1. Evolving Transport
to Packet with
MPLS-TP
Luyuan Fang, Cisco Systems
Nabil Bitar, Verizon
Raymond Zhang, BT
FutureNet 2010
May 12, 2010, Boston
2. Agenda
Transport Moving toward Packet
Drivers and Requirements
MPLS-TP Technologies Overview
MPLS-TP Use Case Scenarios
Design Considerations
Standards Development Status
Conclusions
2
4. Transport Evolution – Moving Toward Packets
Drivers for moving from SONET/SDH TDM technologies to
packet switching
– Fast growing bandwidth demand - driven by new packet
applications/services
• IP Video: content downloading/streaming/sharing
• Mobile data: e.g. smart phone applications
• Triple play
• IP and Ethernet VPNS
– Network convergence and Technology refreshes
• Consolidate networks onto common infrastructure
• Replace aging legacy networks
Transport moving from SONET/SDH TDM toward packet transport
– Flexible data rates and statistical Multiplexing gains
– Lower cost
4
5. Service Providers Transport Requirements
Packet transport technology
– Reliable and stable
– Enables statistical multiplexing
– Flexible data rates
– High bandwidth
– Lower cost of ownership
Maintain current transport characteristics
– Client-Server relationship: Transport domain is independent of client
networks
– Forwarding Paradigm: Connection-oriented
– Transport OAM: In-band OAM
– Resiliency: Fast detection and recovery time without c/p (<50ms)
– Connection path determination and placement via
1) Network Management System (NMS)
2) Dynamic Control Plane
– Tight SLAs: BW and QoS guarantees, and high availability
5
6. Why MPLS-TP for Packet Transport?
MPLS-Transport Profile (MPLS-TP) is aimed to address
the NGN transport needs of high bandwidth packet
switched networks and satisfy carriers’ requirements
MPLS-TP provides in-band OAM, NMS-based
provisioning and maintenance, control plane, deterministic
path protection with fast recovery time, and lower total
cost of ownership
Leverages Service providers’ experience with MPLS
Standardization: Joint work by IETF and ITU-T.
– MPLS-TP protocols are developed in IETF
• Existing MPLS data plane (no IP user plane)
• Subset of MPLS, Pseudowire and GMPLS that satisfies
transport needs and requirements
• Extensions when needed ala OAM
– Leverage the expertise in IETF and insure interoperability
between MPLS-TP and existing MPLS technologies
6
8. IP And Transport Converging Under MPLS
MPLS-TP PW IP/MPLS
MPLS-TP OAM PHP
Path Protection MPLS Forwarding ECMP
50ms Switchover MPLS Forwarding MP2MP
Alarm and monitoring IP
Static Provisioning GMPLS
Transport MPLS IP
8 8
9. MPLS-TP Concept
NMS for Network
*Can use dynamic control
Management Control * plane
Working LSP
Client node PE PE Client node
Protect LSP
MPLS-TP LSP (Static or Dynamic)
