.255 addresses still not usable after all these years?

Mike Lewinski mike at rockynet.com
Fri Jun 13 22:26:57 UTC 2008

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 :)


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