Description

The HTTP 101 Switching Protocols response code indicates a protocol to which the server switches. The protocol is specified in the Upgrade request header received from a client.

The server includes in this response an Upgrade response header to indicate the protocol it switched to.

The process is described in the following article: Protocol upgrade mechanism

See Also

• Spec
• Upgrade, the header that triggers the protocol switch
• WebSockets, a protocol which can be used with this status code
• 426 Upgrade Required, a status code that can be used to notify the client to switch to a different protocol

Source: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/101