Internet DRAFT - draft-ietf-mpls-tp-use-cases-and-design
draft-ietf-mpls-tp-use-cases-and-design
INTERNET-DRAFT L. Fang, Ed.
Intended Status: Informational Cisco
Expires: November 1, 2013 N. Bitar
Verizon
R. Zhang
Alcatel Lucent
M. Daikoku
KDDI
P. Pan
Infinera
May 1, 2013
MPLS-TP Applicability; Use Cases and Design
draft-ietf-mpls-tp-use-cases-and-design-08.txt
Abstract
This document provides the applicability of Multiprotocol Label
Switching Transport Profile (MPLS-TP) with use case studies and
network design considerations. The use cases include Metro Ethernet
access and aggregation transport, Mobile backhaul, and packet optical
transport.
Status of this Memo
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provisions of BCP 78 and BCP 79.
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Copyright and License Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Background . . . . . . . . . . . . . . . . . . . . . . . . 4
2. MPLS-TP Use Cases . . . . . . . . . . . . . . . . . . . . . . . 6
2.1. Metro Access and Aggregation . . . . . . . . . . . . . . . 6
2.2. Packet Optical Transport . . . . . . . . . . . . . . . . . 7
2.3. Mobile Backhaul . . . . . . . . . . . . . . . . . . . . . . 7
2.3.1. 2G and 3G Mobile Backhaul . . . . . . . . . . . . . . . 8
2.3.2. 4G/LTE Mobile Backhaul . . . . . . . . . . . . . . . . 8
3. Network Design Considerations . . . . . . . . . . . . . . . . . 9
3.1. The role of MPLS-TP . . . . . . . . . . . . . . . . . . . . 9
3.2. Provisioning mode . . . . . . . . . . . . . . . . . . . . . 9
3.3. Standards compliance . . . . . . . . . . . . . . . . . . . 10
3.4. End-to-end MPLS OAM consistency . . . . . . . . . . . . . . 10
3.5. PW Design considerations in MPLS-TP networks . . . . . . . 11
3.6. Proactive and on-demand MPLS-TP OAM tools . . . . . . . . . 11
3.7. MPLS-TP and IP/MPLS Interworking considerations . . . . . . 12
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 12
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 12
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
7.1. Normative References . . . . . . . . . . . . . . . . . . . 13
7.2. Informative References . . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
Contributors' Addresses . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
This document provides applicability, use case studies and network
design considerations for the Multiprotocol Label Switching Transport
Profile (MPLS-TP).
1.1. Terminology
Term Definition
------ -------------------------------------------------------
2G 2nd generation wireless telephone technology
3G 3rd generation of mobile telecommunications technology
4G 4th Generation Mobile network
ADSL Asymmetric Digital Subscriber Line
AIS Alarm Indication Signal
ASNGW Access Service Network Gateway
ATM Asynchronous Transfer Mode
BFD Bidirectional Forwarding Detection
BTS Base Transceiver Station
CC-CV Continuity Check and Connectivity Verification
CDMA Code Division Multiple Access
E-LINE Ethernet point-to-point connectivity
E-LAN Ethernet LAN, provides multipoint connectivity
eNB Evolved Node B
EPC Evolved Packet Core
E-VLAN Ethernet Virtual Private LAN
EVDO Evolution-Data Optimized
G-ACh Generic Associated Channel
GAL G-ACh Label
GMPLS Generalized Multi-Protocol Label Switching
GSM Global System for Mobile Communications
HSPA High Speed Packet Access
IPTV Internet Protocol television
L2VPN Layer 2 Virtual Private Network
L3VPN Layer 3 Virtual Private Network
LAN Local Access Network
LDI Link Down Indication
LDP Label Distribution Protocol
LSP Label Switched Path
LTE Long Term Evolution
MEP Maintenance Entity Group End Point
MIP Maintenance Entity Group Intermediate Point
MPLS MultiProtocol Label Switching
MPLS-TP MultiProtocol Label Switching Transport Profile
MS-PW Multi-Segment Pseudowire
NMS Network Management System
OAM Operations, Administration, and Maintenance
OPEX Operating Expenses
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PE Provider-Edge device
PDN GW Packet Data Network Gateway
PW Pseudowire
RAN Radio Access Network
RDI Remote Defect Indication
S1 LTE Standardized interface between eNB and EPC
SDH Synchronous Digital Hierarchy
SGW Serving Gateway
SLA Service Level Agreement
SONET Synchronous Optical Network
S-PE PW Switching Provider Edge
SP Service Provider
SRLG Shared Risk Link Groups
SS-PW Single-Segment Pseudowire
TDM Time Division Multiplexing
TFS Time and Frequency Synchronization
tLDP Targeted Label Distribution Protocol
VPN Virtual Private Network
UMTS Universal Mobile Telecommunications System
X2 LTE Standardized interface between eNBs for handover
1.2. Background
Traditional transport technologies include SONET/SDH, TDM, and ATM.
