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Filtering source IP addresses

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Anonymous (not verified)
Filtering source IP addresses
Hi, I have problem with few "zombie" hosts in my network. When I use show cable host at my CMTS, in listed addresses is my gateway address. Is there any possibility to filter this at cable modem? Example query: C3#show cable host 172.21.73.240 MAC Address IP Address Type 0008.a1af.6253 172.21.73.249 learned 0008.a1af.6253 77.71.18.34 learned 0008.a1af.6253 77.71.45.82 learned 0008.a1af.6253 192.168.1.1 learned <--- gateway 0008.a1af.6253 85.224.128.170 learned 0008.a1af.6253 91.76.15.137 learned 0008.a1af.6253 91.78.7.209 learned 0008.a1af.6253 77.71.9.141 learned 0008.a1af.6253 70.241.106.4 learned 0008.a1af.6253 77.71.20.48 learned 0008.a1af.6253 75.5.181.134 learned 0008.a1af.6253 86.105.95.253 learned 0008.a1af.6253 91.201.172.153 learned 0008.a1af.6253 24.22.244.4 learned 0008.a1af.6253 88.104.19.104 learned 0008.a1af.6253 24.16.250.184 learned 0008.a1af.6253 121.6.67.186 learned 0008.a1af.6253 140.112.27.110 learned 0008.a1af.6253 124.169.64.242 learned
cmcaldas
"zombie" hosts

Thinking you have a bridge cmts... good thing is it passes everythings... appletalk, dhcp from everybody that connected a router up backwards, and so on. your best bet is to stop it at it's source by blocking source address and ports.
btw, why would you make your gateway the same as most of the routers sold on the market?
have you tried to apply access lists to your cable interface?