In telecommunications, Multiprotocol Label Switching - Transport Profile (MPLS-TP) is a variant of the MPLS protocol that is used in packet switched data networks. MPLS-TP is the product of a joint Internet Engineering Task Force (IETF) / International Telecommunication Union Telecommunication Standardization Sector (ITU-T) effort to include an MPLS Transport Profile within the IETF MPLS and PWE3 architectures to support the capabilities and functionalities of a packet transport network.
MPLS-TP is designed for use as a network layer technology in transport networks. It will be a continuation of the work started by the transport network experts of the ITU-T, specifically SG15, as T-MPLS. Since 2008 the work is progressed in a cooperation between ITU-T and IETF. The required protocol extensions to MPLS being designed by the IETF based on requirements provided by service providers. It will be a connection-oriented packet-switched (CO-PS) application. It will offer a dedicated MPLS implementation by removing features that are not relevant to CO-PS applications and adding mechanisms that provide support of critical transport functionality.
MPLS-TP is to be based on the same architectural principles of layered networking that are used in longstanding transport network technologies like SDH, SONET and OTN. Service providers have already developed management processes and work procedures based on these principles.
MPLS-TP gives service providers a reliable packet-based technology that is based upon circuit-based transport networking, and thus is expected to align with current organizational processes and large-scale work procedures similar to other packet transport technologies.
MPLS-TP is a low cost L2.5 technology (if the limited profile to be specified is implemented in isolation) that provides QoS, end-to-end OA&M and protection switching.
In February 2008 the ITU-T and IETF agreed to work jointly[1] on the design of MPLS-TP. Based on this agreement IETF and ITU-T experts will jointly work out the requirements and solutions. ITU-T in turn will update the existing T-MPLS standards[2] based on the MPLS-TP related RFCs listed below.
The following ITU-T Recommendations exist for MPLS-TP. Some of those Recommendations are superseding the ones that applied to T-MPLS before this work was ceased.
| Recommendation | Title | |
|---|---|---|
| G.8110.1[3] | Architecture of the Multi-Protocol Label Switching transport profile layer network | |
| G.8112[4] | Interfaces for the MPLS transport profile layer network | |
| G.8113.1[5] | Operations, administration and maintenance mechanisms for MPLS-TP in packet transport networks | |
| G.8113.2[6] | Operations, administration and maintenance mechanisms for MPLS-TP networks using the tools defined for MPLS | |
| G.8121[7] | Characteristics of MPLS-TP equipment functional blocks | |
| G.8121.1[8] | Characteristics of MPLS-TP equipment functional blocks supporting ITU-T G.8113.1/Y.1372.1 OAM mechanisms | |
| G.8121.2[9] | Characteristics of MPLS-TP equipment functional blocks supporting ITU-T G.8113.2/Y.1372.2 OAM mechanisms | |
| G.8131[10] | Linear protection switching for MPLS transport profile | |
| G.8151[11] | Management aspects of the MPLS-TP network element | |
| G.8152[12] | Protocol-neutral management information model for the MPLS-TP network element |
The following IETF RFCs or drafts exist for MPLS-TP:
| RFC | Title | Draft |
|---|---|---|
| Joint Working Team (JWT) Report on MPLS Architectural Considerations for a Transport Profile | draft-bryant-mpls-tp-jwt-report | |
| MPLS Generic Associated Channel | draft-ietf-mpls-tp-gach-gal | |
| MPLS-TP Requirements | draft-ietf-mpls-tp-requirements | |
| An In-Band Data Communication Network For the MPLS Transport Profile | draft-ietf-mpls-tp-gach-dcn | |
| Requirements for Operations, Administration, and Maintenance (OAM) in MPLS Transport Networks | draft-ietf-mpls-tp-oam-requirements | |
| A Framework for MPLS in Transport Networks | draft-ietf-mpls-tp-framework | |
| Network Management Framework for MPLS-based Transport Networks | draft-ietf-mpls-tp-nm-framework | |
| Network Management Requirements for MPLS-based Transport Networks | draft-ietf-mpls-tp-nm-req | |
| MPLS Transport Profile Data Plane Architecture | draft-ietf-mpls-tp-data-plane | |
| MPLS Transport Profile User-to-Network and Network-to-Network Interfaces | draft-ietf-mpls-tp-uni-nni | |
| Guidelines for the Use of the "OAM" Acronym in the IETF | draft-ietf-opsawg-mpls-tp-oam-def | |
| MPLS-TP Identifiers | draft-ietf-mpls-tp-identifiers | |
| Operations, Administration, and Maintenance Framework for MPLS-Based Transport Networks | draft-ietf-mpls-tp-oam-framework | |
| MPLS Transport Profile (MPLS-TP) Survivability Framework | draft-ietf-mpls-tp-survive-fwk | |
| MPLS-TP Control Plane Framework | draft-ietf-ccamp-mpls-tp-cp-framework | |
| A Packet Loss and Delay Measurement Profile for MPLS-based Transport Networks | draft-ietf-mpls-tp-loss-delay-profile | |
| MPLS-TP OAM Analysis | draft-ietf-mpls-tp-oam-analysis | |
| MPLS On-demand Connectivity Verification and Route Tracing | draft-ietf-mpls-tp-on-demand-cv | |
| MPLS-TP Linear Protection | draft-ietf-mpls-tp-linear-protection | |
| MPLS Fault Management OAM | draft-ietf-mpls-tp-fault | |
| Proactive Connectivity Verification, Continuity Check and Remote Defect indication for MPLS Transport Profile | draft-ietf-mpls-tp-cc-cv-rdi | |
| Pseudowire Status for Static Pseudowires | draft-ietf-pwe3-static-pw-status | |
| MPLS Transport Profile lock Instruct and Loopback Functions | draft-ietf-mpls-tp-li-lb | |
The solutions for the above requirements and framework are as mentioned below and is under development:[13]