Traversing TCP

This prototype introduce a new technic for firewall traversing. It has been designed by Vincent Neri and Tangui Morlier in collaboration with Ala Rezmerita (she has now integrated this prototype in her PVC, greatly improved and secured the mecanism and combined it with other traversing technics. Check out her web site for more details).

If two peers are behind a firewall, they cannot communicate directly. TTCP allows, by reenacting TCP SYN packets, to establish connection despite such network configuration. A third part element, the broker, helps the peers during the establishment of the connection. Once established, the communication is direct and the broker is no more needed.


You can download the source code of our prototype here. To compile it on Linux or MacOs, you need to install libnet and libpcap (debian packages: libnet-dev and libpcap-dev).

The source is distributed under both GPL and CeCCIL licences. If you want to modify the source code, feel free to choose one of these.

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