In the weeks since our smart grid networking and communications report was released, we’ve had some interesting industry reactions. Some press folks and, well, utilities just ask “which technologies are the winners and which are the losers?” Perhaps anticipating this, vendors have been quick to reinforce how their particular networking flavor is better than their competitors.

Technically, there are many potential points of comparison, including bandwidth, latency, range (particularly for wireless), reliability, security, and of course, cost. Since the suitability of any given technology depends on application requirements, we outlined the key smart grid applications and their requirements: HANs, AMI NANs (Neighborhood Area Networks), AMI backhaul, Distribution Automation WAN, and Substation Automation WAN. We defined the requirements rather broadly, as they vary considerably on a case-by-case basis. We then surveyed over 16 different communications technologies and outlined their attributes against these applications requirements.

The complications arise when trying to offer summary comparisons between the technologies, as attempted in the nearby table. For example, bandwidth might seem like a straightforward metric to characterize, however the bits-per-second of a link may be a poor predictor of actual application throughput. Node-to-node performance in a mesh network is highly dependent on the number of hops and link contention within these hops. Depending on customer deployment decisions, a network with 19.2 kbps links could outperform a network with >100 kbps links. Extending this logic, a star-based topology, such as a 3G public network, might then seem better compared to a mesh. And yet, the latency across an IEEE 802.11 broadband mesh (aka “metro Wi-Fi”) may still be an order of magnitude less than that of a public wireless network when all the access protocols and various backhaul networks hidden within a public network are factored in. And some technologies may offer a wide range of bandwidth options depending on range (e.g. WiMAX) or cost (e.g. satellite). Which data point to choose for a comparison? Even cost has many variables: the cost of fiber cable and equipment continues to drop, but that hardly matters if digging up an interstate highway or crossing a mountain range in order to install it.

The bottom line, as we are careful to point out in our report, is that any summary comparison needs to be understood only as a starting point. Ultimately, for any given project, the various choices – technology and individual vendor – need to be evaluated against carefully constructed use cases. As for winners and losers, there are some general principles that do seem to universally apply:

1. Standards are important. If the evolution of data and telecom networks have demonstrated anything, it is that proprietary technologies invariably yield to industry standards. Distressingly, the largest smart grid application in terms of number of nodes (smart metering and AMI), is the least standardized. This will change.

2. Security must be baked in. A secure network means much more than having a bit of link encryption or vague support of the “IP security suite”. It must include a comprehensive end-to-end security regime including strong key management, and is a business process issue as much as a technical concern.

3. Evolution flexibility trumps application-specific bells and whistles. The smart grid is a big, long-term endeavor, and none of us really knows quite where it will lead. Flexible layered network architecture is key to accommodating as yet unforeseen changes.

So, while our report may imply some winners and losers within our per-application forecasts for each of the 16+ smart grid networking technologies, ultimately, it is up to you to pick the ‘winner’ for your application. I hope we can help, and good luck!