t is crucial to understand the details of these procedures to be able to design and implement an NSA network. Similarly, there are further details available in the specifications for specific call flows for the other deployment options, which can be referenced for further reading. Advantages and shortcomings The main advantage of deploying an NSA-based network is the speed of deployment, which drastically reduces the time to market. This architecture enables service providers to provide 5G services by merely upgrading the RAN to NR while using the EPC from the legacy 4G infrastructure. This also reduces the cost of deploying 5G. This is a good option for transitioning to a fully fledged 5G SA network with a 5G core. The main disadvantage is that it is limited in support of 5G use cases. This option can support enhanced broadband-based use cases. However, the more advanced Ultra-Reliable Low-Latency Communications (URLLC) use cases, live Vehicle-to-Vehicle (V2V) communications, and use cases leveraging network slicing would need an SA network. Summary We have seen by now that the push for NSA networks comes from the strong desire of the industry to accelerate the standardization of NR architecture SO that the time to market can be cut down. The greatest advantage is the ability to leverage existing legacy network infrastructure. NSA access was standardized in 3GPP Release 15 in December 2017. In this chapter, we have covered a typical NSA network in detail. We have discussed the different bearers such as MCG, SCG, and split bearers. We have also explored the other available deployment options and their key features. We explored the various migration paths from the EPS network to 5G and finally, we delved into a detailed 5G-NSA call flow. We concluded the chapter by briefly discussing the advantages and disadvantages of the NSA network. In the next chapter, we will learn about the design and implementation of a typical 5G SA network and delve into the details of its procedures. 5G Standalone Networks In this chapte