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Multi-Network Access: How It Can Benefit Network Operators and Consumers Alike

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posted on 22.01.2020 by Nandi Zhang
Consumers today are often simultaneously covered by multiple wireless communications networks that vary in throughput, latency, price, coverage, etc. Despite that, today's wireless services and mobile devices are set up to use the same network as long as that network is available, or to only communicate via Wi-Fi as long as a known Wi-Fi network is present. In this thesis, we show that there can be huge benefits to the alternative scheme, multi-network access (MNA), where a mobile device may use the infrastructure owned by any one of multiple network operators, at any point in space and time.
MNA can greatly improve the spectral efficiency of cellular networks. Given uniformly distributed tower location, MNA can increase network capacity by over 50% without additional infrastructure or spectrum; or equivalently, it can reduce infrastructure and spectrum spending each by 20% to produce the same capacity. The benefit of MNA is accessible - it does not require large separation distance between the transmitters belonging to different network operators, nor does it require many non-colocated transmitters. Moreover, colocation does not necessarily negate the benefit of MNA; they can be deployed together to achieve even greater cost efficiency.
The economic impact of MNA on individual network operators is a result of both business decisions and technical parameters. When mobile network operators (MNOs) participate in MNA, the distribution of traffic volumes and the associated revenue among partner MNOs with MNA is not necessarily equal to that without MNA, and is not necessarily commensurate with the distribution of investment on infrastructure and spectrum resources among partner MNOs. There exists MNA arrangements that make all stakeholders, including consumers, better off; exactly how these benefits are distributed among all stakeholders comes down to negotiations.
MNA-capable users can benefit from higher-layer protocols and features that enable the fast switching between networks without disruption to ongoing sessions and the better utilization of multiple networks. Flow-level migration allows fine-grained load balancing and QoS matching for multihomed devices running heterogeneous applications. Locators based on directed-acyclic-graphs allow quick response to link failure and enhances the resiliency of multihomed hosts and networks. Self-certifying identifiers facilitate authentication of migration signaling messages and helps reduce handoff latency.
MNA already exists today in the form of a multi-operator mobile virtual network operator (MO-MVNO) like Google Fi, and there are signs of growing momentum in other forms such as through dual-SIM phones. The advent of 5G and network slicing thanks to software defined networking (SDN) and network function virtualization (NFV) technologies will make MNA even more relevant in the future. MNA may have a profound impact on our wireless internet services by bringing a fundamental shift in control from service providers to end users. Consumers will no longer be limited by a single service provider in price, coverage, performance and customer service, and can always receive the service that best meets current needs. While practical barriers to MNA remain, the potential economic and social benefits provide strong incentives for its consideration.




Degree Type



Engineering and Public Policy

Degree Name

  • Doctor of Philosophy (PhD)


Jon Peha Marvin Sirbu