Multi-Protocol Label Switching - Transport Profile (MPLS-TP)


Service providers are increasingly transitioning their transport architectures from circuit to packet to address the exploding demand of packet traffic and lower overall CAPEX and OPEX. Equipment manufacturers need to support these next-generation packet transport networks while maintaining the features that carriers find essential, such as comparable QoS, protection and restoration, and OAM that is available with traditional SONET/SDH and WDM/DWDM transport networks.

In these evolving networks, MPLS Transport Profile (MPLS-TP) is rapidly becoming the transport protocol of choice – as it delivers on the transport essentials in a packet architecture that is widely deployed and growing in service provider networks.

MPLS-TP Deployment Example

Network deployments of MPLS-TP enable service providers to extend the "MPLS edge" to metro and access networks, and to mobile backhaul – providing a single end-to-end MPLS-TP transport network.

Standards work on MPLS-TP began in the ITU – where it was known as T-MPLS. Responsibility now rests with the IETF, and the name has changed to MPLS-TP.


In order to make MPLS-TP better fit the carrier's requirements, it both extends and restricts the features of traditional MPLS. For example:

  • MPLS-TP adds a rich toolset of OAM capabilities, guaranteed QoS, and improved protection and restoration.
  • MPLS-TP restricts LSPs to be bidirectional and co-routed (meaning both directions follow the same path), and removes functions such as LSP Merge and Equal Cost MultiPath (ECMP).

MPLS-TP uses Generalized MPLS (GMPLS) to enable deterministic and connection oriented behavior. It can operate in two modes:

  • static provisioning of each network element
  • dynamic provisioning with a GMPLS control plane.

It is anticipated that MPLS-TP will be deployed both with and without a control plane, depending on network type (core, aggregation, access etc.) and carrier preference. Equipment vendors will likely offer both options to gain the broadest market.

Metaswitch is closely involved in the MPLS-TP standards process within the IETF. Our DC-MPLS GMPLS implementation already supports the necessary features to build a device with an MPLS-TP capable control plane, and we are adding further enhancements to meet the newest MPLS-TP standards. This allows customers to deliver MPLS-TP capable devices at the earliest opportunity.

Metaswitch has vast experience in supplying protocol software products to communications equipment manufacturers, helping them build access, aggregation and transport devices. We are far and away the leaders in portable GMPLS solutions. Our DC-MPLS product, in combination with DC-OSPF and DC-ISIS, provides a complete solution that can be used in MPLS-TP compliant devices.