There is a transition away from these transport technologies to new
packet transport technologies. In addition to the increasing demand
for bandwidth, packet transport technologies offer the following key
advantages:
Bandwidth efficiency: Traditional transport technologies support
fixed Bandwidth, no packet statistical multiplexing, the bandwidth is
reserved in the transport network regardless it is used by the client
or not. In contrast, packet technologies support statistical
multiplexing. This is the most important motivation for the
transition from traditional transport technologies to packet
transport technologies. The proliferation of new distributed
applications which communicate with servers over the network in a
bursty fashion has been driving the adoption of packet transport
techniques, since packet multiplexing of traffic from bursty sources
provides more efficient use of bandwidth than traditional circuit-
based TDM technologies.
Flexible data rate connections: The granularity of data rate
connections of traditional transport technologies is limited to the
rigid PDH or SONET hierarchy (e.g., DS1, DS3, OC3, OC12, etc.).
Packet technologies support flexible data rate connections. The
support of finer data rate granularity is particularly important for
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today's wireline and wireless services and applications.
QoS support: While traditional transport technology, such as TDM, has
very limited QoS support, packet transport can provide proper QoS
treatment for IPTV, Voice and Video over IP applications.
The root cause for transport moving to packet transport is the shift
of application from TDM to packet. For example, Voice TDM to VoIP;
Video to Video over IP; TDM access lines to Ethernet; TDM VPNs to IP
VPNs and Ethernet VPNs. In addition, network convergence and
technology refreshes demand for common and a flexible infrastructure
that provides multiple services.
As part of MPLS family, MPLS-TP complements existing IP/MPLS
technologies; it closes the gaps in the traditional access and
aggregation transport to enable end-to-end packet technology
solutions in a cost efficient, reliable, and interoperable manner.
After several years of industry debate on which packet technology to
use, MPLS-TP has emerged as the next generation transport technology
of choice for many Service Providers worldwide.
The Unified MPLS strategy - using MPLS from core to aggregation and
access (e.g. IP/MPLS in the core, IP/MPLS or MPLS-TP in aggregation
and access) appear to be very attractive to many SPs. It streamlines
the operation, reduces the overall complexity, and improves end-to-
end convergence. It leverages the MPLS experience, and enhances the
ability to support revenue generating services.
MPLS-TP is a subset of MPLS functions that meet the packet transport
requirements defined in [RFC5654]. This subset includes: MPLS data
forwarding, pseudo-wire encapsulation for circuit emulation, and
dynamic control plane using GMPLS control for LSP and tLDP for
pseudo-wire (PW). MPLS-TP also extends previous MPLS OAM functions,
such as BFD extension for proactive Connectivity Check and
Connectivity Verification (CC-CV) [RFC6428], and Remote Defect
Indication (RDI) [RFC6428], LSP Ping Extension for on-demand CC-CV
[RFC6426]. New tools have been defined for alarm suppression with
Alarm Indication Signal (AIS) [RFC6427], and switch-over triggering
with Link Defect Indication (LDI) [RFC6427]. Note that since the MPLS
OAM feature extensions defined through the process of MPLS-TP
development are part of the MPLS family, the applicability is general
to MPLS, and not limited to MPLS-TP.
