101 Switching Protocols
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
- 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