@Dashrender said in Subnetting help:
@scottalanmiller said in Subnetting help:
s this, but they didn't pay attention to their own example. Because they use the old, silly notation it is less obvious how they
They, the authors, are probably assuming old school classes for the network on 192.168.123.0 of /24... which is horrible writing, and lack of explanation.. but possible.
Right, and if they are, it means they don't know the most basic pieces of IPv4. Classful subnets were replaced in 1993. And even pre-1993, it was still less solid than would make what was presented by the author here accurate.
Given that it has been 27 years, there is really no excuse for the oldest, most out of touch networking person to think in classful terms. For 95% of the industry, classful networking hasn't existed during their careers. For 50% of the industry, it hasn't existed in their lifespans. In "IT generational" terms, it's been like five or more generations of IT pros since classful existed, so the "mentors teaching interns" problem has had five or six generations for people to catch on.
This means that the authors not only aren't doing a good job explaining, but lack the skills required for the A+ and certainly aren't prepared to sit for the Net+. This is the first stuff you have to learn about IP networking, because without it, you can't determine how to document or know what the network addresses of your network are!
