Overview

The IPM-1SE provides a type of pseudo wire (PW) function where a real-time bit stream (TDM) is transmitted over a packet switched network (PSN). By TDM (Time Division Multiplexing) we mean a T1 or E1 signal, while the PSN is based either on an IP or raw Ethernet network. Unlike other traffic types that can be carried over pseudo wires (e.g. ATM, frame relay, and Ethernet), TDM is a real-time bit stream, which traditionally carries voice-grade telephony channels. One critical issue in implementing TDM over IP is clock recovery. In native TDM networks the physical layer carries highly accurate timing information along with the TDM data, but when emulating TDM over Packet Switched Networks this synchronization is absent. The IPM-1SE is able to accurately regenerate the timing signals to the exacting standards and conformance with ITU-T. As core networks continue their conversion from traditional switched technology to IP based networks, the IPM-1SE provides a solution to continue using legacy TDM equipment, such as PBX, while still using IP based networks for.