SSH Tunnel - How does it works?

From: Pablo Hauser (pablohauser_at_yahoo.com.ar)
Date: 09/20/05

  • Next message: Chris Clymer: "Re: sftp question" 
    Date: Mon, 19 Sep 2005 23:33:21 +0000 (GMT)
To: secureshell@securityfocus.com

    Hi list,
            Using SSH Tunneling, I was wondering how does
    it really works in the following scenario:

    Host1 running putty with tunneling on port xx, and
    redirecting its traffic to Host2, and Host3 accessing
    host 1 via port xx.

      | Host3 | | Host1 | | Host2 |
      | traffic: | --> |SSH tun on xx| --> | receipt: |
      |(Host1:xx)| |redir. Host2 | |(Host1:xx)|

    The idea is that Host1 redirects Host3:xx to Host2,
    but the question is: When traffic from Host2 comes
    back to Host1 as a reply of the former packet, how
    does Host1 REALLY knows that the packet must be
    forwarded to the tunnel and not, for example, to its
    Default Gateway?

    I think it should add some kind of dynamic route for
    that single connection, or keep some kind of table to
    'know' that the answer should be lead to the tunnel,
    but those are only suppositions... Maybe any of you
    have the correct answer.

    Thanks in advance.

    Pablo D. Hauser | pH
    www.securearg.net | Secure from the source

            

            
                    
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  • Next message: Chris Clymer: "Re: sftp question"

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