.255 addresses still not usable after all these years?

Jared nanog at namor.ca
Fri Jun 13 18:01:28 CDT 2008


Mike Lewinski wrote:
> David Hubbard wrote:
>> 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?
> 
> The TCP/IP stack in Windows XP is broken in this regard, possibly in 
> Vista as well, though I've yet to have the displeasure of finding out. I 
> have a router with a .255 loopback IP on it. My Windows XP hosts cannot 
> SSH to it. The specific error that Putty throws is "Network error: 
> Cannot assign requested address".
> 
> At least if I ever need to completely protect a device from access by 
> Windows users, I have a good option :)
> 
> Mike

We had to split our assigned ranges (PPP/PPPoE) into /24, even if it 
were assigned to the (NAS, BRAS, etc) in larger chunks.  It seems 
customers who were assigned the .0/.255 could get out there - but 
certain sites (IIS it seemed) would refuse to talk back.

I forget if I tested microsoft.com like this...




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