Subject: Subsystems.

From: Bill Sommerfeld <[email-masked]>
Date: Sun, 28 Jan 2001 23:39:29 -0500

<working group chair hat on>

The apparent consensus of the working group is that subsystems, not
channels, should be used for "large scale" extensions along the lines
of sftp.  

The exact means by which a secure shell server starts an instance of a
particular subsystem is purely a local implementation / quality of
implementation issue, out of scope for the working group.

Server implementors should ensure that whatever means they use to
start subsystems is robust; however, exactly how they do this is a
local matter.

As the subsystem interface is intended to be "pluggable", it's always
possible that misconfiguration on the part of the administrator or end
user may cause a requested subsystem to fail to start correctly.

					- Bill

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From: [email-masked] (Niels M�ller)
Date: 29 Jan 2001 14:55:04 +0100

> channels, should be used for "large scale" extensions along the lines

I'm not sure I understand this paragraph. But I don't quite agree with
it. For instance, I believe that a file transfer service which uses
one channel for each open file would be a useful and natural way to
take advantage of the channel mechanism, even if sftp happens to do
things differently.

I agree fully with your other paragraphs.

Regards,
/Niels