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class A private IP range (10.0.0.0 to 10.255.255.255) class A public IP range (1.0.0.0 to 127.0.0.0)

In these 2 public and private IP ranges, the private IP range is also included into the public range, right? because 10.x.x.x is in between the public IP range (1.0.0.0 to 127.0.0.0). Why is that?

In this case, isn't it a problem that including one IP into both private and public ranges.

Please don't mention about the IP classes here because that is not what I am asking. I just need to know why same IPs are used in both public and private ranges.

Any clarification would be really appretiated.

Sahan
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  • Network address classes are dead (please let them rest in peace), killed in 1993 (two years before the commercial Internet in 1993) by RFCs 1517, 1518, and 1519, which defined CIDR (Classless Inter-Domain Routing). We have not had network address classes in this century. The last two sections of this two-part answer explain about private addressing and the obsolete network address classes. – Ron Maupin Jan 17 '23 at 04:22
  • If you must go back internet-centuries, to a time long before you were born (probably), yes, the three blocks defined in RFC1918 ("Private" addresses), are each Class A (/8), Class B (/16), and Class C (/24) subnets. 10/8 is the only one from the Class A block, because (a) who needs more space, and (b) address space is finite. These subnets are "private" only because RFC1918 designates them as not globally routable. They are otherwise routable, following the same rules as any other unicast range. – Ricky Jan 17 '23 at 08:27
  • I think i asked the question incorrectly. I am going to edit my question – Sahan Jan 17 '23 at 09:44
  • @Sahan Network classes worked by looking at the four leading/most significant bits of an IP address. Private addresses (RFC 1918) were just block allocations and an arbitrary choice, possibly just what the next free blocks where. – Zac67 Jan 17 '23 at 13:22
  • The quote you provided is inaccurate and confusing. – Ron Trunk Jan 17 '23 at 13:31
  • @Zac67 I am going to read that RFC. Thank you. – Sahan Jan 17 '23 at 17:25

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Classful networking/subnetting is no longer relevant in real world use. Class based subnetting (Class A, B, C, etc.) have no meaning in actual network deployments and are interesting only as historical reference and as naming reference. People still say 'Class C' when they mean /24. For more information see CIDR and Classless networking.

https://www.geeksforgeeks.org/classful-vs-classless-addressing/

FrameHowitzer
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