Wireshark is a network packet analyzer, which presents captured packet data in as much detail as possible. It can be used to troubleshoot network problems, examine security problems, verify network applications, debug protocol implementations, and learn network protocol internals... (
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The program works with the following extensions:
apc,
atc,
bfr,
cap,
fdc,
rf5,
syc,
tpc,
tr1,
erf,
acp,
trc,
wpc,
pkt,
wpz,
enc,
5vw,
pcap,
snoop and
trace