Connection protocol channel request names

PuTTY

F.1 Connection protocol channel request names

These names can be sent in a SSH_MSG_CHANNEL_REQUEST message.

[email protected]
This is sent by a client to announce that it will not have more than one channel open at a time in the current connection (that one being the one the request is sent on). The intention is that the server, knowing this, can set the window on that one channel to something very large, and leave flow control to TCP. There is no message-specific data.
[email protected]
PuTTY sends this request along with some SSH_MSG_CHANNEL_WINDOW_ADJUST messages as part of its window-size tuning. It can be sent on any type of channel. There is no message-specific data. Servers MUST treat it as an unrecognised request and respond with SSH_MSG_CHANNEL_FAILURE.

(Some SSH servers get confused by this message, so there is a bug-compatibility mode for disabling it. See section 4.27.5.)