The requirements of MPLS-TP are provided in MPLS-TP Requirements [RFC
5654], and the architectural framework is defined in MPLS-TP
Framework [RFC5921]. This document's intent is to provide the use
case studies and design considerations from a practical point of view
based on Service Providers deployments plan as well as actual
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deployments.
The most common use cases for MPLS-TP include Metro access and
aggregation, Mobile Backhaul, and Packet Optical Transport. MPLS-TP
data plane architecture, path protection mechanisms, and OAM
functionality are used to support these deployment scenarios.
The design considerations discussed in this document include: the
role of MPLS-TP in the network; provisioning options; standards
compliance; end-to-end forwarding and OAM consistency; compatibility
with existing IP/MPLS networks; and optimization vs. simplicity
design trade-offs.
2. MPLS-TP Use Cases
2.1. Metro Access and Aggregation
The use of MPLS-TP for Metro access and aggregation transport is the
most common deployment scenario observed in the field.
Some operators are building green-field access and aggregation
transport infrastructure, while others are upgrading/replacing their
existing transport infrastructure with new packet technologies. The
existing legacy access and aggregation networks are usually based on
TDM or ATM technologies. Some operators are replacing these networks
with MPLS-TP technologies, since legacy ATM/TDM aggregation and
access are becoming inadequate to support the rapid business growth
and too expensive to maintain. In addition, in many cases the legacy
devices are facing End of Sale and End of Life issues. As operators
must move forward with the next generation packet technology, the
adoption of MPLS-TP in access and aggregation becomes a natural
choice. The statistical multiplexing in MPLS-TP helps to achieve
higher efficiency compared with the time division scheme in the
legacy technologies. MPLS-TP OAM tools and protection mechanisms help
to maintain high reliability of transport networks and achieve fast
recovery.
As most Service Providers' core networks are MPLS enabled, extending
the MPLS technology to the aggregation and access transport networks
with a Unified MPLS strategy is very attractive to many Service
Providers. Unified MPLS strategy in this document means having end-
to-end MPLS technologies through core, aggregation, and access. It
reduces OPEX by streamlining operation and leveraging the operational
experience already gained with MPLS technologies; it also improves
network efficiency and reduces end-to-end convergence time.
The requirements from the SPs for ATM/TDM aggregation replacement
often include: i) maintaining the previous operational model, which
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means providing a similar user experience in NMS, ii) supporting the
existing access network, (e.g., Ethernet, ADSL, ATM, TDM, etc.), and
connections with the core networks, and iii) supporting the same
operational capabilities and services (L3VPN, L2VPN, E-LINE/E-LAN/E-
VLAN, Dedicated Line, etc.). MPLS-TP can meet these requirements and
in general the requirements defined in [RFC5654] to support a smooth
transition.
2.2. Packet Optical Transport
Many SP's transport networks consist of both packet and optical
portions. The transport operators are typically sensitive to network
deployment cost and operational simplicity. MPLS-TP supports both
static provisioning through NMS and dynamic provisioning via the
GMPLS control plane. As such, it is viewed as a natural fit in some
of the transport networks, where the operators can utilize the MPLS-
TP LSP's (including the ones statically provisioned) to manage user
traffic as "circuits" in both packet and optical networks, and when
they are ready, move to dynamic control plane for greater efficiency.
Among other attributes, bandwidth management, protection/recovery and
OAM are critical in Packet/Optical transport networks. In the context
of MPLS-TP, each LSP is expected to be associated with a fixed amount
of bandwidth in terms of bits-per-second and/or time-slots. OAM is to
be performed on each individual LSP. For some of the performance
monitoring (PM) functions, the OAM mechanisms need to be able to
transmit and process OAM packets at very high frequency. An overview
of MPLS-TP OAM toolset is found in [RFC6669].
Protection [RFC6372] is another important element in transport
networks. Typically, ring and linear protection can be readily
applied in metro networks. However, as long-haul networks are
sensitive to bandwidth cost and tend to have mesh-like topology,
shared mesh protection is becoming increasingly important.
In some cases, SPs plan to deploy MPLS-TP from their long haul
optical packet transport all the way to the aggregation and access in
their networks.
