Decoding WebRTC Architectures: P2P, SFU, and MCU Simplified
Tags: webrtc, p2p, sfu, mcu
Published: 2023-09-25 16:55:13

In this piece, we will break down the intricacies of WebRTC architecture into easily digestible chunks.

[WebRTC ](https://www.digitalsamba.com/blog/comparing-webrtc-with-other-real-time-communication-protocols)is an open-source framework that enables real-time communication via peer-to-peer web applications. Whether you've participated in a browser-based video conference or engaged in a real-time online game, the odds are high that WebRTC played a role in powering that experience.

## The Foundation of Video Conferencing Architectures
Central to any video conferencing solution is the architectural approach to transmitting audio and video streams between participants. For instance, with N participants, each person needs to view and hear the streams from the remaining N-1 attendees. There are chiefly three models used to achieve this:

- [P2P](https://www.digitalsamba.com/blog/peer-to-peer-video-conferencing-for-developers) (Peer-to-Peer or Mesh)
- SFU (Selective Forwarding Unit)
- MCU (Multipoint Control Unit)

Moreover, a hybrid configuration is also possible, which adapts the architecture based on the participant count. We'll discuss this optimization tactic later in the article.

### The P2P Paradigm
P2P, or peer-to-peer, is the most fundamental form of architecture. In a P2P setup, each conference attendee directly connects with every other participant to share their audio and video.

**Advantages:**

- Privacy is inherently strong since no intermediary servers are involved, facilitating end-to-end encryption.
- Operational costs and complexity are minimal due to the absence of any intermediary servers.

**Drawbacks:**

- Inefficient use of upload bandwidth.
- Elevated CPU usage on user devices, particularly during multiple peer connections.
Generally, P2P architecture is deemed ideal for one-on-one interactions rather than larger meetings.

### Exploring SFU Architecture
SFU has become the architecture of choice in modern video conferencing solutions. In an SFU configuration, centralized media servers receive and route media streams without altering them.

**Advantages:**

- Efficient use of upload bandwidth as each participant sends their stream only once to the SFU server.
- Enhanced scalability and adaptive streaming through techniques like Simulcast.

**Drawbacks:**

- The requirement of intermediate media servers increases operational costs and complexity.
- Full end-to-end encryption isn’t native to the architecture but can be achieved with custom solutions.

### The MCU Model
The MCU architecture combines the audio and video streams from all participants into a single composite stream. Each participant then receives this unified stream.

**Advantages:**

- Highly efficient in terms of CPU and bandwidth usage on the client side.
- Simplifies the frontend architecture as only one stream needs to be managed.

**Drawbacks:**

- Fixed layout controlled by the central server, offering less flexibility to users.
- Server-side complexity and resource usage are high, making it a cost-intensive solution.

#### Hybrid Approaches
In a hybrid setup, the architecture switches between P2P and SFU based on the number of participants. This can result in server resource savings, especially useful given that a significant portion of calls are often one-on-one.

**Advantages:**

- Maximizes the benefits of each architecture based on the context.

**Drawbacks:**

- Increased code complexity and maintenance demands, particularly when transitioning between architectures.

## Digital Samba: A WebRTC Powerhouse
Digital Samba is a frontrunner in delivering GDPR-compliant video conferencing API and SDK solutions. Our platform is WebRTC-driven, ensuring high-quality, real-time video interactions.

Our offering is versatile and can adapt between P2P and SFU architectures to provide the most efficient and cost-effective video conferencing experience. With additional [features](https://www.digitalsamba.com/features) like screen sharing, file sharing, and interactive whiteboards, Digital Samba stands as a comprehensive solution for real-time communication needs.

[Contact our sales team](https://www.digitalsamba.com/contact-sales) today to explore how Digital Samba can elevate your video conferencing solutions.

Do you wanna know more? Read the full article [here](https://www.digitalsamba.com/blog/p2p-sfu-and-mcu-webrtc-architectures-explained)