What does “258EAFA5-E914-47DA-95CA-C5AB0DC85B11” means in WebSocket Protocol May 25, 2023 by Tarik The RFC explains it. It is a GUID, selected because it is “unlikely to be used by network endpoints that do not understand the WebSocket Protocol”. See RFC 6455. If you’re interested in the specifics of the format for GUIDs like that, see RFC 4122.
