Fixed-Mobile Convergence in the 5G Era: From Hybrid Access to Converged Core

The availability of different paths to communicate to a user or device introduces several benefits, from boosting end-user performance to improving network utilization. Hybrid access is a first step in enabling convergence of mobile and fixed networks; however, despite traffic optimization, this approach is limited as fixed and mobile are still two separate core networks inter-connected through an aggregation point. On the road to 5G networks, the design trend is moving toward an aggregated network, where different access technologies share a common anchor point in the core. This enables further network optimization in addition to hybrid access; examples are user-specific policies for aggregation and improved traffic balancing across different accesses according to user, network, and service context. This article aims to discuss the ongoing work around hybrid access and network convergence by the Broadband Forum and 3GPP. We present some testbed results on hybrid access and analyze some primary performance indicators such as achievable data rates, link utilization for aggregated traffic and session setup latency. We finally discuss future directions for network convergence to enable future scenarios with enhanced configuration capabilities for fixed and mobile convergence.