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TELNET OUTPUT HORIZONTAL TABSTOPS OPTION RFC 653, NIC 31156 (Oct. 25, 1974) D. Crocker (UCLA-NMC) Online file: [ISI]<DCROCKER>NAOHTS.TXT

             TELNET OUTPUT HORIZONTAL TABSTOPS OPTION

1. Command name and code

 NAOHTS 11 (Negotiate About Output Horizontal Tabstops)

2. Command meanings

 In the following, we are discussing a simplex connection, as described in 
 the NAOL and NAOP Telnet options.
    IAC DO NAOHTS 
       The data sender requests or agrees to negotiate about output 
       horizontal tabstops with the data receiver.  In the case where 
       agreement has been reached and in the absence of further 
       subnegotiations, the data receiver is assumed to be handling output 
       horizontal tabstops.
    IAC DON'T NAOHTS 
       The data sender refuses to negotiate about output horizontal tabstops 
       with the data receiver, or demands a return to the unnegotiated 
       default mode.
    IAC WILL NAOHTS 
       The data receiver requests or agrees to negotiate about output 
       horizontal tabstops with the sender.  In the case where agreement has 
       been reached and in the absence of further subnegotiations, the data 
       receiver alone is assumed to be handling output horizontal tabstops.
    IAC WON'T NAOHTS 
       The data receiver refuses to negotiate about output horizontal 
       tabstops, or demands a return to the unnegotiated default mode. 
    IAC SB NAOHTS DS <8-bit value> ... <8-bit value> IAC SE
       The data sender specifies, with the 8-bit value(s), which party should
       handle output horizontal tabstop considerations and what the stops 
       should be.  The code for DS is 1.
    IAC SB NAOHTS DR <8-bit value> ... <8-bit value> IAC SE
       The data receiver specifies, with the 8-bit value(s), which party 
       should handle output horizontal tabstop considerations and what the 
       stops should be.  The code for DR is 0.

3. Default

 DON'T NAOHTS/WON'T NAOHTS.
    In the default absence of negotiations concerning which party, data 
    sender or data receiver, is handling output horizontal tabstops, neither 
    party is required to handle them and neither party is prohibited from 
    handling them; but it is appropriate if at least the data receiver 
    handles horizontal tabstops, albeit primitively.

4. Motivation for the Option

 Please refer to section 4 of the NAOL and of the NAOP Telnet option 
 descriptions.

 5. Description of the Option

 The data sender and the data receiver use the 8-bit value(s) along with the 
 DS and DR SB subcommands as follows (multiple 8-bit values are allowed only 
 if each is greater than zero and less than 251):

    8-bit value :                     Meaning :

    0            Command sender suggests that he alone will handle  
                 tabstops, for the connection.                      
    1 to 250     Command sender suggests that the other party alone 
                 should handle tabstop considerations, but suggests 
                 that the indicated value(s) be used. The value(s)  
                 are the column numbers, relative to the physical   
                 left side of the printer page or terminal screen,  
                 that are to be set.                                
    251 to 254   Not allowed, in order to be compatible with        
                 related Telnet options. 
    255          Command sender suggests that the other party alone 
                 should handle output tabstops and suggests nothing 
                 about how it should be done. 

 The guiding rules are that:
    (1) if neither data receiver nor data sender wants to handle output 
    horizontal tabstops, the data receiver must do it, and
    (2) if both data receiver and data sender want to handle output 
    horizontal tabstops, the data sender gets to do it.
 The reasoning for the former rule is that if neither wants to do it, then 
 the default in the NAOHTS option dominates. If both want to do it, the 
 sender, who is presumed to have special knowledge about the data, should be 
 allowed to do it, taking into account any suggestions the receiver may make.
 As with all option negotiations, neither party should suggest a state 
 already in effect except to refuse to negotiate; changes should be 
 acknowledged; and once refused, an option should not be resuggested until 
 "something changes" (e.g., another process starts).
 At any time, either party can disable further negotiation by giving the 
 appropriate WON'T NAOHTS or DON'T NAOHTS command.