files/en-us/web/api/webtransport/reliability/index.md
{{APIRef("WebTransport API")}}{{SecureContext_Header}} {{AvailableInWorkers}}
The reliability read-only property of the {{domxref("WebTransport")}} interface indicates whether the connection supports reliable transports only, or whether it also supports unreliable transports (such as UDP).
A string with one of the following values:
pending
reliable-only
supports-unreliable
const url = "https://example.com:4999/wt";
async function initTransport(url) {
// Initialize transport connection
const transport = new WebTransport(url);
// Once ready fulfils the connection can be used
// Prior to this the reliability is "pending"
await transport.ready;
if (transport.reliability === "reliable-only") {
// Use connection only with reliable transports
} else {
// Use connection with either reliable or unreliable transports.
}
// …
}
{{Specifications}}
{{Compat}}