Using x.x.x.0 and x.x.x.255 host addresses in supernets.

Wayne E. Bouchard web at typo.org
Tue Jan 8 20:24:10 UTC 2008


Historically, .0 and .255 have been avoided because a lot of servers
(windows) wouldn't work using that as a host address or would flag it
as invalid if you tried to connect to it or a myriad of other
problems. Note that this was a limitation of the host, not anything to
do with the network or any of the network equipment.

This issue has not existed with any prevelance for quite some time and
almost everything of recent manufacture is quite happy to be assigned
in a supernet as well as on the .0 and .255 addresses.

So my oppinion is don't hesistate to use it until you find a real,
reproducible problem.

-Wayne

On Tue, Jan 08, 2008 at 05:45:36AM -0800, Joshman at joshman dot com wrote:
> Hello all,
>   As a general rule, is it best practice to assign x.x.x.0 and x.x.x.255 as host addresses on /23 and larger?  I realize that technically they are valid addresses, but does anyone assign a node or server which is a member of a /22 with a x.x.x.0 and x.x.x.255?  Is it just a manner of preference on whether or not to use them, or are there functional reasons you shouldn't; either with rfc 1918 addresses or public addresses.
>   Thanks in advance,
> J
> 
>        
> ---------------------------------
> Never miss a thing.   Make Yahoo your homepage.
---
Wayne Bouchard
web at typo.org
Network Dude
http://www.typo.org/~web/



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