Evaluating transmission performance for migration from SDH/PDH networks to MPLS-TP and IP networks

(SDH) and Plesiochronous Digital Hierarchy (PDH) technologies in electric power telecommunication networks, they plan to migrate from SDH and PDH to Multi-Protocol Label

Switching-Transport Profile (MPLS-TP) or IP networks to realize the next-generation telecommunication networks. However, most electric power system devices connected to SDH or PDH networks are not equipped with Ethernet/IP interfaces (IFs). To support legacy transmission telecommunication services (e.g., Time Division Multiplexing (TDM) and

SONET/SDH) over packet-switched networks, Pseudo Wire Emulation Edge-to-Edge (PWE3) has been standardized by the IETF (RFC 3985). By applying PWE3, operational data from such devices can be transported over MPLS-TP or IP networks. Accordingly, it is necessary to evaluate the transmission delay time performance of EPU applications over MPLS-TP and IP networks with PWE3 and to confirm that delay time requirements are met.

This paper evaluates three representative EPU applications: a protection relay device, an analogue telephone device, and a remote supervisory and control device. We configured MPLSTP and IP test networks with PWE3 and measured the end-to-end delay time for each application. The results demonstrate that application delay time over MPLS-TP and IP networks with PWE3 meets the requirements, indicating that electric power system operation can be maintained following migration.