Infinera Technology

Since the mid-1990s, optical telecom equipment vendors have envisioned an all-optical future. According to this vision, amplifiers, filters, and mirrors have replaced all electronics in networks, seamlessly transporting digital services as waves of light. It's an attractive idea, since the translation between optical and electrical domains—the so-called "O-E-O" conversion—historically accounts for the bulk of network costs. If the O-E-O conversion is so expensive, why not get rid of it?

It turns out there's a catch: Digital processing requires electronics. Get rid of the electronics, and you also get rid of the "digital"—which is a significant drawback given that almost all the information carried by the optical network originates in digital form. In contrast, the all-optical network is also all-analog. As the optical layer becomes more analog, it becomes more complex, more sensitive to noise and impairments, less flexible to new customers or new services, and more painful to engineer, deploy, manage, and evolve. Similar issues caused carriers to transition their voice, video, and mobile wireless networks from analog to digital. Yet the optical network seems headed in the opposite direction.

Does it have to be this way? Must the dream of an all-optical future turn into an all-analog nightmare?