Hi anyone,

I have been reading for two days everything I can find about IP addresses, including the tutorials on this forum, Wikipedia, Whatis, how stuff works. I understand dotted quads. I understand that every device on a network needs and unique address. I understand that 4 binary octets totals 4+ billion numbers.

I have also read that the URL in a browser window is translated to an IP address. What does this have to do with a device on the internet. Every webpage on every website in the world would need a unique IP address. Add all the computers (and other devices) and there have to be more than 4 billion. There are probably a billion websites alone, If each had four pages--see what I mean.

I am just looking for some clarification.

Thanks to anyone who can enlighten me.

Charles

Not every page on a website will have it's own IP, for example this thread will use the geekstogo.com IP, not it's own IP.

For the network thing - each device connected to the network will get it's own unique IP address that is only local and it uses a reserved range so that there won't be an IP conflict. The WAN IP address used in the internet will be given to the network.

It's a bit complicated to explain in technical terms, so I'll just give you a scenario - imagine that four people live in an apartment. The people in this scenario are the computers, and the apartment building is the network. They all have their own rooms numbered one to four. The room numbers are the local IP address. The apartment will have an address that it uses for the world. That address is the WAN IP address.

It's a bit complicated, so ask any question that pops into your mind.

Yes, you are right; and that's why they introduced IPv6. This protocol was intended to take over for IPv4, however it hasn't really kicked off yet. IPv6 allows something like 340,282,366,920,938,000,000,000,000,000,000,000,000 unique IP Addresses, which is more than enough.

However, the reason why IPv6 hasn't really 'gone big' yet is because of what QuizMaster was referring to; Network Address Translation. This pretty much took care of the limited number of IP's for the time being, although IPv6 will slowly begin to take over. If you want to learn more on the subject, our very own dsenette wrote an excellent article on it here -- Basics of NAT, (Network Address Translation). It's a good read and well worth it

Thanks,

I read the NAT article (will have to reread 5 to 10 more times). That clears things up a bit. Here are the articles that confused me

http://www.boutell.com/newfaq/misc/sizeofweb.html

and this

http://en.wikipedia.org/wiki/Domain_Name_System

It just seemed that with all the websites AND devices on the web from all over the world, 4 billion ip addresses would already be used up.

Will continue reading and hopefully learning.

Thanks again.

Charles

I think have found what I was looking for.

I had trouble understanding how a router could divide one public ip into multiple private ip adresses for individual computers on a lan. Ports is the answer to my question. NAT assigns a unique port number to each computer and keeps track of this in its assignment table.

Theoretically the total number of IP addresses possible is the original 4 billion times the number of ports per device, about 65,000. 4 billion times 65,000. I know the number is smaller because of assignments.

Am I correct in my thinking?

Good man

I can't say I've done the math, but your basic theory is right on the mark.

Good job.
- Dan

IPv4 uses 32-bit (4-byte) addresses, which limits the ip address space to 4,294,967,296 (232) possible unique addresses. However, IPv4 reserves some addresses for special purposes such as private networks (~18 million addresses) or multicast addresses (~270 million addresses). This reduces the number of addresses that can be allocated as public Internet addresses, and as the number of addresses available is consumed, an IPv4 address shortage appears to be inevitable in the long run. This limitation has helped stimulate the push towards IPv6, which is currently in the early stages of deployment and is currently the only offering to replace IPv4.

IPv4 addresses are usually represented in dot-decimal notation (four numbers, each ranging from 0 to 255, separated by dots, e.g. 208.77.188.166). Each part represents 8 bits of the ip address, and is therefore called an octet. In less common cases of technical writing, IPv4 addresses may be presented in hexadecimal, octal, or binary representations. When converting, each octet is usually treated as a separate number.