North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: SMURF AMPLIFIER BLOCK LIST -- VERY LARGE!!!!!!!!!!!!!!!
Phillip Vandry <[email protected]> writes: [...] > Every router on there has had directed broadcasts disabled for a long time. > Only that network is a /25, so the broadcast address we are talking about > is 205.236.182.127. > > It turns out that not only does 205.236.182.255 unexpectedly function as > an alternate broadcast address for this network, but it is unaffected by > no ip directed-broadcast!!! We've seen this type of behavior as well, and on larger networks than /24's. On one /18 that we have, someone was sending to xx.xx.255.255, and it was heading to the first /23 that was allocated out of that block. The customer that was lucky enough to be the recipient eventually had to explicitly deny the 255.255 address because no ip directed-broadcast didn't stop it. -- Matt Ranney - [email protected] Let's not let the students run the High School.
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