2.3. Mobile Backhaul
Wireless communication is one of the fastest growing areas in
communication worldwide. In some regions, the tremendous mobile
growth is fueled by the lack of existing land-line and cable
infrastructure. In other regions, the introduction of smart phones is
quickly driving mobile data traffic to become the primary mobile
bandwidth consumer (some SPs have already observed more than 85% of
total mobile traffic are data traffic). MPLS-TP is viewed as a
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suitable technology for Mobile backhaul.
2.3.1. 2G and 3G Mobile Backhaul
MPLS-TP is commonly viewed as a very good fit for 2G/3G mobile
backhaul. 2G (GSM/CDMA) and 3G (UMTS/HSPA/1xEVDO) Mobile Backhaul
Networks are still currently dominating the mobile infrastructure.
The connectivity for 2G/3G networks is point to point (P2P). The
logical connections are hub-and-spoke. Networks are physically
constructed using a star or ring topology. In the Radio Access
Network (RAN), each mobile Base Transceiver Station (BTS/Node B) is
communicating with a Radio Controller (BSC/RNC). These connections
are often statically set up.
Hierarchical or centralized architectures are often used for pre-
aggregation and aggregation layers. Each aggregation network inter-
connects with multiple access networks. For example, a single
aggregation ring could aggregate traffic for 10 access rings with a
total of 100 base stations.
The technology used today is largely ATM based. Mobile providers are
replacing the ATM RAN infrastructure with newer packet technologies.
IP RAN networks with IP/MPLS technologies are deployed today by many
SPs with great success. MPLS-TP is another suitable choice for Mobile
RAN. The P2P connections from base station to Radio Controller can be
set statically to mimic the operation of today's RAN environments;
in-band OAM and deterministic path protection can support fast
failure detection and switch-over to satisfy the SLA agreements.
Bidirectional LSPs may help to simplify the provisioning process. The
deterministic nature of MPLS-TP LSP set up can also support packet
based synchronization to maintain predictable performance regarding
packet delay and jitters. The traffic engineered and co-routed
bidirectional properties of an MPLS-TP LSP are of benefit in
transporting packet based Time and Frequency Synchronization (TFS)
protocols such as [1588overmpls]. However, the choice between an
external, physical layer or packet based TFS method is network
dependent and thus is out of scope of this document.
2.3.2. 4G/LTE Mobile Backhaul
One key difference between LTE and 2G/3G mobile networks is that the
logical connection in LTE is a mesh, while in 2G/3G is a P2P star. In
LTE, the base stations eNB/BTS communicate with multiple Network
controllers (PDN GW/SGW or ASNGW), and the radio elements communicate
with one another for signal exchange and traffic offload to wireless
or wireline infrastructures.
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IP/MPLS has a great advantage in any-to-any connectivity
environments. Thus, the use of mature IP or L3VPN technologies is
particularly common in the design of SP's LTE deployment plans.
The extended OAM functions defined in MPLS-TP, such as in-band OAM
and path protection mechanisms bring additional advantages to support
SLAs. The dynamic control-plane with GMPLS signaling is especially
suited for the mesh environment, to support dynamic topology changes
and network optimization.
Some operators are using the same model as in 2G and 3G Mobile
Backhaul, which uses IP/MPLS in the core, and MPLS-TP with static
provisioning (through NMS) in aggregation and access. The reasoning
is as follows: the X2 traffic load in LTE networks currently may be a
very small percentage of the total traffic. For example, one large
mobile operator observed that X2 traffic was less than one percent of
the total S1 traffic. Therefore, optimizing the X2 traffic may not be
the design objective in this case. The X2 traffic can be carried
through the same static tunnels together with the S1 traffic in the
aggregation and access networks, and further forwarded across the
IP/MPLS core. In addition, mesh protection may be more efficient with
regard to bandwidth utilization, but linear protection and ring
protection are often considered simpler by some operators from the
point of view of operation maintenance and trouble shooting, and so
are widely deployed. In general, using MPLS-TP with static
provisioning for LTE backhaul is a viable option. The design
objective of using this approach is to keep the operation simple and
use a common model for mobile backhaul, especially during the
transition period.