Pseudowire E2e and
Section segment OAM
Section
Client Signal
Connection Oriented, pre-configured working path and protect path
Transport Tunnel 1:1 protection, switching triggered by in-band OAM
Phase 1: NMS for static provisioning
9
10. What is MPLS-TP?
Data Plane Control Plane
– MPLS Forwarding – NMS provisioning option
– Bidirectional P2P and P2MP LSPs – GMPLS control plane option
– No LSP merging – PW control plane option
– PHP optional
– PW (SS-PW, MS-PW)
OAM Resilency
– In-band OAM channel (GACH) – Sub-50ms protection switch over
– Connectivity Check (CC): proactive (ext. BFD) without c/p
– Connectivity verification (CV): reactive (ext. LSP – 1:1, 1+1, 1:N path protection
Ping) – Linear protection
– Alarm Suppression and Fault Indication with AIS – Ring protection
(new tool), RDI (ext. BFD), and Client Fault Indication
(CFI)
– Performance monitoring, proactive and reactive
(new tools)
10
11. MPLS-TP Architecture
Emulated Service
Pseudowire
Native Service Native Service
(Attachment (Attachment
Circuit) Circuit)
PW.Seg t1 PW.Seg t3
CE1 T-PE1 S-PE1
PW1 T-PE2 CE2
PW.Seg t2 PW.Seg t4
TP-LSP TP-LSP
PW.Seg t1 PW.Seg t3
PW.Seg t2 PW.Seg t4
TP-LSP TP-LSP
Basic construct of MPLS-TP:
–MPLS LSPs for transportation (LSPs can be nested)
–PWs for the client layer (SS-PW and MS-PW)
–All other types of traffic are carried by PW as client layer
11
12. MPLS-TP NGN Packet Transport
MPLS PWs (SS-PWs and MS-PWs): Provide circuit emulation for
native L2 connections over an MPLS PSN
LSPs: Provide for creating MPLS tunnels over an MPLS PSN that
can carry PWs or other LSPs (nesting)
Traffic-engineering capability (bandwidth guarantees)
Rich and mature traffic protection mechanisms
Rich control plane
Routing: OSPF-TE/ISIS-TE
Signaling: RSVP-TE with GMPLS extensions
Provide for very flexible hierarchical tunneling better scale in
core
Further enhancements are in progress in IETF/ITU joint effort
targeting OAM and protection schema
data-plane fault detection and notification
performance measurement
no dependence on IP data plane
12
14. MPLS-TP Potential Deployment
Scenarios
IP/MPLS and MPLS-TP Access and Aggregation Use
Cases
Replacing TDM SONET/ATM network with MPLS-TP
Mobile Backhaul
Carrier Ethernet Aggregation
Multi-service Support Transport
14
15. MPLS-TP in Aggregation and Access
AAA DHCP,DN EMS NMS Service and Performance Mgmt
Portal S
OAM Subsystem
)
Business
Edge Multiservice Core
oA
Access Aggregation
(C
Corporat
US
e
DI
RA
Residential Aggregation Node Distribution Node
VoD TV SIP
Ethernet
STB
BNG Content Network
2G/3G
MPLS-TP MPLS-TP IP/MPLS
Business
Node
e
Corporat
Aggregation Network Core Core Network
Residential
DSL
Business PE
STB
Business PON
Corporat
e
Residential Dark Fibre / CWDM / DWDM and ROADM
STB
Static or dynamic Static or Dynamic MPLS-TP
MPLS-TP IP/MPLS
15
16. Deployment Scenario 1:
Service Networks and MPLS-TP over OTN/DWDM
Ethernet Services
Attachment circuit (AC), LSP, or PW segment Network Island 3
PW, PW segment, or LSP
MPLS transport (MPLS, MPLS-TP) LSP tunnel
DWDM
Ethernet Ethernet
Service Networs Services Network
Island 1 Island 2
MPLS-TP IP MPLS Network
IP MPLS Network Domain Island 2
Island 1
UNI UNI
Client Network Transport Server Network Client Network
