T1, Ethernet or IP/MPLS: The SCADA Data-Transport Protocol Debate for Power Utilities

A debate in power utilities today focuses on supervisory control and data acquisition (SCADA) traffic. What solution offers the best reliability and security for transporting SCADA? T1? Ethernet? Or IP/MPLS?

Recently, I presented on SCADA at the Utilities Telecom Council (UTC) conference. UTC members wondered aloud how they can boost the capacity and capabilities of their communications infrastructures.

Actually, there’s no one-size-fits-all answer to the SCADA question.  For a given utility, the best SCADA data-transport protocol depends on 2 other issues. First, what are your utility's overall communications needs? Second, what’s your business model?

T1, Ethernet or IP/MPLS?SCADA transport factors into network migration strategies, but it does not require high bandwidth. However, you also need to consider traffic-generating applications such as smart meters and video surveillance.

As you migrate to data-transport solutions, you’ll find Ethernet interfaces on lots of new equipment. So you need solutions that deliver more bandwidth and Ethernet data transport.

Business models vary from utility to utility. Some utilities use installed fiber to provide telecom services — wholesale, retail or both.  Utilities with a dual business model must keep pace with customers' bandwidth and data-transport demands, as well as their own.

Before deciding on one or more data-transport protocols, you must address other questions:

  • Do you want to deploy a converged network to support multiple services, including SCADA?
  • Which solutions can keep your SCADA traffic separate to comply with regulatory requirements?
  • Do you want to build a network dedicated only to SCADA traffic?

No matter which data-transport technologies you choose, you have two more things to figure out. First, how will you manage the new network? And what impact will the solution(s) have on your day-to-day operations? 

Many existing utility communications networks are based on TDM and SONET. So you need to ensure that your support people understand the data side of the network, both during the migration process and after it’s completed.