The Smart Grid Interoperability Panel Governing Board has officially approved the Internet Protocol (IP) as its standard protocol for applications! While standardizing on anything but IP would certainly not have been smart, the obvious needed to be firmly stated. The Internet Protocols for the Smart Grid document referenced in the approval is an Internet draft, but it will likely gain IETF approval as an RFC in the near future.
The draft is intended to provide Smart Grid designers with the core set of protocols on which to develop products and services and it covers UDP and TCP at the transport layer and IPv4 and IPv6 at the network layer, though it includes broad coverage of related protocols such as routing protocols, DNS, DHCP and network management protocols.
While some in the industry had advocated stronger wording around recommending the use of IPv6 over IPv4, given the relative scarcity of available public IPv4 address space, the document is non-judgmental on this point. And as a document defining the suite of available protocols, I agree with the approach. The debate about when and how to roll out IPv6 rolls on, though as smart meter deployments continue, IPv6-only addressable devices will soon arrive on the Internet!