Re: Basic question 1 - Traffic

[Ariel Millennium Thornton <arielmt at thornton2 dot com>]

Hello, Mr. Tanner.

Cygwin/X uses the X11 server for all GUI displays.  X11 is a
network-aware display server and uses network connections for all
communication between the display/input devices and the client
applications.  This is what allows a GUI program running on one PC to
take all of its input from and display all of its output to another PC.

It's no different when both the GUI and programs are running on the same
PC.  X11 just opens a network connection to itself using the loopback
interface (lo on most systems), and that's what ZA and other Windows
firewall programs trip on.

Basically, everything X11-related should be allowed not only to connect
to 127.0.0.1 without restrictions, they should also be allowed to act as
servers listening on 127.0.0.1.  Without that, Cygwin/X will be degraded
at best, and unable to work at all at worst.

-ArielMT


On Tue, 27 Sep 2005 06:30:30 +0100 Herbert Eppel wrote:

> On 27.09.2005 06:18 UK Time, Jack Tanner wrote:
> > Herbert Eppel wrote:
> > 
> >> No doubt this is a very basic question, and I'm not sure whether it
> >is  > really a question for this group or whether I should direct it
> >to the  > authors and/or user group of the ESP-r software, but I
> >wonder whether  > someone could shed some light on why Cygwin/X (or
> >perhaps it is just  > the individual components of the ESP-r software
> >I am running?)  > triggers ZoneAlarm access permission alerts and
> >generates constant  > internet traffic (or perhaps only 'trusted
> >zone' traffic?) as  > indicated by ZoneAlarm?
> > 
> > 
> > Chances are that you're seeing Cygwin/X connect to itself via TCP.
> > This  is normal.
> 
> Hi Jack,
> 
> thanks for your reply. I don't really understand why Cygwin/X needs to
> 
> connect to itself, but it seems a likely explanation for the traffic I
> 
> am seeing.
> 
> > 
> > Furthermore, Zone Alarm is a source of problems for many Cygwin/X
> > users.  The two are known to conflict. See 
> > http://x.cygwin.com/docs/faq/cygwin-x-faq.html.
> 
> I don't actually have a problem with ZoneAlarm, I was just curious
> about  why the various components of the ESP-r software I am using
> (and indeed  some external ones that came bundled with that software,
> for example  xv.exe) triggered a one-off ZoneAlarm access permission
> alert when they  were launched for the first time (they are now listed
> in ZoneAlarm's  list of programs). Can you offer further enlightenment
> here, or would  the ESP-r user list a more appropriate forum for this
> question?
> 
> Thank you.
> 
> Herbert Eppel
> -- 
> www.HETranslation.co.uk
> 
> 
> 
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-- 
"The most humbling achievement of the past millennium, I believe, is the
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-Ariel Millennium Thornton, Spokesman and Mascot, Thornton 2 Productions

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