The TFS considerations stated in Section 3.3.1 apply to the 4G/LTE
Mobile Backhaul case as well.
3. Network Design Considerations
3.1. The role of MPLS-TP
The role of MPLS-TP is to provide a solution to help evolve
traditional transport towards packet. It is designed to support the
transport characteristics/behavior described in [RFC5654]. The
primary use of MPLS-TP is largely to replace legacy transport
technologies, such as SONET/SDH. MPLS-TP is not designed to replace
the service support capabilities of IP/MPLS, such as L2VPN, L3VPN,
IPTV, Mobile RAN, etc.
3.2. Provisioning mode
MPLS-TP supports two provisioning modes: i) a mandatory static
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provisioning mode, which must be supported without dependency on
dynamic routing or signaling; and ii) an optional distributed dynamic
control plane, which is used to enable dynamic service provisioning.
The decision on which mode to use is largely dependent on the
operational feasibility and the stage of network transition.
Operators who are accustomed to the transport-centric operational
model (e.g., NMS configuration without control plane) typically
prefer the static provisioning mode. This is the most common choice
in current deployments. The dynamic provisioning mode can be more
powerful but it is more suited to operators who are familiar with the
operation and maintenance of IP/MPLS technologies or are ready to
step up through training and planned transition.
There may be also cases where operators choose to use the combination
of both modes. This is appropriate when parts of the network are
provisioned in a static fashion and other parts are controlled by
dynamic signaling. This combination may also be used to transition
from static provisioning to dynamic control plane.
3.3. Standards compliance
It is generally recognized by SPs that standards compliance is
important for lowering cost, accelerating product maturity, achieving
multi-vendor interoperability, and meeting the expectations of their
enterprise customers.
MPLS-TP is a joint work between IETF and ITU-T. In April 2008, IETF
and ITU-T jointly agreed to terminate T-MPLS and progress MPLS-TP as
joint work [RFC5317]. The transport requirements are provided by ITU-
T, the protocols are developed in IETF.
3.4. End-to-end MPLS OAM consistency
End-to-end MPLS OAM consistency is highly desirable in order to
enable Service Providers to deploy an end-to-end MPLS solution. As
MPLS-TP adds OAM function to the MPLS toolkit, it cannot be expected
that a full-function end-to-end LSP with MPLS-TP OAM can be achieved
when the LSP traverses a legacy MPLS/IP core. Although it may be
possible to select a subset of MPLS-TP OAM that can be gatewayed to
the legacy MPLS/IP OAM, a better solution is achieved by tunneling
the MPLS-TP LSP over the legacy MPLS/IP network. In that mode of
operation, legacy OAM may be run on the tunnel in the core, and the
tunnel end-points may report issues in as much detail as possible to
the MIPs in the MPLS-TP LSP. Note that over time it is expected that
routers in the MPLS/IP core will be upgraded to fully support MPLS-TP
features: once this has occurred, it will be possible to run end-to-
end MPLS-TP LSPs seamlessly across the core.
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3.5. PW Design considerations in MPLS-TP networks
In general, PWs in MPLS-TP work the same as in IP/MPLS networks. Both
Single-Segment PW (SS-PW) and Multi-Segment PW (MS-PW) are supported.
For dynamic control plane, Targeted LDP (tLDP) is used. In static
provisioning mode, PW status is a new PW OAM feature for failure
notification. In addition, both directions of a PW must be bound to
the same transport bidirectional LSP.
In the common network topology involving multi-tier rings, the design
choice is between using SS-PW or MS-PW. This is not a discussion
unique to MPLS-TP, as it applies to PW design in general, but it is
relevant here, since MPLS-TP is more sensitive to the operational
complexities, as noted by operators. If MS-PW is used, Switched PE
(S-PE) must be deployed to connect the rings. The advantage of this
choice is that it provides domain isolation, which in turn
facilitates trouble shooting and allows for faster PW failure
recovery. On the other hand, the disadvantage of using S-PE is that
it adds more complexity. Using SS-PW is simpler, since it does not
require S-PEs, but less efficient because the paths across primary
and secondary rings are longer. If operational simplicity is a higher
priority, some SPs choose the latter.
