# Jonathan Notes #2

Main reference: [Introduction to OpenRAN](https://www.brighttalk.com/webcast/16515/359818?utm_source=brighttalk-portal&utm_medium=web&utm_content=Parallel%20Wireless&utm_campaign=webcasts-search-results-feed)
Deadline: 23th March 2020

###### tags: `ET6207701`

## Mobile Network

The celular network architecture consist of **Core Network** and **Access Network**.
The **Transport Network** are interfaces that connect the core network and the access netowork.
And the **Services** (ex. billing) are run above the Core networks.

Basicly, the the components that run the cellular network are machines that consist of hardware and/or software.
I try to describe it with this image
- The left part is the core network system (likely 3G). The core network is running using several devices that could be seen as a computer. for example the HLR/HSS is a database system containing user data.
- The right part is the access network. The configuration is distributed RAN, will be described later. The BBU in the image is a proprietary (design owned by the manufacturer) hardware with ASIC/FPGA computing device. The software that run on the ASIC/FPGA is also a proiprietary.

## Disaggregation of the Core Network
1. 3GPP Release 14, Introduce the **Control and User Plane Separation(CUPS)** architecture enhancements which disaggregate the network.

:::danger
**CUPS Architecture Advantages:**
1. Reducing Latency on application service by selecting the user plane nodes without effected by the number od control plane nodes
2. Supporting Increase of Data Traffic by add user plane nodes
3. Locating and Scaling the Control Plane and User Plane resources of the EPC nodes independently.
4. Independent evolution of the Control Plane and User Plane functions.
5. Enabling Software Defined Networking
:::

2. 5G increase this advantage by using the Service Based Architecture with SDN/NFV. SBA leverages service-based interaction between different network functions.
Network Fuction Virtualization played a big role, enable moving hardware functionalities into software.

## Disaggregation of the Access Network

### Distributed RAN:
1. Proprietary RRU
2. Proprietary Iterface
3. Proprietary BBU Hardware
4. Proprietary BBU Software
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The image above is a BBU. The BBU is placed in the access network part, it connects the radio unit to the core network.
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as tou can see in the image above. The BBU mainly consist of UMTP and LBBP, both are circuit boards that have several ICs such as Digital Signal Processing (DSP) and ASICs/FPGA chips. These chips (also the board) are propriatary and of course the software that run on it also proriatary.

### Virtualized RAN
1. Proprietary RRU
2. Proprietary Iterface
3. COTS BBU Hardware
4. Proprietary BBU Software
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The hardware that used for the vBBU is a normal server, it could be use x86-based (Intel/AMD) or ARM based servers (cavium for example).

### Open RAN
1. Open RRU (SDR)
2. Open Iterface
3. COTS BBU Hardware
4. Proprietary BBU Software, virtualized function
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Open RAN means any vendor can join the market.

## Types of Network Architecture
Based on the development of the virtualized RAN technology, engineers can deploy the network by several models.
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based on the image above, we can see the advantages of using virtualized RAN (Cloud RAN). in terms of deployment range. Also, less complex devices means easier to make and cheaper devices. its means network providers could deploy more base stations (densier) in dense area and save money for lesser dense area.
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The image above shows how SDN and NFV (Virtualized RAN) will used in 5G networks.

## O-RAN Architecture

## Why O-RAN

- Whitebox RAN = GPP based base-station = Whitebox RRU + COTS BBU
- Due to large volume, Economic of scale is achieveable. Cost is lower in high volume.
- Faster pace of innovation due to software-driven development.
- Vendors can't locks the system, more vendor choice
- Multiple vendor
- Reduced time to market
- Easier to scale up/down
- MNO (Network Operator) easier (and cheaper) to change the vendor.
- When some devices failed, it's more easier to MNO to change the devices.
- Easier/cheaper to manage since it's based on whitebox and SDR

## Cons
- Higher Energy (ASIC and FPGA is using less power)
- might be slower (ASIC and FPGA speed usually higher since it's specially designed)
- Durability might be a problem