Question about subnetting /24's
I Am Not An Isp
patrick at ianai.net
Fri Mar 19 04:06:48 UTC 1999
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
I Am Not An Isp - www.ianai.net
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