Ricky Beam jfbeam at
Tue Dec 3 02:05:28 UTC 2013

On Mon, 02 Dec 2013 20:18:08 -0500, Owen DeLong <owen at> 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,  

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