.255 addresses still not usable after all these years?

David Andersen dga at cs.cmu.edu
Fri Jun 13 20:39:37 UTC 2008

On Jun 13, 2008, at 4:11 PM, Christopher Morrow wrote:

> On Fri, Jun 13, 2008 at 3:16 PM,  <Valdis.Kletnieks at vt.edu> wrote:
>> On Fri, 13 Jun 2008 15:08:47 EDT, David Hubbard said:
>>> I remember back in the day of old hardware and operating
>>> systems we'd intentionally avoid using .255 IP addresses
>>> for anything even when the netmask on our side would have
>>> made it fine, so I just thought I'd try it out for kicks
>>> today.  From two of four ISP's it worked fine, from Verizon
>>> FIOS and Road Runner commercial, it didn't.  So I guess
>>> that old problem still lingers?
>> RFC1519 is 15 years old now.  I *still* heard a trainer (in a Cisco
>> class no less) mention class A/B/C in the last few months.  Some evil
>> will obviously take generations to fully stamp out.
>> Anybody from Verizon FIOS or RoadRunner care to explain why David  
>> is seeing
>> an issue in 2008?
> not from either, and hopefully david will follow back up with some of
> his findings, but.. I'd bet dollars to donuts it's the ultra-crappy
> CPE both vendors ship :(
> go-go-actiontec (vol sends those out, god do they suck...)

Or leftover filters from before 'no ip directed-broadcast'
in the days of Smurf attacks.


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