Q: Do you have a solution for the core network ?

A: We typically integrate existing core networks (Huawei, CISCO, ZTE, VHT, etc.) unless we are deploying private networks.

The right approach depends on your specific objectives. To guide our recommendation, could you clarify the following? 

1- Do you require VoLTE/VoNR, or is an OTT voice solution acceptable?
2- Do you need to support 1,000s of subscribers or 1,000,000s of subscribers?
3- Do you need source code?

If you need to support 1,000s of subscribers, two solid options are:

- Amarisoft proprietary core network: compact, feature-rich with excellent vendor support;

- Open5GS: open-source core, well-documented by Amarisoft (https://tech-academy.amarisoft.com/MME_Open5GS.html), with additional features, though requiring more in-house effort to operate. 

If you need to support 1,000,000s of subscribers, a centralised core network approach is the recommended path. For example, we work with https://www.ouroboros.fr/, which is successfully deployed by MNOs and MVNOs in combination with ng-voice proprietary IMS or FreeSWITCH open source softswitch. We are also in contact with independent Chinese full-scale core network vendors, though we do not yet have confirmed MNO deployments to reference. 

Source code is generally available for proprietary core networks under premium licensing arrangements. 

If VoLTE/VoNR is not required, a distributed core network approach combined with an OTT voice application is worth considering - as demonstrated by NifMo in Japan. This approach reduces costs and improves resilience, but remains relatively immature and requires an app to be installed on each device. We would consider it for a greenfield network, but would not recommend it for an existing MNO with millions of subscribers or for operators requiring full 3GPP compliance.