hi people , my question is simple : if i use some packet injection library like libnet to send a packet from host A to host B , and libpcap to capture packets and monitor all network traffik. let's say i send TCP SYN packet (like if my host is establishing a TCP connection with host B ), the host may answer with a SYN packet accepting my connection , then two possibilities : 1 - the kernel will send RST packet to the host B coz the SYN packet from host B be is assimilated as connection establishment request to a non existant service. 2 - the libpcap tool im using acts as a service and the kernel just deliver the SYN packet from B to my sniffing tool without taking any action like in 1. in case 1 the kernel will generate an extra trafic i dont need . in case 2 it acts transparently. i think that case 2 is more correct , but i'm not sure. Any comments greatly appreciated. Regards. -- Saber Zrelli kanazawa university international house kakuma-machi , kanazawa , Ishikawa 920-1192 Japan.