On Mon, 02 Dec 2013 20:18:08 -0500, Owen DeLong <owen@delong.com> wrote:
You don't, but it's easy enough for Windows to do discovery and/or negotiation for firewall holes with multicast and avoid making ...
Actually, your process still makes a very dangerous assumption... you have to assume the address passed via multicast is, in fact, a local address. Since it is necessarily outside your prefix, you have to either make assumptions about what is "close" to your prefix -- assumes the site is contiguous, or trust any address passed to you. Hackers will have fun screwing up your firewall rules and potentially breaking into your servers. (if you're foolish enough to not have any other layers in your network, which is likely with home networks.)
... They can't get away with flat out saying no...
Says who? TWC has been saying "no" for years. (unless I'm mistaken, "always".)