There’s a (relatively) new acronym making the rounds: RFOG, or RF Over Glass. In brief, RFOG is a category term for technology that lets cable operators use traditional back-office cable equipment with new fiber-to-the-home deployments. In greenfield situations, even cable operators want to put fiber in the ground, but they’d rather not pay for the other network upgrades that go with it. It’s cheaper and easier to stick with coax if it means they can use existing infrastructure gear and management tools. In other words, there’s incentive to choose coaxial cable over fiber unless you solve the back-office problem. Which is where RFOG comes in.
RFOG is a good thing, but the term may also be used to muddy the marketing waters. It’s good because using an RF overlay makes it financially feasible for operators to deploy deep fiber. On the other hand, RFOG includes many of the same limitations faced on a traditional coax network. There’s virtually no bandwidth gain (unlike with passive optical networking), despite the fact that operators can market the technology as fiber to the home. Ah, marketing.
At the moment, RFOG is a standard in development. (Yes, Motorola is part of that development process.) Ideally, RFOG should act as an intermediate step on the way to passive optical networking (PON), but unless there are clear and open parameters for how RFOG must work, there is no guarantee that today’s RFOG deployment will migrate well to a future PON architecture, or that operators won’t be locked in to a single vendor’s technology.
It’s hard to be brief on a subject this convoluted, but here a couple of key points:
- As pressure builds for FTTH deployments (especially in new residential areas), RFOG will provide cable operators a viable fiber solution, even if it doesn’t provide the bandwidth benefits of PON.
- Operators should keep their eyes wide open when choosing a solution labeled RFOG. There is no agreed-upon standard yet, and anything deployed today needs to leave an operator’s options open for upgrades tomorrow.