Why does CFv3 continously find new networks?

I’m on a wired broadband connection, and every week or so Comodo pops up saying that it’s found a new private network, but I don’t have any other PC’s in my house. I only have one computer wired to Cable. Is it safe to allow these networks, or should I deny them? What are the risks of accepting the discovery? I’m on Vista Home Premium 32-Bit. Thank you for the help (R)

Do the networks look like 169.254.xx.xx? If so, they are just indications of a temporary problem with the DHCP server that provides your IP address.

Off the top of my head I can’t remember exactly what the numbers we’re but I’m 90% sure it used that same range. Are the problems with the DHCP server mine? Or something on my ISP’s end? Thanks