksITU’s transport contributions are adopted and remain almost unchangedon the other hand, ITU points out weaknesses in IETF drafts errata authorsWith Cisco’s support, Huaweis interest and NSN’s focus on MPLS-TP, the envisaged standardization by the end of 2009 is realistic.

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Sources[CE_TUTE] Gruber, C., Autenrieth, A., “Carrier Ethernet Transport in Metro and Core

Networks”, Conference tutorial, Networks 2008, September 2008[JWT] Ward, D., Betts, M., “MPLS Architectural Considerations for a Transport Profile”,

April 2008[WEBINAR] Howard, M., Malis, A.G., Dawood, S., “Understanding the New MPLS-TP”

Telecommunications Magazine, August 2008.

Documents

Carrier Ethernet goes MPLS-TP - current · PDF filePure IP/MPLS is not optimized for transport networks T-MPLS does the job, but was terminated by ITU due to the founding of the Joint