Another design trade-off is whether to use PW protection in addition
to LSP protection or rely solely on LSP protection. When the MPLS-TP
LSPs are protected, if the working LSP fails, the protect LSP assures
that the connectivity is maintained and the PW is not impacted.
However, in the case of simultaneous failure of both working and
protect LSPs, the attached PW would fail. By adding PW protection,
and attaching the protect PW to a diverse LSP not in the same Shared
Risk Link Group (SRLG), the PW is protected even when the primary PW
fails. Clearly, using PW protection adds considerably more
complexity and resource usage, and thus operators often may choose
not to use it, and consider protection against single point of
failure as sufficient.
3.6. Proactive and on-demand MPLS-TP OAM tools
MPLS-TP provide both proactive and on-demand OAM Tools. As a
proactive OAM fault management tool, BFD Connectivity Check (CC) can
be sent at regular intervals for Connectivity Check; three missed CC
messages (or a configurable number) can trigger the failure
protection switch-over. BFD sessions are configured for both working
and protecting LSPs.
A design decision is choosing the value of the BFD CC interval. The
shorter the interval, the faster the detection time is, but also the
higher the resource utilization is. The proper value depends on the
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application and the service needs.
As an on-demand OAM fault management mechanism, for example when
there is a fiber cut, Link Down Indication (LDI) message [RFC6427]
can be generated from the failure point and propagated to the
Maintenance Entity Group End Points (MEPs) to trigger immediate
switch-over from working to protect path. An Alarm Indication Signal
(AIS) can be propagated from the Maintenance Entity Group
Intermediate Point (MIP) to the MEPs for alarm suppression.
In general, both proactive and on-demand OAM tools should be enabled
to guarantee short switch-over times.
3.7. MPLS-TP and IP/MPLS Interworking considerations
Since IP/MPLS is largely deployed in most SPs' networks, MPLS-TP and
IP/MPLS Interworking is inevitable if not a reality. However,
Interworking discussion is out of the scope of this document; it is
for further study.
4. Security Considerations
Under the use case of Metro access and aggregation, in the scenario
where some of the access equipment is placed in facilities not owned
by the SP, the static provisioning mode of MPLS-TP is often preferred
over the control plane option because it eliminates the possibility
of a control plane attack which may potentially impact the whole
network. This scenario falls into the Security Reference Model 2 as
described in [RFC6941].
Similar location issues apply to the mobile use cases, since
equipment is often placed in remote and outdoor environment, which
can increase the risk of un-authorized access to the equipment.
In general, NMS access can be a common point of attack in all MPLS-TP
use cases, and attacks to GAL or G-ACh are unique security treats to
MPLS-TP. The MPLS-TP security considerations are discussed in MPLS-TP
Security Framework [RFC6941]. General security considerations for
MPLS and GMPLS networks are addressed in Security Framework for MPLS
and GMPLS Networks [RFC5920].
5. IANA Considerations
This document contains no new IANA considerations.
6. Acknowledgements
The authors wish to thank Adrian Farrel for his review as Routing
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Area Director, Adrian's detailed comments and suggestions were of
great help for improving the quality of this document, and thank Loa
Andersson and Adrian Farrel for their continued support and guidance.
The authors would also like to thank Weiqiang Cheng for his helpful
input on LTE Mobile backhaul based on his knowledge and experience in
real world deployment, thank Stewart Bryant for his text contribution
on timing, thank Russ Housley for his improvement suggestions, thank
Andrew Malis for his support and use case discussion, thank Pablo
Frank, Lucy Yong, Huub van Helvoort, Tom Petch, Curtis Villamizar,
and Paul Doolan for their comments and suggestions, thank Joseph Yee
and Miguel Garcia for their APPSDIR and Gen-ART reviews and comments
respectively.
7. References
7.1. Normative References
[RFC5654] Niven-Jenkins, B., Ed., Brungard, D., Ed., Betts, M., Ed.,
Sprecher, N., and S. Ueno, "Requirements of an MPLS
Transport Profile", RFC 5654, September 2009.
[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, July 2010.
