identify hostname

Pete Kruckenberg pete at kruckenberg.com
Tue Dec 1 19:29:15 UTC 1998


On Tue, 1 Dec 1998, Alex P. Rudnev wrote:

> > > UUnet uses ascend TNT's which they claim you cant filter 
> > > directed-broadcast on. Ive ranted at them since October 20 to get this
> > > serious security hole closed.
> If they can't turn this off on ascend access server, they anyway can 
> filter out broadcast addresses in their border routers (CISCO's) 
> forwarding traffic to this access servers. The result is (almost) the 
> same.

Filtering broadcast addresses is pretty ugly. Consider that a single Class
C broken down into /30's can have 64 broadcast addresses. Maybe if it was
just filtering your own assigned subnets, it would be possible, but this
also applies to customer-subnetted broadcast addresses, so you'd have to
coordinate your filter with every one of your customers, every time they
change subnets. Not impossible, but pretty close.

Pete.





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