12.2 Telnet Protocol Commands

The IAC (Interpret As Command) character’s decimal value is 255 (FF in the hexadecimal notation) and is of special significance. If a character of this value is to be transmitted, it must be doubled. The IAC character is interpreted as the beginning of a Telnet protocol command.

This means the IAC character may be followed by the commands listed in the following table:

Command			Significance
Decimal Notation	Hexadecimal Notation	Symbol
236	EC	EOF	End of file
237	ED	SUSP	Suspend process
238	EE	ABORT	Abort process
239	EF	EOR	End of record
240	F0	SE	Sub option end
241	F1	NOP	No operation
242	F2	DM	Data mark (usually mark urgent data in TCP segment)
243	F3	BRK	Break process
244	F4	IP	Interrupt process
245	F5	AO	Abort output
246	F6	AYT	Are your there?

Command			Significance
Decimal Notation	Hexadecimal Notation	Symbol
247	F7	EC	Escape character (escape to the command...