Huge number of ARP broadcasts normal on cable networks?

[Kilrah]

Since a few weeks my router crashes/reboots anywhere between once every couple of days to multiple times in the same day. I've reset and reconfigured it with no change, and have gone to connect my PC straight to the modem to see if I could see something iffy.

The ISP's gateway seems to flood the network with about 100 ARP broadcast packets per second, and causes a dozen of responses to those per second.

 

Does anyone with some cable experience know if this is typical, or if it is worth me trying to go through the inevitable support maze with the ISP until I get to someone who has an idea and agrees there might be something wrong on their end/has a look?

[flashiling]

are there more than one DHCP server in your network?

[Kilrah]

Nope. And at the time of analysis there is none since I completely disconnected my own network and connected the PC straight to the modem.

 

I've done more searching and found that "it's normal to see many ARP requests" on a cable network, but no indication of how many "many" is... i.e. still no idea whether 100+ per second counts as normal...

[Windows7ge]

I can't tell you if 100's of ARP requests a second are normal (but I'm betting no - sounds unnecessary for the router to populate it's table that many times in such a short span) but the resetting/crashing you've mentioned is very much not normal at all. If it's crashing/rebooting up-to multiple times a day I wouldn't worry about seeing what it's broadcasting I'd get it replaced.

 

And maybe its time to buy your own Modem+Router so you don't have to get your ISP as involved in the future.

[Kilrah]

The router is mine, and yes if this is normal it's going to be replaced, just one more router that won't have lasted more than 3 years... but I don't want to replace it if it's crashing because it's getting spammed out of the ordinary.

 

The modem I have no choice, can't use anything other than the ISP-supplied one. But it's working fine.