ECI's White paper:
DIM Fiber Services
In between dark fiber services and lit services lies a lesser known set of services known as “dim” services. Less expensive to maintain than lit services but with more options and higher revenue than dark fiber, dim services are an ideal service for many fiber network operators and their customers.
A dim service is not a service offered by or to “dim” operators. In fact, dim services are exactly the opposite – they have value for smart, discerning operators who want to find just the right option for their network needs.