TIdTelnetNegotiateEvent is an event type used to signal option negotiation features as describe in the TELNET protocol specifications. TELNET negotiated options allow a TELNET server to provide services that enhance the basic features available in a Network Virtual Terminal (NVT). Negotiated options utilize the "DO, DON'T, WILL, WON'T" conversation mechanism that allows either party (or both) to initiate an option request,
accept or request an option request, and implement the requested option.
AThread is the peer thread generating the option negotiation event.
TIdTelnetServer uses the OnNegotiate event handler to respond to TIdTelnetNegotiateEvent event notifications for connections.