The Zigbee Alliance this week announced it is well along in the development of a wireless neighborhood area network (NAN) to provide local access and management of Smart Grid power management services.
According to Tobin J.M. Richardson, President & CEO of the ZigBee Alliance, a group of leading smart metering and smart grid member companies are developing a communication profile aimed at achieving true plug-and-play interoperability between the members’ wireless smart grid Neighborhood Area Network (NAN) products and solutions (Figure 1 ).
Figure 1. The Zigbee Alliance effort is to build a last mile specification for wireless connectivity to the Smart Grid.
The NAN standardization work is anticipated to be completed by the end of 2014 and will include the Technical Specification, Protocol Implementation Conformance Statement (PICS) and Certification Test Plan.
“The NAN is defined as a utility’s last-mile, outdoor access network,” he said, “that connects smart meters and distribution automation devices to Wide Area Network (WAN) gateways such as RF collectors or data concentrators and field devices.”
To date, he said, the definition and documentation of the market requirements and the detailed technical requirements for the NAN has been completed.
Also, a number of ‘proof of concept’ events to test the interoperability of the PHY/MAC functions that will be included in the NAN standard have been held during the past year at which participants’ NAN products were able to communicate with each other through the PHY/MAC layers.
In addition, said Richardson, several companies demonstrated interoperability for basic IP functions. The NAN standardization work is anticipated to be completed by the end of 2014 and will also include the Technical Specification, Protocol Implementation Conformance Statement (PICS) and Certification Test Plan.
He said there is a global requirement from regulators and utilities for standards-based interoperable NANs that will provide utilities with wider choice of product features, increased price competition, reduced supply risk and flexibility in selecting vendors.
To ensure that all their products will interoperate seamlessly, the effort is to develop such a local network scheme that depends of existing IEEE and IETF standards.
But Richardson emphasized that such standards on their own do not ensure interoperability due to the many options available within the standards.
“The NAN specification will fill the gap by selecting the most appropriate options between standards and defining a communication profile with certifiable interoperability,” he said. “This will be a significant improvement for utilities when compared with the non-interoperable, proprietary single-vendor solutions available today.”
In order to ensure interoperability, a full wireless communications protocol is being defined for Layers 1 through 4 of the ISO OSI communication stack.
Richardson said this will provide a harmonized transport network supporting different IP-based applications. Layers 1 and 2 will be based on the IEEE 802.15.4g amendment to the IEEE 802.15.4 (2011) standard that was introduced to enable the development of interoperable NANs.
Layers 3 and 4 will be based on IEFT standards including the IPv6 network layer and associated networking schemes, appropriate routing and transport protocols (e.g., RPL, UDP and TCP) and relevant security mechanisms.
“This wireless communications profile will enable interoperability between different vendors,” he said, “who have all implemented their smart meters, smart grid devices and communication infrastructure node products according to the certifiable NAN communications profile.
Current smart grid applications such as smart metering and distribution automation will run on top of this interoperable wireless IPv6 communications profile.
A key aspect of this NAN standardization work is to establish a test and certification program supported by independent test houses with the aim of certifying the interoperability of different manufacturers’ smart grid products and solutions.
“The ZigBee Alliance will maintain a register of certified smart meter and smart grid products in order to provide confidence for utility customers when making their smart grid vendor selections,” said Richardson.