[CentOS] ssh -X versus -Y

Sun Jul 5 19:23:39 UTC 2015
Gordon Messmer <gordon.messmer at gmail.com>

On 07/05/2015 04:51 AM, Liam O'Toole wrote:
> One practical difference I have seen is the improved performance of -Y
> over -X. I have long attributed that to the relaxation of security
> controls in the former case.

When and how did you measure that?

The -Y change was introduced in Fedora Core 3, in November 2004.  The 
default was changed to ForwardX11Trusted=yes just a month or two later. 
  I'm not sure -X and -Y ever behaved differently on Enterprise Linux or 

At this point, I don't think it's even possible to set 
ForwardX11Trusted=no any more.  The X SECURITY extension was replaced 
with "X Access Control Extension" several years ago.