Re: Question about subnetting /24's

[I Am Not An Isp <patrick () ianai net>]

At 08:42 PM 3/18/99 -0500, Scott Gifford wrote:

> I have a /24 network I want to subnet into two /25's.  For realism's
> sake, let's call the network
>
>       216.40.155.0/24   (mask 255.255.255.0)
>
> So I have two 126-host networks, namely
>
>       216.40.155.0/25   (mask 255.255.255.128)
>       216.40.155.128/25 (mask 255.255.255.128)
>
> The person with whom I was calmly discussing the matter said that this
> configuration didn't make any sense, because my first subnet had all
> zeroes in the last octet, so it was an all-zeroes subnet; and the
> second had all ones on the last octet, so it was an all-ones subnet.
> And that these subnets were reserved as the network subnet, and the
> broadcast subnet, much as all-zeroes and all-ones in the host portion
> indicate the network and broadcast addresses.

He is correct for "classful" networking.  If you run classless IP, his
comments are irrelevant.


> Both myself and the customer are using Bay Networks routers.

Ahhhhhh.  I see your problem. :p


>  If anybody else is interested in this, let me know, and I'll
> summarize direct responses to the list.

I'm afraid that most people here know better.  But thanx anyway.

> ------Scott.

TTFN,
patrick

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