Happy #CIDRDay, everyone!

Today in 1993, Class A, B, and C addresses were deprecated in favor of classless addresses.

28 years ago.

If a computer person talks about Class C addresses, they are not competent

https://mwl.io/archives/3758

Happy #CIDRDay! – Michael W Lucas

@mwlucas I am not incompetent, I am old.

Old habits and such.

@sblaydes I am also old. We gotta learn.

Especially when speaking to the next generation.

@mwlucas So what is the proper term for any network that is a /24?

Learned Class C as interchangeable with /24.

@sblaydes it's a /24, pronounced "slash 24."
@mwlucas
Thank you. I tend to think in slashes, but have one friend who still thinks in classes. After working with him a bit, I tend to abuse the Class C term.

@sblaydes between you and me, I get it. But the kids are listening.

It's like telling a eavesdropping child "don't swear, dammit."

@mwlucas @sblaydes @phessler Hassling me about it helped me break the habit.

@sng @mwlucas @phessler

Oldster shakes his fist at the sky yelling "Get off my Class C".

@sblaydes @sng @mwlucas classfull networking has additional meanings than pure network size. It also mandates which ranges it is in, and how routing works.

Unless you were assigned an actual Class C in the 1980s, you never had one. And even if you were assigned an actual Class C, you no longer have one because they ceased to exist in 1993.

@sblaydes @mwlucas It's funny because /24 and class C aren't identical. C is specifically a /24 network in the range of 192.0.0 through 223.255.255

So you could just start being pedantic about it. That may cure some folks. 

(I thought they were the same for many years)