Am 16.02.2003 00:17:02, schrieb "panamerica334 at uni.de" <panamerica334 at 
uni.de>:

[snip]
>after pressing CR:
>
>  Proto  Lokale Adresse         Remote-Adresse            Status
>  TCP    0.0.0.0:1026           0.0.0.0:0              LISTENING
>  TCP    0.0.0.0:10000          0.0.0.0:0              LISTENING
>  TCP    127.0.0.1:1026         127.0.0.1:10000        ESTABLISHED
>  TCP    127.0.0.1:10000        127.0.0.1:1026         ESTABLISHED
>
>so here the temporary port is 1026, but THIS time it's listening, too!!
>
>---~~---
>
>conclusion:
>
>- either windows netstat displays an established connection twice, one time 
>connected and one time listening (although it is not listening),
>- or my firewall-display-all-connections-tool is filtering the listening 
>temporary port away.
>
>sorry, i only have these two programs to display network connections :/

Tuomas Lukinmaa wrote an eMail to devl at freenetproject.org with the subject
"Re: [freenet-dev] Current IPv4 address "NOT AVAILABLE"" on Tue, 04 Mar 2003 
19:10:54 +0200

He included this interesting URL: 
http://www.hsc.fr/ressources/breves/min_srv_res_win.en.html

I quote now text related to the open ports problem under Windows:
~~~~~~~~~~~~~~~~~~~~ start quote ~~~~~~~~~~~~~~~~~~~~ 
_Warning_:

The netstat command does not exactly report TCP and UDP ports states. Instead,
it reports state of TDI transport addresses and connection endpoints, whereas
only TDI connection endpoints represent TCP or UDP sockets.

In particular, when a Windows system establishes an outgoing TCP connection
(active open), the local port used as source is reported as in the LISTENING
state.

In the following example, the local system has established a TCP connection from
source port 1367 to destination port 22 of a remote system.

The netstat command output, filtered to show only lines containing port number
1367 is:

C:\WINDOWS>netstat -anp tcp | find ":1367"
  TCP    0.0.0.0:1367           0.0.0.0:0              LISTENING
  TCP    192.70.106.142:1367    192.70.106.76:22       ESTABLISHED

The second line shows the established connection, from local port 1367 to remote
port 22. However, the first line is incorrect because it reports local port 1367
in the LISTENING state, whereas no TCP server is available on this port.

Thus, for each outgoing TCP connection, an additional line will appear in
netstat output, showing a TCP port in LISTENING state. It is important to make
the difference between an opened TCP port and one incorrectly reported by 
netstat
in the LISTENING state.

Note: this bug has been fixed in recent builds of Windows .NET Server, starting
with build 3606.
~~~~~~~~~~~~~~~~~~~~ end of quote ~~~~~~~~~~~~~~~~~~~~ 

That means it's not a JVM problem, it's a Windows netstat problem!

>
>---~~---
>
>system:
>
>java version "1.4.0_01"
>Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0_01-b03)
>Java HotSpot(TM) Client VM (build 1.4.0_01-b03, mixed mode)
>
>windows 98se, winsock 2.2

I use Win2k, see the same bug in netstat. I don't know which versions
of Windows include a buggy netstat.


Greetings,
Stef



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