I have device on my network that stupidly sends out ARP broadcasts every second asking who has its own IP address (below is a record from a Wireshark capture):
32:bd:9f Broadcast ARP Who has 192.168.0.21? Tell 0.0.0.0
This is not related to DHCP (I have that off and the device has a static IP). Nor does any other device on the network have the same IP.
Why is this a problem? It is completely destroying the battery life of every mobile device connected to the WiFi network. Looking at my Android phone, 98% of the battery drain is attributed to WiFi RX Wakelocks and it has 0 seconds in "Deep Sleep". In other words, the phone cannot enter a low power state because it is having stay awake to handle these ARP broadcasts. It runs out of battery from a full charge in about 2 to 3 hours. The same thing happens to the rest of the household's tablets and mobile phones.
To put this in perspective, if I disconnect this misbehaving device from the network, the battery life of my phone is still at 70%-80% after 16 hours and it report that it has been in a deep sleep for about 15 hours of that time. Other devices have similar battery life improvements.
I've reported the bug to the vendor but I'm not holding out much hope.
I know that if I have a 2nd router, I can segment the network because routers don't normally forward broadcasts to other segments - but this requires me to buy an additional router.
I could also run the WiFi in "Isolation" mode so that all the WiFi devices can only access the internet and not the LAN (hence they don't get LAN broadcasts). Unfortunately I need to access my LAN from the WLAN (for printers and remote desktop etc).
So, I'm wondering if there's anything I can do from the RT-N66U side. The offending device is plugged directly into a specific port RT-N66U and I'm kinda wondering if anybody has any cool ideas how I can tell the RT-N66U not to forward ARP broadcasts received via that port.
32:bd:9f Broadcast ARP Who has 192.168.0.21? Tell 0.0.0.0
This is not related to DHCP (I have that off and the device has a static IP). Nor does any other device on the network have the same IP.
Why is this a problem? It is completely destroying the battery life of every mobile device connected to the WiFi network. Looking at my Android phone, 98% of the battery drain is attributed to WiFi RX Wakelocks and it has 0 seconds in "Deep Sleep". In other words, the phone cannot enter a low power state because it is having stay awake to handle these ARP broadcasts. It runs out of battery from a full charge in about 2 to 3 hours. The same thing happens to the rest of the household's tablets and mobile phones.
To put this in perspective, if I disconnect this misbehaving device from the network, the battery life of my phone is still at 70%-80% after 16 hours and it report that it has been in a deep sleep for about 15 hours of that time. Other devices have similar battery life improvements.
I've reported the bug to the vendor but I'm not holding out much hope.
I know that if I have a 2nd router, I can segment the network because routers don't normally forward broadcasts to other segments - but this requires me to buy an additional router.
I could also run the WiFi in "Isolation" mode so that all the WiFi devices can only access the internet and not the LAN (hence they don't get LAN broadcasts). Unfortunately I need to access my LAN from the WLAN (for printers and remote desktop etc).
So, I'm wondering if there's anything I can do from the RT-N66U side. The offending device is plugged directly into a specific port RT-N66U and I'm kinda wondering if anybody has any cool ideas how I can tell the RT-N66U not to forward ARP broadcasts received via that port.