Wireshark is a network protocol analyzer, which lets you see what’s happening on your network at a microscopic level. It can be used to examine security problems, troubleshoot network issues, verify network applications, and debug protocol implementations... (
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The program works with the following extensions:
cap,
fdc,
rf5,
syc,
tpc,
tr1,
erf,
acp,
wpc,
trc,
wpz,
pkt,
enc,
5vw,
apc,
atc,
bfr,
pcap,
snoop and
trace