networking - Why do I see packets that where source and destination are not my IP address -


im new networking world , i'm trying use wireshark hang of how packets sent machine etc. hence question might dumb one.

when open wireshark packet analyzer gui (on windows 7) there source , destination column. shows packets source ip not mine , destination ip not mine either. why happening? network interface card should receiving , sending packets addressed to/sent ip address, right? (attaching screenshot. ip address 10.177.255.186)

wireshark screenshot

thanks.

on small lan packets broadcast everyone. broadcast mean data physically sent everyone. when received network interface determines if packet sent looking @ address.

using wireshark network interface can set promiscuous mode means packets captured , sent network interface cpu. allows programs wireshark record packets , not ones addressed computer.

edit: packets don't have sent computers. hub can used connect multiple computers , acts repeater meaning packets sent everywhere (except on wire packet came from). switch similar smarter. if 3 computers a, b , c connected switch , sends packet b packet first arrive @ switch. if switch knows wire b connected send down wire. if doesn't know sends everywhere , later if b replies switch figure out wire b on. means c never see of messages sent between , b once switch knows wires , b on.


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