Network Working Group				 Dave Crocker, Rand-ISD
Request for Comments: 729			 (Dcrocker at Rand-Unix)
NlC: 40306					 13 May l977




			TELNET Byte Macro Option


1. Command name and code:

   BM 19

2. Command Meanings:

   IAC WILL BM

	The sender of this  command REQUESTS or AGREES  to use the  BM
	option, and will send sing1e  data characters which are to  be
	interpreted as if longer data strings had been sent.

   IAC WON'T BM

	The  sender  of  this  option  REFUSES  to  send  single  data
	characters which  are  to be  interpreted  as if  longer  data
	strings had been sent.

   IAC DO BM

	The sender REQUESTS or AGREES to have the other side (send  of
	WILL BM) issue  send single  data characters which  are to  be
	interpreted as if longer data strings had been sent.

   IAC DON'T BM

	The sender REFUSES to allow the other side to send single data
	characters which  are  to be  interpreted  as if  longer  data
	strings had been sent.

   IAC SB BM   
                    IAC SE
	where:

	    is the  data byte actually  to be sent  across
	   the network; it may NOT be Telnet IAC (decimal 255).


RFC #729 Telnet Byte Macro Option				 Page 2



	    is a  one-byte binary number,  indicating how  many
	    characters follow, up to the ending  IAC
	   SE, but not including it.

	    is a string of one or more Telnet  ASCII
	   characters and/or commands,  which the  is  to
	   represent; any  character may  occur within  an  .

	The indicated    will  be  sent  instead  of  the
	indicated . The receiver of the 
	(the sender  of the  DO BM)  is to  behave EXACTLY  as if  the
	 of bytes had instead been received from the
	network. This  interpretation is  to  occur before  any  other
	Telnet interpretations, unless the  occurs as part
	of a BM subcommand; in this case no special interpretation  is
	to be made.

	Note that the effect of a particular  may be
	negated by reseting it to "expand" into itself.

	 is decimal 01.


   IAC SB BM   IAC SE

	The receiver  of the   for    accepts  the
	requested definition and will perform the indicating expansion
	whenever a   is received and is  not part of a  BM
	subcommand.

	 is decimal 02.


   IAC SB BM    IAC SE

	The receive  of  the   for    refuses  to
	perform  the  indicated  translation  from     to
	 either because the particular 
	is not  an acceptable  choice  or because  the length  of  the
	 exceeds available storage.

    is decimal 03.

    may be

	    which is decimal 01; or

	    which is decimal 02.


RFC #729 Telnet Byte Macro Option				 Page 3




   IAC SB BM   IAC SE

	The  is to be treated as real data, rather than as
	representative of the 

	 is decimal 03.




3. Default:

   WON'T BM -- DON'T BM

	No reinterpretation of data is allowed.

4. Motivation for the option:

   Subcommands for Telnet options currently require a minimum of  five
   characters to be sent over the network (i.e., IAC SB