My friend: Hi Ibrahim, I have a question for you.
- Me: You are most welcome, go ahead.
My friend: I am hearing a lot about cloud RAN, vRAN and Open RAN, but I don’t understand what is the difference between them, could you shed some light on it?
- Me: Sure, let me start with Open RAN which its target is openness by making all the interfaces between all the RAN elements (RU, DU, and CU) open interfaces, so you can buy any RAN component from any vendor and when you connect all these RAN components together, they are working perfectly, as if they are from the same vendor, because they are interoperable. Thus, let me say that Open RAN provides you with the horizontal flexibility. Of course, there is another target for Open RAN which is intelligence, by introducing RIC (RAN Intelligent Controller) for both near-real time and non-real time services to introduce AI/ML to enhance the radio performance.
My friend: So, what about Cloud RAN?
- Me: Cloud RAN refers to the RAN that is following the cloud-native approach which means the DU and CU functions are implemented as a software over a general purpose HW from any vendor and this setup is implemented using containers, microservices, CI/CD, automation, and many of the cloud-native principles. So, let me say that Cloud RAN provides you with the vertical flexibility. And be ready to hear a lot about Cloud RAN at the next period as it’ll be the main target for many MNOs to implement.
My friend: So, that means vRAN is a type of Cloud RAN, right?
- Me: No, vRAN is a step lower than Cloud RAN as vRAN offers SW disaggregation from HW which means we can have the DU and CU as a SW functions implemented using virtualization technique over a general purpose HW from any vendor. However, it doesn’t follow the cloud-native principles mentioned above. And if you remember our last discussion, we mentioned that virtualization is the 2nd step in our road for the cloud-native transformation which was consisting of 4 steps. (link for this discussion will be in the 1st comment).
My friend: So, can all these RAN techniques be implemented together?
- Me: Yes, Cloud RAN is an evolution from vRAN, and many vendors are investing in Cloud-Native Open RAN solutions where the Open RAN approach is available with the cloud-native approach as well to offer the best performance specially in the 5G world.
My friend: Thank you very much, you made it very clear.
- Me: You are most welcome.