SDN-based WAN optimization: PCE implementation in multi-domain MPLS networks supported by BGP-LS


  • Grzegorz Rzym
  • Krzysztof Wajda
  • Piotr Chołda


In order to provide efficient and flexible resource management and path set-up in high-speed MPLS/GMPLS networks, the PCE (Path Computation Element) architecture was proposed by IETF.
Implementation of a central module for the path set-up enables network operators to run path establishment operations for applications with explicitly defined objective functions and QoS requirements.

The paper reports on recent research and experimental investigations with PCE-based path computation performed according to the 3-layered traffic engineering (TE) system consisting of: (1) a PCE module equipped with the IBM Cplex LP solver used in the highest layer 3, and (2) a SDN controller in the intermediate layer 2 responsible for transferring path set-up requests towards virtual routers in the lowest layer 1.

The presented results show usefulness of the PCE-supporting architecture with an SDN controller and applicability of bandwidth-oriented optimization based on real-time focused constraints (path delay limits).


Cui L., Kumara S., Albert R. (2010). Complex Networks: An Engineering View. In IEEE Circuits and Systems Magazine, 10(3):10–25.

Farrel A., Vasseur J.P., Ash J. (2006). A Path Computation Element (PCE)-Based Architecture. RFC4655.

Fonoberova M., Lozovanu D.D. (2005). Algorithms for Finding Optimal Flows in Dynamic Networks. In Computer Science Journal of Moldova, Institute of Mathematics and Computer Science.

Fortz B., Thorup M. (2000). Internet Traffic Engineering by Optimizing OSPF Weights. In Proceedings IEEE INFOCOM, Tel Aviv. pp. 519-528, vol.2.

Fortz B., Thorup M. (2002, May). Optimizing OSPF/IS-IS Weights in a Changing World. In IEEE Journal on Selected Areas in Communications. 20(4):756–767.

Gredler H., Medved J., Previdi S., Farrel A., Ray S. (2016). North-Bound Distribution of Link-State and Traffic Engineering (TE) Information Using BGP. RFC7752.

King D., Farrel A. (2012). The Application of the Path Computation Element Architecture to the Determination of a Sequence of Domains in MPLS and GMPLS. RFC6805.

Medved J., Varga R., Minei I., Crabbe E. (2016, December). PCEP Extensions for Stateful PCE. IETF


Paolucci F., Cugini F., Giorgetti A., Sambo N., Castoldi P. (2013). A Survey on the Path Computation

Element (PCE) Architecture. In IEEE Communications Surveys and Tutorials, 5(1):2–13.

Pioro M., Medhi D. (2004). Routing, Flow, and Capacity Design in Communication and Computer Networks. Morgan Kaufmann Publishers Inc., San Francisco, CA, USA.

Le Roux J.L., Vasseur J.P., Lee Y. (2009). Path Computation Element (PCE) Communication Protocol (PCEP). RFC5440. [12] Le Roux J.L., Vasseur J.P. (2009). Encoding of Objective Functions in the Path Computation Element Communication Protocol (PCEP). RFC5541.

Varga R., Minei I., Sivabalan S., Varga R. (2017, January). PCEP Extensions for PCE-initiated LSP Setup in a Stateful PCE Model. IETF draft.

Vasseur J.P., Zhang R., Bitar N., Le Roux J.L. (2009). A Backward-Recursive PCE-Based Computation (BRPC) Procedure to Compute Shortest Constrained Inter-Domain Traffic Engineering Label Switched Paths. RFC5441.

Xia W., Wen Y., Foh C.H., Niyato D., Xie H. (2015). Survey on Software-Defined Networking. In IEEE Communications Surveys and Tutorials, 17(1).

Open Networking Foundation: Software-Defined Networking: The New Norm for Networks. ONF White Paper, 2012. (2017, February). (2017, February)






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