Three Steps for TDM migration to IP/MPLS

Currently most operators rely on SDH/SONET networks as their transmission backbone. These TDM-based networks have proven reliable, resilient and secure over the years for delivering voice, video and data traffic, including SCADA and private mobile radio/land mobile radio (PMR/LMR).

TDM equipment is being phased out, however, and newer applications are requiring more than TDM can give; the future of operator networks is undeniably IP/MPLS, as it better serves geographic information systems, high resolution video protection, 4G/LTE (News - Alert) connectivity and machine-to-machine communications.

A network transformation is coming, and operators are weighing their option on how to leverage the transformation for various industries.

Alcatel-Lucent (News - Alert) (ALU) works extensively with both TDM and IP/MPLS network design. And, a recent ALU white paper, “Transformation of mission-critical communications networks: Migrating from SDH/SONET networks to IP/MPLS networks,” gives some guidance for operators and they consider their network migration from SDH/SONET TDM-based networks to IP/MPLS.

“The goal is to keep the disruption of existing applications to a minimum,” the white paper advises. “We recommend that the migration from SDH/SONET to MPLS take place in phases.”

First, operators should add IP/MPLS routers to their SDH/SONET infrastructure.

“This allows the introduction of new IP services and Ethernet connectivity while continuing to support TDM services on the SDH/SONET infrastructure, for cost savings and reduced disruption,” the paper notes.

Second, switch TDM services to the IP/MPLS infrastructure. This migration can be done in stages and with the coexistence of various interface types, according to Alcatel-Lucent. Services that have been satisfied with traditional TDM interfaces can also be supported while new Ethernet interfaces for these services are being introduced.

Third, when making their network transformation, operators should then remove the SDH/SONET infrastructure and introducing wavelength division multiplexing (WDM).

“This simplifies network structure and management while providing an infrastructure capable of supporting new services and their bandwidth requirements,” as the paper notes.

The network migration from TDM to IP/MPLS is not a quick one, but is necessary for the future of an operator’s competitiveness.