2002-06-09 22:17:03 +00:00
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tcptraceroute is a traceroute implementation using TCP packets.
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2002-03-22 03:31:49 +00:00
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2002-06-09 22:17:03 +00:00
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The more traditional traceroute(8) sends out either UDP or ICMP ECHO
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packets with a TTL of one, and increments the TTL until the destination
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has been reached. By printing the gateways that generate ICMP time
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exceeded messages along the way, it is able to determine the path
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packets are taking to reach the destination.
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2002-03-22 03:31:49 +00:00
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2002-06-09 22:17:03 +00:00
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The problem is that with the widespread use of firewalls on the modern
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Internet, many of the packets that traceroute(8) sends out end up being
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filtered, making it impossible to completely trace the path to the
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destination. However, in many cases, these firewalls will permit inbound
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TCP packets to specific ports that hosts sitting behind the firewall are
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listening for connections on. By sending out TCP SYN packets instead of
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UDP or ICMP ECHO packets, tcptraceroute is able to bypass the most
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common firewall filters.
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2002-03-22 03:31:49 +00:00
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WWW: http://michael.toren.net/code/tcptraceroute/
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2002-06-09 22:17:03 +00:00
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- Simon 'corecode' Schubert
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