Security Incidents mailing list archives
Re: Is it possible to derease gradually the number of Client port (add up time table) ?
From: Ben Timby <asp () webexc com>
Date: Wed, 10 Mar 2004 15:33:57 -0500
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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Current thread:
- Is it possible to derease gradually the number of Client port ? toddjang (Mar 09)
- RE: Is it possible to derease gradually the number of Client port ? Rob Shein (Mar 09)
- RE: Is it possible to derease gradually the number of Client port (add up time table) ? Todd Jang (Mar 10)
- RE: Is it possible to derease gradually the number of Client port (add up time table) ? Rob Shein (Mar 10)
- Re: Is it possible to derease gradually the number of Client port (add up time table) ? Lionel Ferette (Mar 10)
- Re: Is it possible to derease gradually the number of Client port (add up time table) ? Frank Knobbe (Mar 11)
- Re: Is it possible to derease gradually the number of Client port (add up time table) ? Ben Timby (Mar 11)
- RE: Is it possible to derease gradually the number of Client port (add up time table) ? Todd Jang (Mar 10)
- RE: Is it possible to derease gradually the number of Client port ? Rob Shein (Mar 09)