From Technology Integration To Segment-Level Substitution: Rethinking Hybrid Fiber– Wireless Access Network Design

Hybrid fiber–wireless access networks are commonly framed in the literature as systems that integrate heterogeneous technologies to extend coverage or improve performance. While this integration-centric perspective has yielded important architectural innovations, it has also ob-scured a more fundamental driver of real-world broadband deployment outcomes: the asymmetric concentration of cost, time, and operational constraints across network segments. This paper proposes a conceptual shift from “technology integration” toward “segment-level substitution” as the dominant logic for hybrid access network design. Drawing on broadband deployment litera-ture, techno-economic studies, and infrastructure management theory, the paper argues that hybrid architectures are most effective when wireless technologies are selectively substituted for optical fiber in constraint-heavy access segments, rather than uniformly integrated across the network. A segment-based analytical model is developed to distinguish feeder, distribution, and access com-ponents of passive optical networks (PON), and to explain why deployment inefficiencies dis-proportionately arise in the last-mile segment. The paper introduces the concepts of constraint concentration and feasibility-gated substitution to formalize when and where wireless access can outperform fiber on deployment efficiency dimensions without compromising service require-ments. By reframing hybrid access networks as decision problems rather than purely technical architectures, the paper contributes to hybrid networking theory, broadband infrastructure eco-nomics, and strategic network planning. The framework provides a foundation for future empiri-cal validation and informs both operator strategy and public broadband policy.