On Jan 5, 2008 11:49 PM, Luke -Jr <luke@dashjr.org> wrote:
> Any protocol that uses TCP and human-readable text "supports" the *telnet*
> * client*.  That's the way most of the Internet got designed.  When you're
> testing a server, you telnet to it and converse via the protocol you're
> trying to implement.  Once you get the server running, you can implement a
> client that talks to it.

Which telnet client? While it may often work in practice, how many non-telnet
protocols allow for Telnet features like AYT, or feature negotiation?


Pretty much any telnet client.  AYT is one of the codes in the range F0-FF, (and is only to be interpreted as such if immediately preceded by FF) which won't be used by 7-bit ASCII.  That's what most Internet protocols have traditionally used, and even UTF-8 won't use FF.

These protocols were designed by people who wanted to minimize the chance that legitimate data would have to be "escaped", and designed them to not conflict with one another.