RFC 1091 (rfc1091) - Page 2 of 7
Telnet terminal-type option
Alternative Format: Original Text Document
RFC 1091 Telnet Terminal-Type Option February 1989 IAC SB TERMINAL-TYPE SEND IAC SE Server requests client to transmit his (the client's) next terminal type, and switch emulation modes (if more than one terminal type is supported). The code for SEND is 1. (See below.) IAC SB TERMINAL-TYPE IS ... IAC SE Client is stating the name of his current (or only) terminal type. The code for IS is 0. (See below.) 3. Default WON'T TERMINAL-TYPE Terminal type information will not be exchanged. DON'T TERMINAL-TYPE Terminal type information will not be exchanged. 4. Motivation for the Option On most machines with bit-mapped displays (e.g., PCs and graphics workstations) a client terminal emulation program is used to simulate a conventional ASCII terminal. Most of these programs have multiple emulation modes, frequently with widely varying characteristics. Likewise, modern host system software and applications can deal with a variety of terminal types. What is needed is a means for the client to present a list of available terminal emulation modes to the server, from which the server can select the one it prefers (for arbitrary reasons). There is also need for a mechanism to change emulation modes during the course of a session, perhaps according to the needs of applications programs. Existing terminal-type passing mechanisms within Telnet were not designed with multiple emulation modes in mind. While multiple names are allowed, they are assumed to be synonyms. Emulation mode changes are not defined, and the list of modes can only be scanned once. This document defines a simple extension to the existing mechanisms, which meets both of the above criteria. It makes one assumption about the behaviour of implementations coded to the previous standard in order to obtain full backwards-compatibility. VanBokkelen
