What Qualifies as "All Fiber" for an Access Network?

Commercial disputes between competitors and partners are not unusual. But one dispute over marketing claims in the access business is unusually stretched. U.S. cable TV operator Cablevision has sued to prevent Verizon from claiming its FiOS service is “all fiber.”

The reason for the lawsuit is that Verizon uses coaxial cable for in-house signal distribution.

Cablevision has for many decades been viewed as a cable TV firm that goes its own way. When virtually all the rest of the industry was pushing for use of the 1310 nanometer optical window for optical fiber systems, Cablevision pushed for 1550 nm.

Earlier, when the rst of the industry saw satellite as a direct competitor, Cablevision was interested in satellite distribution. When it recently got into the “mobile” business, it did so using a “Wi-Fi only” approach all other service providers have eschewed.

So being different is not new for Cablevision.

Some observers might say the Cablevision lawsuit is disingenuous in a technology sense, however much sense it might make as a tactic in a marketing war. No other company has literally argued that FiOS cannot properly be called an “all optical” access system.

As any knowledgeable engineer will attest, whatever the access medium (airwaves, optical fiber or copper), the actual local connection always will use either radio (Wi-Fi) or some copper medium.

The reason is simply that no consumer device actually can accept a native optical connection.

TVs, radios, PCs, game players, cell phones, tablets, home security systems or any other connected device are unable to connect directly to an optical interface.

So it actually is disingenuous to conflate the access network with the in-home network. Not only are they separate logical, functional and legal entities, but it is literally impossible to connect any optical  facility directly to any end user device.

So “no network” could ever, in such a sense, ever be called “all optical.”

In a strict sense, “access networks” of all types are about the portion of any network that connects any single location or subscriber to the core network, typically between any location or customer and a central office, headend or cell tower.

The network beyond the cell tower, headend or central office is the “transport” network.

So the character of an access network properly concerns only that portion of the network between the customer location and the node (central office, mobile tower or headend) that aggregates traffic before it is send to the transport network.

In-home networks are traditionally and properly considered the “in-building” or local distribution network, never the access network. Ownership is one key distinction. The service supplier owns the assets all the way up the customer termination interface.

The customer owns the internal distribution network. It is the difference between the public access network and the private local area network.

Cablevision’s lawsuit, as they say, is “without merit.” Access networks are one thing; transport and in-building networks quite another.