(e.g. Metro/Medium Haul. Long Haul)
• MPLS-TP provides transport services (server) for many client networks
•Ethernet services (native and Ethernet/MPLS) network: Inter-switch/router links, Ethernet tunnels transport
•IP MPLS services network : Inter-outer IP links transport
•Enterprises: Leased line replacement. Wireless backhaul is a special case
• Islands of a client services network form a contiguous domain (e.g., IGP domain)
•Client-transport network interface is a UNI
16
17. Deployment Scenario 2:
MPLS-TP for Carrier Ethernet Aggregation/Access
AAA DHCP,DN EMS NMS Service and Performance Mgmt
Portal S
OAM Subsystem
)
Business
Edge Multiservice Core
oA
Access Aggregation
(C
Corporat
US
e
DI
Aggregation Distribution
RA
Residential Node Node
VoD TV SIP
Ethernet
STB
BNG Content Network
2G/3G
MPLS-TP MPLS-TP IP/MPLS
Business
Node
e
Corporat
Aggregation Network Core Core Network
Residential
DSL
Business PE
STB
Business PON
Corporat
e
Residential
Static or dynamic
MPLS-TP Static or Dynamic MPLS IP/MPLS
STB
17
18. Deployment Scenario 3:
MPLS-TP for Mobile Backhaul
IP/ATM/TDM
Node B
BSC /
RNC
MPLS-TP Circuit Network
BTS
IP/MPLS Core
eNB Mobile Backhaul
S- GW / P-GW MME
Node B IP
Using PW in MPLS-TP to support legacy TDM, ATM and IP transport
Deterministic path provisioning
Protection with fast restoration
Backhaul performance monitoring
Interoperability with IP/MPLS and in RAN
Support 2G/3G/4G services
18
19. Deployment Scenario 4:
Backhaul with MPLS-TP MS-PW for Security Consideration
Existing Ethernet Existing Ethernet Provider Managed CPE
Provider
access termination access termination
Managed CPE
point point
Dynamically signaled LSP &
Statically or signaled Statically or signaled
PW labels
configured LSP & PW labels configured LSP & PW labels
(LDP & T-LDP)
BS
E1
BS
E1 PW Core PW E1 PW chSTM1
IM A/E1 ATM PW Core PW ATM PW
STM1*
BS Ethernet PW Core PW Ethernet PW
Transport VLAN Ethernet
Transport VLAN
(Etherway) (Etherway)
Ethernet
PW segment over Ethernet Same as Ethernet services PW segment over Ethernet
access VLAN(s) today access VLAN(s)
Key:
Transport
UNI/presentation
OSS/Static
Control plane signaled
Synchronization & Timing
OAM
*Could also be chSTM1 based on MOLO requirements
19
21. IETF/ITU-T Consensus
History
– “For a number of years, the ITU-T has been designing a connection-
oriented packet switched technology to be used in Transport Networks.”
[RFC5317]1
– Issues: Breaking the MPLS Forwarding paradigm, Jeopardizing the
value and functionality of the large-scale of deployed MPLS networks
and associated equipment
–“Development of T-MPLS was abandoned [RFC5317]1 by ITU-T Study
Group 15 due to inherent conflicts with the IETF MPLS design and, in
particular, with the Internet architecture. These conflicts arose due to the
lack of coordination with the IETF as the design authority for MPLS.”
[RFC 5704]2
T-MPLS is not MPLS-TP
IETF/ITU-T Consensus - Joint Work on MPLS-TP
- ITU-T provide transport requirements
- IETF develop protocol definitions
- Joint review of documents/specifications
1: [RFC 5317]: Joint Working Team (JWT) Report on MPLS Architectural Considerations for a Transport Profile, Feb. 2009.
2: [RFC 5704]: Uncoordinated Protocol Development Considered Harmful, Nov. 2009.
