The arp command can indeed do that so I won't call that proof. Did you try turning off the WiFi for a time? Remember that for best Netflix and streaming we don't deploy on WiFi but use Ethernet and powerline networking instead since it's so simple to interfere with WiFi.
Need some experienced feedback.
Recently I noticed some "quirks" with the quality of my network. Netflix signal would degrade or stop all together, frequent disconnects from streaming and gaming services on my PC. Called Comcast and they said nothing to worry about. I remained doubtful.
My networking knowledge is very limited but Im trying to learn more. so I mapped my network and then removed all wireless devices from it. Phones tablets etc The only thing left connected is my Ethernet connected PC. but when I run a "arp -a" from the commandline it shows 2 different internet addresses both with the same physical address. Both are dynamic. One of these is my PC, the other internet address shows Falls Church Virginia.
I have reset my modem, changed the name & password of my home network, changed the name of my ethernet connection and yet this internet address remains.
Is there any reason for this? Comcast said they only saw my ip address as the one connected to the internet. Why is this other dynamic address there? What could it reference? my modem? my router?
Any help or just a point in the right direction would be much appreciated.
Thanks.

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