What are the different deployment scenarios of Cloud RAN?
My friend: Hi Ibrahim, I have a question for you.
Me: Go ahead, please.
My friend: I was wondering how Cloud RAN can be deployed. Is it one scenario only? Or can we have multiple scenarios?
Me: Cloud RAN can be deployed in different scenarios. Let’s start with the most common one which is the distributed RAN which can have two options, the 1st one is to have both DU and CU on the cell site and here we can use the purpose-built RAN option as the big benefits of Cloud RAN are not relevant. The 2nd option is to have a distributed DU located at the cell site, while the CU is centralized and here you gain the benefits of pooling the resources of CU against multiple DUs and also the performance gain as well. Moreover, we’ll have a more unified operational model, but at the expense of increased system integration complexity.
My friend: So, what are the other scenarios to deploy Cloud RAN?
Me: Cloud RAN can use the centralized RAN deployment where both DU and CU will be located in a central location, such as “central offices”. Here, we need to design the fronthaul capacity and latency very well to guarantee that performance is not affected by this setup. The pooling gain of CU and DU resources will add a great benefit and will reflect in lower cost as we don’t need to have a spare capacity in each site to cater for the high peak load. Also, as the DU and CU are moved away from the cell site, so that means reduced site rental and less energy consumption. Note that it’s not necessarily that DU and CU be in the same location as DU can be moved to a far Edge location near the cell site, while CU can be kept in central location in case low latency is required.
My friend: Now, I think we finished all deployment scenarios, right?
Me: No, there is still one last type of deployment which is on-premises network deployments or private capacity networks where a 5G network is dedicated for an enterprise customer. Here the DU and CU will be hosted in the customer premises. Also, the Core network could also be deployed on-premises, which makes it possible to secure sensitive and sovereign data locally and cater for low-latency use-cases.
My friend: Thank you very much, you made it very clear.
Me: You are most welcome.
