Blocking users from Network? (Cisco EPC2425)

Ramza

Have a bit of a situation here and would like some assistance if possible

Long story short, I pay the broadband bill in my home and a certain family member (for reasons obviously I won't discuss!), said they would not like to be a part of the bill anymore (as we used to share the price), and in return would not use the home broadband anymore. So, I went ahead and changed the password on the router homepage (I use a Cisco EPC2425 from UPC), changed the wireless security key, and thus blocked them from internet access

This was fine for a few days, until I checked my network devices from my computer and also the connected devices on the access control panel from the router homepage, and seen that they were somehow using the internet. I got their mac address and put it into the mac address filtering and blocked access, but I am not sure this is enough! I have the MAC address and ip (static) of their computer, but I am still unaware if this is enough. My main three questions are as follows

1) The router/modem is situated in the guest room, where the phone line etc is, so it is the handiest place to put the router, and just so happens to be where said person stays! So it hit me that, maybe, this person is connecting through a wired connection using an Ethernet cable. My main question is, is there anyway I can know this? Will the persons IP/MAC address show up as a connected client if they are using wired connection? And, is there ANY way at all to stop this?

2)I am not too sure how to block out a connection or even if it has worked, I added their IP/MAC address to the MAC address filter and blocked, but under fixed CPE IP assignment, it still shows their computer as active...I am lost and would really like any advice on how I can block out said user wirelessly, and wired if possible!

Thank you for reading

Knasher

The router has an option for MAC filtering under the advanced settings section, add both the wired and wireless mac addresses in there. Should do the trick unless they figure out how to change their mac address.

Ramza

How do I find the mac address without access to their system? Will it show up while they are connected ?

colm_mcm

Surely there are other UPC points in the house other than in the guest room?

Knasher

I have that router but I don't use it as my DHCP server so I might be wrong on this, but there should be a section where you can see what ip address is handed out to what hostname and is should tell you the mac address on the same page. Failing that if you ping their computer when they are on the network you can view the arp tables and get it from there (just google arp and your os and it will tell you how).

Ramza

Thank you guys very much, I managed to get the Mac Address of said persons wireless and wired connections, no longer a problem Even if they do use a diff device to connect with a wire (as wireless has wpa-2 security on!), I will see the different mac address and just add it to the filter list :P

Thanks again, can close thread now