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22. IETF Development Status
IETF RFCs published
RFC 5317: JWT Report on MPLS Architectural Considerations for a Transport Profile
RFC 5586: MPLS Generic Associated Channel
RFC 5654: MPLS-TP Requirements
RFC 5704: Uncoordinated Protocol Development Considered Harmful
RFC 5718: An In-Band Data Communication Network For the MPLS Transport Profile
WG drafts
draft-ietf-mpls-tp-framework-07.txt
draft-ietf-mpls-tp-nm-req-06.txt
draft-ietf-mpls-tp-oam-framework-04.txt
draft-ietf-mpls-tp-survive-fwk-03.txt
draft-ietf-mpls-tp-nm-framework-04.txt
draft-ietf-mpls-tp-rosetta-stone-01
draft-ietf-mpls-tp-process-04.txt
draft-ietf-mpls-tp-oam-analysis-00.txt
draft-ietf-mpls-tp-identifiers-00.txt
Open issued under work
OAM: FM and PM related: involves BFD ext., certain aspect of Y.1731, MEP, MIP…
Protection: especially Ring Protection – proposal convergence in progress
22
23. MPLS-TP IETF Status
IETF RFCs published
RFC 5317: JWT Report on MPLS Architectural Considerations for a Transport Profile
RFC 5586: MPLS Generic Associated Channel
RFC 5654: MPLS-TP Requirements
RFC 5704: Uncoordinated Protocol Development Considered Harmful
RFC 5718: An In-Band Data Communication Network For the MPLS Transport Profile
The following is the latest update by MPLS WG at IETF 77, 3/25/2010:
WG Drafts (target date June 2010)
draft-ietf-mpls-tp-identifiers
draft-ietf-mpls-tp-framework
draft-ietf-mpls-tp-ach-tlv
draft-ietf-mpls-tp-data-plane
draft-ietf-mpls-tp-oam-framework
draft-ietf-mpls-tp-survive-fwk
In other working groups
draft-ietf-mpls-tp-control-plane-framework
draft-ietf-opsawg-mpls-tp-oam-def
23
24. Draft targeted for Feb 2011
- IETF update by MPLS WG at IETF 77, 3/25/2010
WG Drafts
draft-ietf-mpls-tp-fault
draft-ietf-mpls-tp-oam-analysis
draft-ietf-mpls-tp-linear-protection
Other working groups
draft-ietf-ccamp-rsvp-te-mpls-tp-oam-ext
draft-ietf-ccamp-oam-configuration-fwk
24
25. Draft targeted for Feb 2011 – II
- IETF update by MPLS WG at IETF 77, 3/25/2010
Individual Drafts
draft-asm-mpls-tp-bfd-cc-cv
draft-zhang-mpls-tp-pw-oam-config
draft-frost-mpls-tp-loss-delay
draft-zhl-mpls-tp-sd
draft-fang-mpls-tp-security-framework
draft-nitinb-mpls-tp-lsp-ping-bfd-procedures
draft-nitinb-mpls-tp-lsp-ping-extensions
draft-dai-mpls-tp-lock-instruct
draft-boutros-mpls-tp-loopback
draft-he-mpls-tp-csf
draft-flh-mpls-tp-oam-diagnostic-test
draft-fbb-mpls-tp-p2mp-framework
25
26. General Design Considerations
MPLS-TP vs. IP/MPLS
Operational experience
Transport requirements
Standards compliance
IETF standards are evolving, good progress
T-MPLS is not MPLS-TP - it would not inter-op with MPLS
Interoperability with IP/MPLS
MS PW support static to dynamic PW interconnect
End-to-end OAM – we are not there yet.
Resilency – fast switch over
sub 50ms switch over for liner and ring topology
Event driven with AIS/LDI
Scalability
Number of LSPs and PWs supported
BFD HW support
Performance monitoring
Delay / loss measurement
26
27. General Design Considerations
MPLS-TP vs. IP/MPLS
Operation experience
Transport requirements
Standards compliance
IETF standards are evolving, good progress
T-MPLS is not MPLS-TP
Interoperability with IP/MPLS
MS PW support static to dynamic PW interconnect
End-to-end OAM
Resilency – fast switch over
Scalability
27
28. Conclusions
Transport Evolution – toward Packet Transport
New services driving BW growth
Support IP, Ethernet, High BW, Statistical Multiplexing, low cost packet
transport
Moving away from SONET/SDH/ATM TDM technology to packet
MPLS-TP satisfies transport requirements, key characteristics
and needed interoperability with IP/MPLS
Common with IP/MPLS/GMPLS: Forwarding, PW, GMPLS
Enhanced OAM, Resiliency, Fast-switch over, NMS support
Provide a path for IP and transport to converge over MPLS umbrella
MPLS-TP Potential Use Case Examples
Metro Ethernet aggregation and access
Multi-service transport
Mobile backhaul
T-MPLS is not MPLS-TP
IETF and ITU-U consensus to terminate T-MPLS
IETF and ITU-T JWT joint effort developing MPLS-TP
28