[RFC5921] Bocci, M., Ed., Bryant, S., Ed., Frost, D., Ed., Levrau,
L., and L. Berger, "A Framework for MPLS in Transport
Networks", RFC 5921, July 2010.
[RFC6426] Gray, E., Bahadur, N., Boutros, S., and R. Aggarwal, "MPLS
On-Demand Connectivity Verification and Route Tracing",
RFC 6426, November 2011.
[RFC6427] Swallow, G., Ed., Fulignoli, A., Ed., Vigoureux, M., Ed.,
Boutros, S., and D. Ward, "MPLS Fault Management
Operations, Administration, and Maintenance (OAM)",
RFC 6427, November 2011.
[RFC6428] Allan, D., Ed., Swallow Ed., G., and J. Drake Ed.,
"Proactive Connectivity Verification, Continuity Check,
and Remote Defect Indication for the MPLS Transport
Profile", RFC 6428, November 2011.
7.2. Informative References
[RFC5317] Bryant, S., Ed., and L. Andersson, Ed., "Joint Working
Team (JWT) Report on MPLS Architectural Considerations for
a Transport Profile", RFC 5317, February 2009.
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INTERNET DRAFT MPLS-TP Use Cases and Design May 1, 2013
[RFC6372] Sprecher, N., Ed., and A. Farrel, Ed., "MPLS Transport
Profile (MPLS-TP) Survivability Framework", RFC 6372,
September 2011.
[RFC6669] Sprecher, N. and L. Fang, "An Overview of the Operations,
Administration, and Maintenance (OAM) Toolset for MPLS-
Based Transport Networks", RFC 6669, July 2012.
[RFC6941] Fang, L. Ed., Niven-Jenkins, B., Ed., Mansfield,
S., Ed., and R. Graveman, Ed., "MPLS-TP Security
Framework," RFC 6941, April 2013.
[1588overmpls], Davari, S., Oren, A., Bhatia, M., Roberts, P., and
L. Montini, "Transporting Timing messages over MPLS
Networks," draft-ietf-tictoc-1588overmpls-04.txt, February
2013.
Authors' Addresses
Luyuan Fang
Cisco Systems, Inc.
111 Wood Ave. South
Iselin, NJ 08830
United States
Email: lufang@cisco.com
Nabil Bitar
Verizon
40 Sylvan Road
Waltham, MA 02145
United States
Email: nabil.bitar@verizon.com
Raymond Zhang
Alcatel-Lucent
701 Middlefield Road
Mountain View, CA 94043
United States
Email: raymond.zhang@alcatel-lucent.com
Masahiro Daikoku
KDDI corporation
3-11-11.Iidabashi, Chiyodaku, Tokyo
Japan
Email: ms-daikoku@kddi.com
Ping Pan
Infinera
Fang et al. Expires November 1, 2013 [Page 14]
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United States
Email: ppan@infinera.com
Contributors' Addresses
Kam Lee Yap
XO Communications
13865 Sunrise Valley Drive,
Herndon, VA 20171
United States
Email: klyap@xo.com
Dan Frost
Cisco Systems, Inc.
United Kingdom
Email:danfrost@cisco.com
Henry Yu
TW Telecom
10475 Park Meadow Dr.
Littleton, CO 80124
United States
Email: henry.yu@twtelecom.com
Jian Ping Zhang
China Telecom, Shanghai
Room 3402, 211 Shi Ji Da Dao
Pu Dong District, Shanghai
China
Email: zhangjp@shtel.com.cn
Lei Wang
Lime Networks
Strandveien 30, 1366 Lysaker
Norway
Email: lei.wang@limenetworks.no
Mach(Guoyi) Chen
Huawei Technologies Co., Ltd.
No. 3 Xinxi Road
Shangdi Information Industry Base
Hai-Dian District, Beijing 100085
China
Email: mach@huawei.com
Nurit Sprecher
Nokia Siemens Networks
3 Hanagar St. Neve Ne'eman B
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Hod Hasharon, 45241
Israel
Email: nurit.sprecher@nsn.com
Fang et al. Expires November 1, 2013 [Page 16]
