Network Technologies for Heterogeneous and Converged Connectivity: A Comparative Survey
Modern connectivity is supplied by a portfolio of technologies rather than by a single dominant network. Ethernet and passive optical networks provide stable high-capacity infrastructure; Wi-Fi supplies flexible local access; cellular systems add managed mobility and wide-area coverage; low-power wide-area networks support constrained sensing; and non-terrestrial networks extend service beyond economical terrestrial reach. Meanwhile, time-sensitive networking, deterministic networking, software-defined networking, network functions virtualization, slicing, and edge computing reshape how access technologies are assured and combined. This survey develops a three-layer taxonomy that separates transport, assurance, and control or service functions, then compares major technology families across capacity, latency, reliability, range, mobility, energy, economics, security, interoperability, and maturity. A structured narrative review of standards and peer-reviewed literature is used to identify recurring trade-offs and deployment boundary conditions. The synthesis shows that performance claims are meaningful only when topology, workload, channel, ownership, and failure assumptions are explicit. No family dominates the complete design space: emerging systems are heterogeneous by construction and increasingly depend on cross-domain orchestration. The paper concludes with application mappings and a research agenda centered on verifiable end-to-end guarantees, trustworthy automation, zero-trust identity, sustainable operation, and reproducible evaluation of 5G-Advanced and prospective 6G systems.