Security blocking device

[Llondon]

How do I stop unrecognized devices connecting to my broadband

password is changed I can’t keep doing this every time I change password a new unrecognized devices attaches 

this is one 

34:5d:9e:ca:40:90

how are they connecting ? As account holder why can’t I approve what accesses my broadband and what doesn’t 

[Cynric]

@Llondon  If it hasn't been assigned an IP it hasn't joined the network. It could be a UPnP device. That address is from a Sagecom hardware. 

Possible devices could include phones, WiFi (neighbours), Sat-Nav, and watches.

[Cynric]

@Llondon  If you really want to block everything. Go to the router settings and stop it liberally handing out DHCP session. But you are going to spend a lot of time administering all the legitimate devices you want to connect.

[Ripshod]

Disable random mac on all your devices that use it by default (iphones, android phones, tablets, laptops etc) and use mac filters. Either that or stop looking.

Even when a device is connected to a stable network it'll still scan other networks for a better one. As long as it doesn't get an IP it's not actually connected.

Unless you have your WiFi running without a password.