# <center><i class="fa fa-edit"></i> Introduction to Open RAN </center>
###### tags: `Theory`
:::info
**Goal:**

- [x] Introduction to O-RAN
- What is the Disaggregation of The Core Network?
- What is the Open RAN and How Does it work?
- How is the evolution of Open RAN?
- What is RAN Architecture?
- What is White box RAN?
- What is O-RAN Allience?

**Resources:**
* [Introduction to open RAN](https://www.brighttalk.com/webcast/16515/359818?utm_source=brighttalk-portal&utm_medium=web&utm_content=Parallel%20Wireless&utm_campaign=webcasts-search-results-feed)

:::

## Introduction to Open RAN

### Quick Summary

#### I. Disaggregation of The Core Network
Disaggregation of the core network was started by 3GPP. It refers to the completion separation between control and user plane separation(CUPS) of EPC nodes in 3GPP release-14. CUPS provides the architecture enhancements for the separation of functionality and enable flexible network deployment an operation by distributed or centralized deployment and the independent scaling between control plane and user plane functions.
Accordingly, 5G Core (5GC) continues this with the Service Based Architecture (SBA) which leverages interactions between different network functions, aligning system operations with the Network Functions Virtualization (NFV) and Software Defined Networking (SDN) paradigms. In this part, NFV created the possiblities to enable moving of hardware into software that give a greater impact to the future. For instance, you need a MP3 hardware to listen a music in past few decades. Now, you can listen a music easily via an application through a smartphone.

#### II. Introducing to Open RAN
Open Radio Access Network (O-RAN) is interoperability of open hardware, software, and interfaces for cellular wireless networks. With this technology, it can reduce the dependency for a single vendor and flexibility to enhance radio access components from multiple vendors. Open RAN does not mean open sources system but it is open interfaces. It slightly different means with open source. This picture below explains the implementation of networks with Open RAN.


#### III RAN Evolution

Notes:
TMA (Tower Mounted Amplifier)
RF Cabling (Coaxial cable)
RU (Radio Unit)
BBU(Baseband Unit)




**Comparison Table**


#### IV. Architecture of Open RAN

- D-RAN architecture, the whole base station is located at the cell tower site. The RRUs are located at the top of the tower next to the antennas and the BBUs are located in an equipment room not too far from the tower itself. The RRUs and BBUs are directly connected via CPRI or Common Public Radio Interface, meaning that for every one RRU there will be one BBU connected to process the data.
- Centralized(C-RAN) architecture, the base station is split up. The RRUs stays at the cell site, while the BBUs are aggregated into a centralized office, sometimes called a BBU hotel, with a centralized controller to process calculations digitally
- Cloud RAN (C-RAN) architecture, it just quite different from C-RAN architecture. in previous explanation, The RRUs stays at the cell site, while the BBUs are aggregated into a BBU hotel, here the BBU hotel is moving in to the cloud that called a virtual baseband.

#### V. White Box RAN
There are few vendors deisgning all-in-one GPP based base station called *White Box RAN*. Instead of separate RRU and BBU, it's combine in a one box.


#### VI. ORAN -Alliance


One of leading grups in Open RAN movement is O-RAN Alliance. It was formed because two major organization was merged. They have two highest level goals, Openess and Intelligence. Openess will bring service agility and cloud scale economics. Open interfaces will enable small vendors and operator to introduce their own service. On the other hand, intellegence is networks self-driving ability using deep learning technique to embed intellegence in every layer of the RAN architecture.

Source https://www.youtube.com/watch?v=klV1PSGjPmM