How Do IP Addresses Work?

learninmypc

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Every device connected to a network—computer, tablet, camera, whatever—needs a unique identifier so that other devices know how to reach it. In the world of TCP/IP networking, that identifier is the Internet Protocol (IP) address. FULL ARTICLE
 
To continue on the subject of IP address ...

IP addresses are grouped into two sets; Routable and non-routable.

  • Routable addresses are all public and unique, whether IPv4 or IPv6
  • Non-routable addresses are all private and used to create local Lans, and there are thousands of duplicates, like 192.168.1.1
So if there are so many duplicate addresses on our LANs, how does this possible work?

This is the subject of NAT: Network Address Translation explained here.
 
Private addresses are not non-routeable. I use them for OSPF management connections in a fully routed network. They are just not routable to the public without NAT.
 
Private addresses are not non-routeable. I use them for OSPF management connections in a fully routed network. They are just not routable to the public without NAT.
That's what the context of non-routable means - - ie: can't be used or accessed by a public network.
 
On another side note of this though I have never been able to route the true non-routable address space of 169.254.0.0/16. I have tried it on many platforms. However I have been able to access it across a split LAN segment on seperate L2 subnets and vlans if multiple NICs are used on a single device.
 
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