Conceptual Task: - Architecture Design and Problem-Solving

1. Real-time Audio Synchronization

Objective: Ensure both singers hear the combined output in sync.

Solution:

• Use WebRTC: This library is ideal for real-time communication and provides low-latency audio streaming.
• Audio Mixing: Each client's audio stream is captured and sent to the server, which mixes the streams and sends the combined output back to both clients. This ensures synchronization.
• Synchronization Mechanism: Use timestamps or sequence numbers to align audio packets from both users.

2. Backend Integration

Objective: Determine the data exchanged between clients and the server.

Solution:

• Signaling Server: Handles the initial connection setup and coordinates the exchange of session descriptions and ICE candidates between peers.
• Media Server: Receives audio streams from both clients, mixes them, and sends the combined stream back to each client.

Data Flow:

1. Connection Setup:
   • User A and User B connect to the signaling server.
   • The server exchanges SDP (Session Description Protocol) offers/answers and ICE (Interactive Connectivity Establishment) candidates.
2. Audio Streaming:
   • Both clients send their audio streams to the media server.
   • The media server mixes the streams and sends the combined output back to each client.

3. Challenges and Solutions

Objective: Address technical challenges such as latency and echo.

Solution:

• Latency:
  • Buffering and Jitter Handling: Implement jitter buffers to handle variations in packet arrival times.
  • Adaptive Bitrate Streaming: Adjust the bitrate based on network conditions to reduce latency.
• Echo:
  • Echo Cancellation: Use WebRTC's built-in echo cancellation features.
  • Feedback Control: Implement mechanisms to prevent audio feedback loops.
• Synchronization:
  • Network Time Protocol (NTP): Use NTP to synchronize clocks across devices.
  • Timestamping: Timestamp audio packets to ensure proper sequencing.

Key Tools and Libraries

• WebRTC: For real-time audio streaming and peer-to-peer connections.
• Signaling Server: Custom implementation or use existing solutions like Socket.IO for signaling.
• Media Server: Use open-source solutions like Kurento or Janus for audio mixing and streaming.

Summary

Flow of Data:

1. Connection Setup: Users connect to the signaling server to establish a connection.
2. Audio Streaming: Audio streams are sent to the media server, mixed, and the combined output is sent back to users.

Tools and Libraries:

• WebRTC: Real-time audio streaming.
• Signaling Server: Manages connection setup.
• Media Server: Mixes and streams audio.