ช่องทางข้อมูลที่เชื่อถือได้และไม่เชื่อถือได้

You can already send and receive data over an RTCDataChannel. Now you will tune its behavior. Unlike a fixed protocol, data channels let you choose between reliable and unreliable delivery, just like TCP versus UDP.

By default a data channel is reliable and ordered: every message arrives, in the sequence it was sent. This is perfect for chat or file transfer where correctness matters most.

Data channels run over SCTP, a protocol that supports both reliable and partially reliable modes. This flexibility is why you can trade reliability for lower latency.

Set ordered: false to let messages arrive in any order. Useful when each message is independent and waiting for order would add delay.

Use maxRetransmits to cap how many times a lost message is resent. Setting it to 0 means fire-and-forget, ideal for fast-changing game state.

Alternatively, maxPacketLifeTime retries a message only for a set number of milliseconds, then gives up. Use this instead of (not together with) maxRetransmits.

Match the mode to the use case:

• Reliable ordered: chat, files, commands
• Unordered, no retransmit: player positions, sensor data
• Time-limited: data only useful briefly

Channels can carry binary as ArrayBuffer or typed arrays, not just strings. Set binaryType on the receiver to control how it is delivered.

Sending too fast fills the outgoing buffer. Check bufferedAmount and pause when it grows beyond a threshold to avoid overwhelming the connection.

Listen for bufferedamountlow to resume sending once the buffer drains, creating a smooth flow-controlled pipeline.

Configure reliability and ordering to fit your data, use binary types for efficiency, and respect backpressure so the channel stays responsive. These choices make data channels powerful for games, file sharing, and live collaboration.

You learned to configure data channel reliability:

• Reliable ordered by default, over SCTP
• ordered:false, maxRetransmits, and maxPacketLifeTime trade reliability for latency
• Binary data via binaryType
• Backpressure with bufferedAmount and bufferedamountlow

Tune each channel to its data's needs.