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I am on a wifi network. I am using a wifi adapter to connect to a wifi hotspot. In the captured packets, I see a lot of packets to and from an unknown mac address. If I search the mac address's vendor I get no vendor.

628 114.574792  manufacturer_xx:xx:xx   1a:e1:3d:ca:4c:ac   ARP 42  Who has Tell
629 114.588296  1a:e1:3d:ca:4c:ac   manufacturer_xx:xx:xx   ARP 42 is at 1a:e1:3d:ca:4c:ac

The manufacturer_xx:xx:xx is my wifi adapter. is the default gateway ip and is the machine ip. The interesting fact is 1a:e1:3d:ca:4c:ac is not the mac of the default gateway. The unknown mac is communicating a lot with the network. I have a pcapng file of 29,206 packets. If I apply display filter, eth.dst == 1a:e1:3d:ca:4c:ac, I see around 40.1% packets went to the unknown mac.

asked 30 Aug '17, 03:39

mgtheboss's gravatar image

accept rate: 0%

That looks like a locally administered MAC, as the U/L bit is set (this is the second bit of the first octet, i.e. 1a -> 0001 1010). As such there is no manufacturer.

Wireshark should be informing you of the fact that the MAC list locally administered, what does it show in the packet tree? An example is show here.

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answered 30 Aug '17, 04:13

grahamb's gravatar image

grahamb ♦
accept rate: 22%

edited 30 Aug '17, 04:15

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question asked: 30 Aug '17, 03:39

question was seen: 1,343 times

last updated: 30 Aug '17, 04:15

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