Statistical Analysis of end-to-end Route Feasibility in Converged Metro–Access Optical Networks

Disaggregation of the Radio Access Network (RAN) imposes stringent fronthaul latency and physical-layer performance requirements on supporting the optical transport infrastructure. This paper evaluates the feasibility of Access–DU–Access (A–DU–A) routes in a converged metro–access optical network, jointly considering Bit Error Rate (BER) and the fronthaul latency constraint of 250 μs, considering functional split 7.2 defined by 3GPP. Two deployment scenarios are examined: (i) DU/CU hosting at metropolitan Points of Presence (PoPs) and (ii) DU/CU hosting at external data centers (DCs). Using Cassini and Phoenix whiteboxes hosting pluggable DCO transceivers (TRxs), the analysis quantifies the impact of modulation format, BER thresholds, and end-to-end propagation latency on service feasibility. Results show that metro-based hosting supports 87.9% latency-compliant routes compared to 47.6% under data-center hosting, and that Cassini consistently provides higher BER feasibility across modulation formats. The findings demonstrate that physical-layer impairments and functional placement must be jointly optimized to support latency-constrained, virtualized RAN transport in converged metro–access networks.