Security Incidents: Re: Is it possible to derease gradually the number of Client port (add up time table) ?

[Ben Timby <asp () webexc com>]

The incrementing of port numbers is done by the host OS IP stack. This 
is done when a client connection is opened without providing a local 
port number. The next available port number is used. I would imagine the 
IP stack could just as easily decrement the port number to find the next 
unused port, although I don't know of any stacks that do this. However, 
TCP client software can of course request a local port number to connect 
FROM (ala hping, netcat, etc), so a scanner or other program could do 
the same.
I would imagine that incrementing port numbers is an artifact of 
reference IP stack implementation. Someone, please let me know if my 
assumptions are incorrect!
Todd Jang wrote:

> I add up time table below logs which are blocked.
> I dimly remember. someone said the reason decreased port number may be a specific of O.S
> or application's logic operated in client.
> Is there any reason Why The port number always has to increase ? 

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