The use of .0/.255 addresses.

Sun Jun 27 02:03:49 UTC 2004

On Sun, Jun 27, 2004 at 12:32:40AM +0100, Jonathan McDowell wrote:
> 
> Have just spent some time trying to track down what seemed to be an
> elusive problem, I thought I'd mention it here.
> 
> I've had problems accessing www.level3.net, www.ebay.co.uk and
> www.dabs.com (and a few others I don't recall). As I'm the first user of
> a reasonably new netblock I thought it might be something to do with
> filters on our upstreams or similar. Trying an IP from our older
> netblock worked without problems, which seemed to back this up.
> 
> However eventually I tracked it down to the use of the .0 address from
> the new netblock; changing to use the .1 address meant I could access
> the above sites without any difficulty.
> 
> Various people I've asked about this have said they wouldn't use the .0
> or .255 addresses themselves, though couldn't present any concrete info
> about why not; my experience above would seem to suggest a reason not to
> use them.

This is what happens when your educational system continues to teach 
classful routing as anything other than a HISTORICAL FOOTNOTE 
*coughCiscocough*. This is also how you end up with 76k /24s in the global 
routing table.

Do you part to help control the ignorant population: whenever you hear 
someone say "class [ABC]" in reference to anything other than a historical 
allocation, smack them. Hard.

-- 
Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)