Can we disable SSH compression by default?

Mark D. Baushke mdb at
Sun Feb 17 05:41:37 AEDT 2019

Hi Yegor,

The OpenSSH sources already disable SSH compression by default.

Look in myproposal.h for how KEX_DEFAULT_COMP is defined.

#define	KEX_DEFAULT_COMP "none,zlib at"

Looking at a verbose connection:
  The client sends to the server "none,zlib at,zlib"
  The server sends to the client "none,zlib at,zlib"

The sshconnect2.c ammends the conversation to update the default based
on the 'compression' option ('ssh -C' or 'ssh -oCompression=yes' or in
the config file).

	-- Mark

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