IP address conflict

I have a wireless network configured with 2 Wireless routers set up with DHCP - non-conflicting ranges and 6 computers set up with fixed IP . I have not set any encryption as I want casual users to be able to logon in our cafe and use our Internet. Recently I am getting an ip conflict popup on one of the pcs which I can only imagine is caused by a neighbour's warless LAN . Is there anything I can do about this ?

Reply to
-keevill-
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"-keevill-" hath wroth:

If the two networks have different SSID's, then there won't be any cross pollenation.

With no encryption, there's nothing to prevent someone from connecting using their own invented static IP address. That's probably where your IP address conflict is coming from. My guess(tm) is someone sniffed the traffic, extracted your IP address layout, and decided to "borrow" one of your client's IP addresses.

Do your static IP's land in the middle of either DHCP range? If so, you may eventually have an address conflict. I know you said "non-conflicting" but I can't tell exactly what is non-conflicting. The 6 computers with fixed IP's or the DHCP ranges?

Reply to
Jeff Liebermann

They have different SSIDS , I can see the name of his network on our machines when we scan network for wireless routers.

Yes that's what I am guessing too. Is there anyway to prevent that ? Perhaps block an ip range on our network ??

The wired machines have fixed ip in the range 192.168.0.1-10 The 1st router has DCHP range of 192.168.0.50-80 The 2nd router has DCHP range of 192.168.0.100-120

Thanks !!

Reply to
-keevill-

"-keevill-" hath wroth:

Well, that mostly eliminates your neighbor as a possible culprit. His wireless computah might have been setup to connect to literally ANY wireless access point, which I guess would include yours. However, that's not the default and rather uncommon.

Nope. He'll just find another IP address to borrow.

I have a similar "open" setup. I use a MAC address filter for the wireless connections. It's very easy to bypass, but it does serve the purpose of preventing accidental connections. I have a neighbor that just can't stay off the porno sites. He has his own wireless router and DSL, but he turns it off a night. Meanwhile, the laptop wanders over to my system and spews viruses and worms. So, I made a list of the acceptable MAC addresses, applied the NAC filter, and he was history. He could easily change his MAC address, but I have a trick that will easily detect his laptop. The SSID is my address, so if anyone wants to use the system, they can bang on the door or call me. I've added about 10 such transient laptops for various neighbors.

Perfect. The IP conflict is not coming from one of your machines. Unfortunately, that probably means a hacker or someone looking for some free bandwidth. Such is the joy of running an open and unencrypted wireless system. Good luck.

Reply to
Jeff Liebermann

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