Technically it fits inside the highest class-A subnet… but I’ve seen so many people (especially teachers) who think that class-A and /8 subnets are equivalent that I firmly believe that the idea of classful networking should be removed from technical literature altogether.
Classful IPv4 was obsoleted 32 years ago. Only 8 years left before it’s literally older than a standard career.
It’s fascinating the sheer inertia that leads formally-trained IT professionals to use and perpetuate such profoundly useless and obsolete nomenclature. You’d think that having an incorrect use of the term “class A” and not having any use for classes B and C would tip off academia that they should cordon off classful networking to the “History of Computing” course next to ARPANET.
Maybe next time someone refers to 10.0.0.0/8 as a Class A network I’ll refer to it as the ARPANET Network. That’s only very slightly more anachronistic (3 years).
Yes. 127.0.0.0/8 is reserved IPv4 address space for Loopback. It is perfectly valid, and occasionally useful, to use other loopback addresses that are functionally identical, like 127.0.1.1 or 127.0.0.53, which carry semantic information for the initiated, like “53? Must be DNS-related, obviously!”
Wait. Is that last one really home?
It’s a Class A address, reserved for loopback devices. While not any sort of default - yes, it could be used as home :)
Keep in mind the modern ipv4 internet uses classless subnets so it is better to think of it as a /8
Technically it fits inside the highest class-A subnet… but I’ve seen so many people (especially teachers) who think that class-A and
/8subnets are equivalent that I firmly believe that the idea of classful networking should be removed from technical literature altogether.Classful IPv4 was obsoleted 32 years ago. Only 8 years left before it’s literally older than a standard career.
It’s fascinating the sheer inertia that leads formally-trained IT professionals to use and perpetuate such profoundly useless and obsolete nomenclature. You’d think that having an incorrect use of the term “class A” and not having any use for classes B and C would tip off academia that they should cordon off classful networking to the “History of Computing” course next to ARPANET.
Maybe next time someone refers to
10.0.0.0/8as a Class A network I’ll refer to it as the ARPANET Network. That’s only very slightly more anachronistic (3 years).Yes. 127.0.0.0/8 is reserved IPv4 address space for Loopback. It is perfectly valid, and occasionally useful, to use other loopback addresses that are functionally identical, like 127.0.1.1 or 127.0.0.53, which carry semantic information for the initiated, like “53? Must be DNS-related, obviously!”
At the place I work, we use 10.127.0.0/16 for loopback addresses on networking equipment because it has that little familiarity from 127.0.0.0/8
Only with a /8 or 255.0.0.0 netmask. Which is not very common.