What happens to ip addresses if there are over 4,23 billion internet users.

IPv6

This is planned for. I wouldn’t worry about it.

You also have to remember that those 4,23 billion internet users can have conflicting IP’s because they’re not all acting as servers and dishing data based on their IP, it’s local conflict you have to worry about.

Surely each internet-enabled device must have an individual IP address otherwise the data may get sent to the wrong thing, right? Unless it works on an entirely different network (i.e. not using any global DNS servers using a pure internally developed system).

Sky is right. IP’s cannot conflict no matter if a server or client.

It would be like having two houses next door to each other with the exact same street/mailing address.

@jp is right… IPv6 will handle that situation when it comes to unique machines connected directly to the Internet.

Most computing devices are not connected directly though. They connect to a subnet instead.

So, IBM for example, might have a single IP address for its proxy gateway on the Internet. Behind that proxy could be literally millions more devices with unique IP addresses within that subnet. (IBM actually has a rather large block, but my example is still valid).

Those subnet IP addresses might employ duplicate numbers as what’s on the Internet itself, but that doesn’t matter as the subnet mask is part of the mechanism to keep things separate.

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For example, suppose a home network consists of computers named Foo and Bar, connected to a router, and then via a cable modem to the Internet. The home network is configured as a subnet. Address 17.76.99.1 is assigned to Foo, and 17.76.99.2 to Bar. The subnet has been configured so that the first three octets of its members’ addresses are all the same subnet id, 17.76.99, and this fact is expressed by the subnet mask 255.255.255.0 (binary 11111111 11111111 11111111 00000000) configured in the router. When Foo sends data to http://amazon.com at 72.21.210.11, the router performs a logical AND of the address with the subnet mask, recognizes that the first three octets of the address are not within its subnet, and therefore sends the data over the Internet, via the subnet’s default gateway. When Foo sends data to Bar, however, it determines that the destination lies within the subnet and the default gateway is not required. The data is transmitted directly from Foo to Bar within the home network.

Oh, and by the way… the IP v4 address space is actually a 32-bit number, and the individual octets may have a value ranging from 0 to 255… which is 256 unique values.

256^4 == 4,294,967,296 == 2^32 (which is why it’s called “32-bit”)

Your original estimate was close enough for government work. ;-)

IPv6 will use a 128-bit number system == 2^128 or roughly 3.4×10^38 addresses. To put that in perspective, that would allow for each of the 6.5 billion people alive today to each have 5×10^28 unique computer addresses connected to the Internet.

I expect IPv6 will run out of address space after a while, though.

Version 6 of IP is already implemented at certain areas. It is said that it can accomodate 4 million computers per square meter area on earth. So dont worry about that

An analysis on general technical things

In response to robmandu.

So IPv5 was 64 bit? lol

(LOL @ the pigs fly)