Trying to throttle my neighbor on my network

pvsmith2

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Sep 22, 2008
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18,510
hey guys, so i share my wireless with my downstairs neighbor. however recently she has been doing something, not sure what, that is sucking the hell our of the bandwidth. she is a really nice lady and i dont want to cut her off completely so i was trying to find a way of throttling her devices.
1. i recently loaded dd-wrt onto my linksys wrt400n, and have been trying to get Qos to work so that i can set a priority for my roommate and my computers.
2. i have a basic idea on how to set it up, but i need the MAC address of the downstairs neighbor.
3. i tried pinging the ip address, but i get "reply from 192.168.1.121: destination host unreachable"
4. when i use the command "arp -a" the mac address isnt listed.
5. whats also strange is the above address is not the one i am pinging. i am trying to find 192.168.1.127.
6. im treading in new waters here with networking, just learning as i go so i might be missing something obvious.

thanks guys!