HTTP 101 Switching Protocols vs 425 Too Early
HTTP 101 (Switching Protocols) is a 1xx Informational response, while 425 (Too Early) is a 4xx Client Error response. 101 indicates that the server understands the Upgrade header field request and indicates which protocol it is switching to. In contrast, 425 means that the server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT).
Descripción
The server understands the Upgrade header field request and indicates which protocol it is switching to.
Cuándo lo verás
When upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
Cómo solucionarlo
This is normal behavior during protocol upgrades. Ensure your client supports the target protocol.
Descripción
The server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT).
Cuándo lo verás
When a server rejects a request sent as TLS 1.3 early data due to replay risk.
Cómo solucionarlo
Retry the request after the TLS handshake completes.
Diferencias clave
101 is a 1xx Informational response, while 425 is a 4xx Client Error response.
HTTP 101: The server understands the Upgrade header field request and indicates which protocol it is switching to.
HTTP 425: The server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT).
You encounter 101 when when upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
You encounter 425 when when a server rejects a request sent as TLS 1.3 early data due to replay risk.
Cuándo usar cada uno
For 101 (Switching Protocols): This is normal behavior during protocol upgrades. Ensure your client supports the target protocol. For 425 (Too Early): Retry the request after the TLS handshake completes.