Hi Tom,
For 5G, the Native Telco Cloud is a mandatory requirement. Innovative green fielders can use a complete Cloud OSS/BSS stack. Existing incumbents / CSPs will still use their existing legacy OSS/BSS stack. Porting OSS/BSS to a Cloud environment will be a part of an agreed business Transformation Programme.
Reference:
https://www.datacenterdynamics.com/opinions/what-role-will-vrans-play-our-5g-future/
VBR/ Wallis Dudhnath