It may be ancient history, but it’s interesting to remember that the original aim of telephone industry digital subscriber line (DSL) developers was to counter cable operators by offering video programming over phone lines. Of course, DSL proved unable to do this effectively. However, it found fame and fortunate as a generic broadband conduit. Though it slowly is moving into its sunset years, it remains a vibrant element of the telecommunications landscape long after its introduction.

The moral of the story is that a technology that hangs around long enough may find some success, even if it is for a purpose other than that for which it originally was intended.

This might be happening with broadband over powerline. BPL initially was devised as a way to provide broadband service to rural and underserved areas. Though the speed was never thought likely to equal other forms of broadband, the big advantage was its almost complete ubiquity. That and the fact that cable and telephone companies largely disenfranchised folks in the hinterlands made it an intriguing platform.

It didn’t happen. Muddled business cases, interference issues, the entrenched enmity of amateur radio operators, the widespread deployment of faster forms of broadband and general inertia made it forever seem likely to be a marginal approach.

There may be life in BPL yet, however. The platform may find a second -- or, really, first -- life as a supporter of smart grids. BPL’s ubiquity advantages certainly play well here. The problem of limited throughput is obviated by the fact that smart grid simply doesn’t involve the transfer of that much data. The bandwidth necessary to shut down a refrigerator isn't quite as much as that needed to transmit "The Matrix" in high definition.

In addition, BPL fits well with the broadband element of the economic stimulus package, as EDN's Brian Dipert points out. There is some movement on the BPL standards front. TG Daily reports that The Institute of Electrical and Electronics Engineers’ P1901 Working Group has released a draft defining the media access control (MAC) and physical layer specifications of the proposed standard. The story says that the draft meets more than 400 requirements, is appropriate for local-area networks (LANs), smart grids and broadband, and can provide bandwidth of more than 100 megabits per second, presumably to groups of homes or businesses.

In June, the Organisation for Economic Co-operation and Development released a report entitled "Broadband Over Powerlines: Developments and Policy Issues." Last month, CircleID summarized the main points from the report. It’s interesting in both what is says and what it doesn’t. The report – or, at least, the report on the report – pays lip services to the potential for BPL to be an enabler of smart grid. But then the writer dives deeply into the obstacles that have kept the platform from any sort of success. The OECD recommends a “technology-neutral policy” that would not place additional obstacles in the technology’s path. It’s interesting, though, that a bit more is not made of the seemingly good match between BPL and smart grid.

This IEEE news podcast by Francesco Ferorelli also sees the possible use of BPL to enhance smart grid. He points out that money is saved by using pre-existing infrastructure. Ferorelli points to a project by International Broadband Electric Communications that brings 3 Mbps service to areas with as few as three houses per kilometer.

Of course, it remains to be seen if smart grid is the killer app that can save BPL from what appeared to be its long goodbye. If it is, however, it wouldn’t be the first time that a technology was saved by an applications for which it initially was not intended. Just ask the DSL folks.