Re: tlug: ip subnetting question..

[Jonathan Q <jq@example.com>]

On Fri, 3 Dec 1999, Scott M. Stone wrote:

> 
> OK, now I always thought that a netmask of 255.255.255.192 gave you 4
> subnets of 62 hosts each.  My CCNA book however *insists* that this mask
> gives you *two* subnets of 62 hosts each.
> 
> WTF??

I'm glad you asked that question, 'cuz I happen to have a Cisco Press
book sitting right here  :-)  Inside the front cover is a CIDR
conversion table, and the relevant line says:

/26  255.255.255.192  11111111 11111111 11111111 11000000 1/4C

This supports your belief.  Moreover, on P. 64 of this same book, it
states specifically that a /26 AKA 255.255.255.192 gives you 4 subnets,
bearing out the numbers of 11000000.

The book, if you want to pick it up yourself, is called Internet Routing
Architectures, by Bassam Halabi.  Published by Cisco Press, ISBN
1-56205-652-2.

You wouldn't think that a CCNA book would be wrong, but . . . 

Unless they are just referring to only two of the four, it seems as
though something is fishy there.

Anybody else got any ideas on this?

Jonathan

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