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Appendix F: SSH-2 names specified for PuTTY

There are various parts of the SSH-2 protocol where things are specified using a textual name. Names ending in are reserved for allocation by the PuTTY team. Allocated names are documented here.

F.1 Connection protocol channel request names

These names can be sent in a SSH_MSG_CHANNEL_REQUEST message.
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.
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.)

F.2 Key exchange method names
These appeared in various drafts of what eventually became RFC 4432. They have been superseded by rsa1024-sha1 and rsa2048-sha256.

F.3 Encryption algorithm names
These were used in drafts of what eventually became RFC 4345. They have been superseded by arcfour128 and arcfour256.

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[PuTTY release 0.68]


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