Unexpected network-traffic

Unexpected network-traffic

[Christian Göbel]

Hello,
when I start the X via my personal Firewall
asks me several permissions for access to the Internet:
xterm.exe       Destination IP:127.0.0.1:Port 6000
XWin.exe        Destination IP: 130.104.1.1: DNS
XWin.exe        Source IP: 0.0.0.:Port 6000

Whatever I type in xterm within X my network-monitor shows me
extensive nettwork traffic (outgoing and ingoing) after every
single letter I type.
Is this something to worry about?

Can anybody explain me why the use of  Cygwin-XFree86 causes
network traffic whatever I type in xterm? Are there any security issues?

Cygwing 1.5.5 on Win2000pro

Thanks a lot
Christian

Re: Unexpected network-traffic

[Alexander Gottwald]

On Wed, 19 Nov 2003, Christian Göbel wrote:

> Whatever I type in xterm within X my network-monitor shows me
> extensive nettwork traffic (outgoing and ingoing) after every
> single letter I type.
> Is this something to worry about?
> 
> Can anybody explain me why the use of  Cygwin-XFree86 causes
> network traffic whatever I type in xterm? Are there any security issues?

X11 uses TCP as transportprotocol and therefore causes network traffic.

bye
	ago
-- 
 Alexander.Gottwald@s1999.tu-chemnitz.de 
 http://www.gotti.org           ICQ: 126018723

Re: Unexpected network-traffic

[Alexander Gottwald]

On Thu, 20 Nov 2003, Christian Göbel wrote:

> What I expect is that X11 causes network traffic when I am connected to a
> X-server somewhere over a network - but why it causes network traffic without
> beeing connected to another computer?
> Is there any (perhaps technical) explanation for that?

Yes. X11 can be used over TCP and over Unix Domain Sockets. Unix Domain Sockets
is emulated in cygwin with TCP. So X11 in cygwin does always use TCP. 

You might have noticed that xterm connects to a 127.0.0.0 address which is a
local only address. The xserver connects to IN_ADDR_ANY and not to a specific 
network interface. 

All network traffic (except the DNS query) is only local.

bye
	ago
-- 
 Alexander.Gottwald@s1999.tu-chemnitz.de 
 http://www.gotti.org           ICQ: 126018723