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From: rjberke@skvax1.csc.ti.com (Richard Berke - TI Data Communications)
Newsgroups: comp.protocols.tcp-ip.ibmpc
Subject: (none)
Message-ID: <9103211443.AA25492@tilde>
Date: 21 Mar 91 14:43:56 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
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From:	SKVAX1::RJBERKE      "Richard Berke - TI Data Communications" 21-MAR-1991 08:25:05.32
To:	TILDE::"pcip@udel.edu"
CC:	RJBERKE
Subj:	Tutorial on netmasks wanted

I get confused about values possible for netmasks. 
I'm looking for either advice from the readers here, or
references to publications which cover the material.

I'm okay on the concept that for a class B network, the value in the
third octet COULD be used as part of the identification of the network
portion of the address, and I've used 255.255.255.0 as a netmask successfully.
I think I understand the idea of a mask matching all or no bits.

How do you go about figuring out the right mask to set for some other 
subset of values for the octet?  I've seen references here on PCIP about
other values, but I'm missing the understanding of how to determine the mask
for ranges of values.

Can a reader explain to me with examples? other references?

Thanks,
Richard Berke
Texas Instruments
rjberke@skvax1.csc.ti.com