NTT DOCOMO deployed the 5G Core network (5GC) to provide 5G SA and launched commercial services for enterprise customers in December 2021.
5GC leverages advanced technologies such as SBA and container infrastructure, which will enable the creation of new value required for networks in the 5G era, such as network slicing.
This article describes details of these technologies.
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https://www.docomo.ne.jp/english/corporate/technology/rd/technical_journal/bn/vol24_4/001.html