Lit fiber is the ordinary case: the provider has put light on the fiber and sells you capacity across it. You receive an Ethernet handoff at an agreed rate and the provider owns everything underneath — the optical equipment, the monitoring, the fault handling, and the service commitment.
Dedicated internet access, point-to-point circuits, wavelengths, and Ethernet transport are all lit services. They differ in what they connect and at which layer, but they share the property that the provider operates the transmission equipment and is accountable for the circuit working.
On a lit service, increasing capacity is a provider action — sometimes a configuration change on existing equipment, sometimes an optics change, occasionally a new build if the handoff cannot carry the target rate. Establishing the ceiling of the installed handoff at order time saves an unwelcome conversation eighteen months later.
This is the practical advantage. When a lit circuit misbehaves, one organization owns the diagnosis from your handoff to the far end. On dark fiber that responsibility splits at the glass, which is manageable if you have the staff and painful if you do not.
A lit service is priced on the committed rate and the term, so the recurring cost tracks the bandwidth you buy rather than the fiber it rides on. Dark fiber is priced on strand-miles and term instead, which is why the two cross over at some combination of distance and capacity. Working out where that crossover sits for a specific route is a more useful exercise than arguing the merits of either in the abstract.
Lit fiber is the right answer for the large majority of organizations, including many that initially ask about dark fiber. The comparison worth running is total cost of ownership across the actual requirement — equipment, spares, monitoring, and engineering time included — not a lease rate against a monthly circuit charge.
Lit Fiber is one of the specifications these comparisons turn on.
Describe the requirement and an engineer will tell you which service actually fits — without a rate card or a sales script in the way.
Service availability depends on location, network proximity, capacity, and engineering review. Share an address and we will confirm what can be delivered there.