TN3270 Server Manual

Introduction to the Guardian TN3270 Server
TN3270 Server Manual—424097-001
1-3
Option Negotiation
Option Negotiation
Guardian TN3270 Server expects the negotiation sequence shown in Figure 1-1.
In Figure 1-1, term-model is one of the supported terminal model names listed in
Section A, Terminal Models.
During Guardian TN3270 Server option negotiation, the following rules apply:
•
The order in which WILL and DO commands for a specific option are exchanged
does not matter.
•
The Guardian TN3270 Server responds with a WONT option if it receives a DO
option for any Telnet option other than BINARY or EOR.
•
The client must accept a DO TTYPE command by sending a WILL TTYPE
response, and it must send WILL and DO commands for both EOR and BINARY
options.
For details on Telnet option negotiation, refer to RFC 854 and RFC 855. For information
on RFC 854 and RFC 855, see Related Manuals
on page xi.
TN3270 Protocol Restrictions
Due to limitations of the public-domain TN3270 protocol, the following 3270 terminal
features are not supported:
•
SYSREQ key
•
ATTN key
•
Negative terminal responses
•
PTR (printer) protocol
Figure 1-1. Option Negotiation Sequence
002CDT .CDD
Guardian
TN3270 Server Client
DO TTYPE WILL TTYPE
SEND TTYPE
TTYPE IS term-model
WILL, DO BINARY WILL, DO BINARY
WILL, DO EOR WILL, DO EOR
3270 DATA